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15150-Smith College Stormwater Report_20231101 November 1, 2023 Stormwater Report Smith College Lazarus-Wurtele Center College Lane Northampton MA 01063 Prepared for: TenBerke Architects D.P.C. 41 Madison Avenue, 17th Floor New York NY 01001 Prepared by: Nitsch Engineering 2 Center Plaza, Suite 430 Boston, MA 02108 Nitsch Project #15150 Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 i TABLE OF CONTENTS SECTION 1 Introduction ........................................................................................................................................................ 1 SECTION 2 Existing Conditions .............................................................................................................................................. 2 Existing Drainage Infrastructure ...................................................................................................................................................... 2 Natural Resources Conservation Services (NRCS) Soil Designations ................................................................................................ 2 Onsite Soil Investigations ................................................................................................................................................................. 2 Wetland Resource Areas .................................................................................................................................................................. 2 Total Maximum Daily Load (TMDL) ................................................................................................................................................. 2 SECTION 3 Proposed Conditions ........................................................................................................................................... 3 Project Description ........................................................................................................................................................................... 3 Stormwater Management System ................................................................................................................................................... 3 Stormwater Management During Construction .............................................................................................................................. 4 SECTION 4 Stormwater Management Analysis ..................................................................................................................... 5 Methodology .................................................................................................................................................................................... 5 HydroCAD Version 10.10 .................................................................................................................................................................. 5 Existing Hydrologic Conditions ......................................................................................................................................................... 6 Proposed Hydrologic Conditions ...................................................................................................................................................... 6 Peak Flow Rates ............................................................................................................................................................................... 6 SECTION 5 City of Northampton Stormwater Regulations .................................................................................................... 7 LID Design Strategies ....................................................................................................................................................................... 7 Annual Load Reduction of Phosphorus (50%) and TSS (80%) ........................................................................................................... 7 Annual Load Reduction of Nitrogen ................................................................................................................................................. 7 SECTION 6 MassDEP Stormwater Management Standards ................................................................................................... 8 Standard 1: No New Untreated Discharges ..................................................................................................................................... 8 Standard 2: Peak Rate Attenuation ................................................................................................................................................. 8 Standard 3: Groundwater Recharge ................................................................................................................................................ 8 Standard 4: Water Quality Treatment ............................................................................................................................................. 8 Standard 5: Land Uses with Higher Potential Pollutant Loads ......................................................................................................... 9 Standard 6: Critical Areas ................................................................................................................................................................ 9 Standard 7: Redevelopments ........................................................................................................................................................... 9 Standard 8: Construction Period Pollution Prevention and Sedimentation Control ......................................................................... 9 Standard 9: Operation and Maintenance Plan ................................................................................................................................ 9 Standard 10: Prohibition of Illicit Discharges ................................................................................................................................. 10 ii SECTION 7 Closed Drainage System Design ........................................................................................................................ 10 SECTION 8 Conclusion ........................................................................................................................................................ 10 FIGURES ..................................................................................................................................................................................... 11 DR-1 Existing Watershed Areas ..................................................................................................................................................... 11 DR-2 Proposed Watershed Areas ................................................................................................................................................... 11 Figure 1 - USGS Aerial Map ............................................................................................................................................................ 11 Figure 2 - USGS Locus Map ............................................................................................................................................................ 11 Figure 3 - NHESP Map .................................................................................................................................................................... 11 Figure 4 - Wetlands Map ............................................................................................................................................................... 11 Figure 5 - FEMA Flood Map ............................................................................................................................................................ 11 APPENDIX A ............................................................................................................................................................................... 12 Stormwater Management Standards Documentation .................................................................................................................. 12 APPENDIX B ............................................................................................................................................................................... 13 Existing Conditions – HydroCAD Calculations ................................................................................................................................ 13 APPENDIX C ............................................................................................................................................................................... 14 Proposed Conditions – HydroCAD Calculations .............................................................................................................................. 14 APPENDIX D ............................................................................................................................................................................... 15 Closed Drainage System Design ..................................................................................................................................................... 15 APPENDIX E ............................................................................................................................................................................... 16 Long-Term Pollution Prevention and Stormwater Operation and Maintenance Plan ................................................................... 16 APPENDIX F ............................................................................................................................................................................... 17 Draft Stormwater Pollution Prevention Plan (SWPPP) ................................................................................................................... 17 APPENDIX G ............................................................................................................................................................................... 18 Soil Investigations .......................................................................................................................................................................... 18 APPENDIX H ............................................................................................................................................................................... 19 Phosphorus, Nitrogen, and TSS Removal Calculations ................................................................................................................... 19 Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 1 SECTION 1 Introduction Nitsch Engineering has prepared this Stormwater Report to support the Site Plan Review and Notice of Intent application to the City of Northampton for the new Smith College Lazarus-Wurtele Center located in Northampton, MA. The Project site is located at 8 College Lane in the Smith College Campus (subsequently referred to as the “Site”). The site improvements include the following: 1. Demolition of the existing 8 College Lane building; 2. Construction of a new Lazarus-Wurtele Center building; 3. Construction of pedestrian walkways and outdoor space; 4. Installation of new utilities to support the proposed building; and 5. Construction of a new stormwater management system. The proposed stormwater management system has been designed to comply with the requirements of the City of Northampton Rules and Regulations and the Massachusetts Department of Environmental Protection (DEP) Stormwater Management Standards. 2 SECTION 2 Existing Conditions The Site is located at 8 College Lane in Northampton, MA. The site is bound by Chapin Way to the northeast, College Lane to the west, and the Lyman Plant House and Conservatory to the south. The existing site contains the existing 8 College Lane building, a parking lot, and supporting site walkways. Existing Drainage Infrastructure Stormwater generated by the existing site is collected using a series of interconnected catch basins and is piped via a closed drainage system to a 12” drainage main in College Lane. The existing stormwater management system was constructed prior to the 2008 MassDEP Stormwater Management Standards, and the Site provides minimal peak flow attenuation, water quality treatment, and groundwater recharge. Natural Resources Conservation Services (NRCS) Soil Designations There is no data available for the site on the NRCS website. Please refer to the Onsite Soil Sections below for more information. Onsite Soil Investigations Haley and Aldrich performed 6 borings from May 15, 2023 to June 9, 2023. These borings were located around the proposed building and in the existing parking lot footprint. Results of these borings indicate soils with poor infiltrating capacity due to the presence of silt and clay layers. Additionally, borings indicate a perched groundwater table. Haley and Aldrich recommended the design groundwater level to be located at elevation 183. These boring logs are provided in Appendix G. Wetland Resource Areas The site is in proximity to Paradise Pond, which is part of the Mill River. Paradise Pond is located to the southwest of the site and has a 200-foot jurisdictional Riverfront Area under the Massachusetts Wetlands Protection Act. Refer to the Wetlands Delineation Report (Attachment C in the NOI) for more information. Total Maximum Daily Load (TMDL) The Site ultimately discharges into Paradise Pond, which is part of the Mill River. This portion of the Mill River is classified as a Category 5 water by the Massachusetts Integrated List of Waters, with an impairment of E. Coli. The Site is located within the Connecticut River Basin Watershed and will potentially be subject to a Draft Pathogen Total Maximum Daily Load (TMDL) if it is finalized by MassDEP. The Project has been designed to minimize stormwater discharge and associated pathogen pollutants through extensive filtration practices to meet the intent of the TMDL. Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 3 SECTION 3 Proposed Conditions Project Description The proposed Project includes the construction of the new Lazarus-Wurtele Center and the supporting site. The proposed site improvements include the following: 1. Demolition of the existing building; 2. Construction of a new building; 3. Construction of new accessible and pedestrian walkways; 4. Installation of new utilities to support the proposed building; and 5. Construction of a new stormwater management system. The Project is considered a redevelopment and is anticipated to decrease the overall impervious area for the Site by 851 square feet (0.02 acres). There is approximately 860 square feet of permeable pavers and 1000 square feet of green roof area provided in the proposed design. Refer to Table 1 for a comparison of the existing and proposed land use for the Site. Table 1. Proposed land use for the Site (in acres) Land Use Existing Site (acres) Proposed Site (acres) Change Buildings 0.02 0.11 + 0.09 Green Roof 0.00 0.02 + 0.02 Site Pavement 0.32 0.22 - 0.10 Permeable Pavers 0.00 0.02 + 0.02 Landscaped Areas 0.61 0.58 - 0.03 Total 0.95 0.95 --- Stormwater Management System The Site will include the installation of a stormwater management system that is being designed to meet the MassDEP Stormwater Management Standards and the City of Northampton Regulations. As a redevelopment, the Project is required to meet the Stormwater Management Standards to the maximum extent practicable as described in Section 5. The Project has been designed using environmentally-sensitive site design and LID techniques. This design prevents the generation of stormwater and non-point source pollution by reducing impervious surfaces with porous pavers, disconnecting flow paths, treating stormwater at its source, and protecting natural processes. Stormwater systems have been designed to model natural hydrologic features. The proposed stormwater management system for the Project will include permeable pavers, proprietary treatment structures, landscape filters, grassed swales, a green roof, and lined bioretention basins. All stormwater generated by the Site makes its way southwest across the site either piped or overland. Overflow from the proposed BMPs will be discharged to the existing drainage main in College Lane. Permeable Pavers and Grass Pave Three (3) permeable pavers systems totaling approximately 860 square feet, are proposed as part of this project. Additionally, there are two (2) areas with Grass Pave surface, totaling approximately 480 square feet. These 4 areas are pedestrian only, and therefore will not be subject to significant pollutant loadings. Due to the perched groundwater table and the clay/silt layers, these systems are lined and will not provide infiltration and are intended for water quality and rate reduction only. The permeable pavers will replace traditional impervious walkway area and allow runoff to be treated within the pavement section. Because of poor soils on the site and groundwater, these areas will be lined and will not be infiltrating. The filter course and reservoir course were sized according to the University of New Hampshire Design Specifications for Porous Asphalt Pavement and Infiltration Beds. Bioretention Basins Eleven (11) bioretention basins are proposed to treat stormwater runoff generated by the landscaped site and site walkways. The bioretention basin includes a minimum 24-inch media filter to provide TSS and nutrient pollutant removal. Due to the perched groundwater table and the clay/silt layers, these systems are lined and will not provide infiltration and are intended for water quality and rate reduction only. These areas are pedestrian only, and therefore will not be subject to significant pollutant loadings. Water Quality Structures Five (5) silt prison inlet structures are proposed on Chapin Way and College Lane in place of the existing catch basin structures. The first inlet is located to the north of the 8 College Lane building. This catch basin was adjacent to the limit of work, but in the existing condition it discharges to the sewer, so this area was ultimately included in the limit of work in order remediate this condition and connect it to site drainage. Of the other four, three are located adjacent to the raised table in College Lane at the southwest corner of the site, and the last is in Chapin Way across from the Wesley House. These existing catch basin structures will be retrofitted with the silt prison insert and will provide additional Total Phosphorus and TSS removal for the site. Green Roof 1000 square feet of green roof is proposed on the building. Green roof provides peak rate attenuation by plant uptake and evapotranspiration. The Green roof will consist of a minimum of a 4-inch-thick drainage layer that will store collected rainfall for smaller storm events. The Green roof system will overflow to the building’s plumbing system and then to the underground landscape filter section prior to discharging to the drain main that passes through the project site. Bioretention Landscape Filters (Biofiltration) Bioretention landscape filters are proposed to treat stormwater runoff generated by the proposed surrounding pedestrian and landscaped areas. The bioretention landscape filters include a minimum 24-inch media filter to provide TSS and nutrient pollutant removal. Due to the perched groundwater table and the clay/silt layers, these systems are lined and will not provide infiltration and are intended for water quality and rate reduction only. Stormwater Management During Construction The Site Contractor will be responsible for stormwater management of the active construction site and is required to adhere to the conditions of the 2017 Construction General Permit under the Environmental Protection Agency through the preparation and implementation of a Stormwater Pollution Prevention Plan (SWPPP). A draft SWPPP has been prepared in accordance with the MassDEP Stormwater Management Standards and the 2017 Construction General Permit (Appendix F). Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 5 SECTION 4 Stormwater Management Analysis Methodology Nitsch Engineering completed a hydrologic analysis of the existing project site utilizing Soil Conservation Service (SCS) Runoff Curve Number (CN) methodology. The SCS method calculates the rate at which the runoff reaches the design point considering several factors: the slope and flow lengths of the subcatchment area, the soil type of the subcatchment area, and the type of surface cover in the subcatchment area. HydroCAD Version 10.00 computer modeling software was used in conjunction with the SCS method to determine the peak runoff rates and runoff volumes for the 2-, 10-, 25-, and 100-year, 24-hour storm events. The proposed project site is being analyzed with the same methodology. The Site was divided into multiple drainage areas, or subcatchments, which drain to the design points along the property boundary and within the site. For each subcatchment area, SCS Runoff Curve Numbers (CNs) were selected by using the cover type and hydrologic soil group of each area. The peak runoff rates and runoff volumes for the 2-, 10-, 25- and 100-year 24-hour storm events were then determined by inputting the drainage areas, CNs, and time of concentration (Tc) paths into the HydroCAD model. The National Oceanic and Atmospheric Administration Atlas 14 precipitation frequency estimates were used to calculate the 2-, 10-, 25-, and 100- year 24-hour storm events in HydroCAD. Refer to the HydroCAD calculations in Appendix B and C for rainfall information. HydroCAD Version 10.10 The HydroCAD computer program uses SCS and TR-20 methods to model drainage systems. TR-20 (Technical Release 20) was developed by the Soil Conservation Service to estimate runoff and peak discharges in small watersheds. TR-20 is generally accepted by engineers and reviewing authorities as the standard method for estimating runoff and peak discharges. HydroCAD Version 10.10 uses up to four types of components to analyze the hydrology of a given site: subcatchments, reaches, basins, and links. Subcatchments are areas of land that produce surface runoff. The area, weighted CN, and Tc characterize each individual subcatchment area. Reaches are generally uniform streams, channels, or pipes that convey water from one point to another. A basin is any impoundment that fills with water from one or more sources and empties via an outlet structure. Links are used to introduce hydrographs into a project from another source or to provide a junction for more than one hydrograph within a project. The time span for the model was set for 0-72 hours in order to prevent truncation of the hydrograph. Modeling of Permeable Pavers Section The permeable paver systems were modeled according to methodology developed by the University of New Hampshire Stormwater Center (UNHSC). Under ideal conditions, porous pavers with a suitable base will rapidly infiltrate several inches of water, resulting in no runoff in the traditional sense. However, the HydroCAD model needs to evaluate the “runoff” that is penetrating through the porous pavers. This requires the use of a high CN (98) to capture most of the rainfall. Once intercepted by the porous asphalt surface, the water will take some time to travel through the base layers of the roadway, before ponding in the voids of the stone base. The UNHSC has studied this behavior and developed an extended Tc value to simulate the travel time through the base. Their research determined that a Tc of 790 minutes has produced good predictions of the final discharge from porous asphalt with a 41-inch base (measured above the underdrains). It is believed that a proportional Tc can be used for a smaller base thickness, as long as the layers remain proportional and are in accordance with the UNH specifications. 6 Existing Hydrologic Conditions As summarized in Section 2.1, Nitsch Engineering delineated the project site into on-site subcatchments (watershed) areas discharging to one (1) design point utilizing an existing conditions survey and on-site observations (See Figure DR-1). The design point (DP-1) is the existing closed drainage in College Lane. The HydroCAD model for existing conditions is provided in Appendix B and results from the HydroCAD calculations are summarized below in Table 3. Proposed Hydrologic Conditions The proposed project has been designed to mitigate the change in stormwater runoff at the design point as required by the DEP Stormwater Management Standards and the City of Northampton Rules and Regulations. The existing watershed areas were modified to reflect the proposed topography, storm drainage structures and BMPs, and roof areas. (See Figure DR-2). The HydroCAD model for proposed conditions is provided in Appendix C and results from the calculations are summarized in Table 2. Peak Flow Rates The proposed stormwater management system is expected to reduce the proposed peak runoff rates to at or below the existing rates. Table 2 below summarizes the existing and proposed hydrologic analyses for the site. Table 2. Peak Rates of Runoff in Cubic Feet per Second (cfs) Storm Event 2-year 10-year 25-year 100-year DP-1 Existing 2.01 3.79 4.91 6.62 Proposed 1.46 2.75 3.76 5.10 Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 7 SECTION 5 City of Northampton Stormwater Regulations The City of Northampton has additional design considerations required for stormwater as summarized below. LID Design Strategies The City’s Stormwater Management Rules and Regulations indicate that low impact design (LID) strategies must be implemented unless infeasible in order to reduce the discharge of stormwater from development sites. The project will include eleven (11) bioretention basins, green roof, landscape filters, and porous paver areas to treat and mitigate peak runoff rates. Bioretention basins were located where site programing allowed for them and were designed to be lined systems because there was not adequate separation from the bottom of the basin and groundwater. Annual Load Reduction of Phosphorus (50%) and TSS (80%) The Northampton Stormwater Management Rules and Regulations require redevelopments to meet the minimum requirements of the MS4 permit by including removal of 80% of the average annual load of Total Suspended Solids and 50% of the average annual load of Total Phosphorus. The proposed project is expected to reduce phosphorus loads in the post-construction condition by 66% and TSS loads by 80% by using a combination of bioretention basins, permeable pavers, landscape filters, deep- sump and hooded catch basins, and silt prison inlets. In addition, an Operations and Maintenance plan that calls for catch basin cleaning, sweeping of the vehicular impervious surfaces on-site, and litter removal will allow for additional phosphorus reductions. Refer to Appendix H for the Phosphorus and TSS Removal Calculations. Annual Load Reduction of Nitrogen In addition to the Phosphorus and TSS removal requirements as outlined above, the City of Northampton requires stormwater BMPs to be optimized for Nitrogen removal. The Massachusetts MS4 General Permit Appendix F Attachment 3 provides Nitrogen Load reduction values for various BMPs. Each of the BMPs used for phosphorus removal also provide Nitrogen Load reduction. Refer to Appendix H for the Nitrogen Removal Calculations. 8 SECTION 6 MassDEP Stormwater Management Standards The Project is considered a redevelopment under the DEP Stormwater Management System. As such, the project is required to meet Standards 2, 3, and the pretreatment and structural best management practice requirements of Standards 4,5, and 6 only to the maximum extent practicable. Existing stormwater discharges need to comply with Standard 1 only to the maximum extent practicable. The project will comply with all other Standards. The site will be designed to meet or meet to the maximum extent practicable the MassDEP Stormwater Management Standards as summarized below: Standard 1: No New Untreated Discharges The Project will not discharge any untreated stormwater directly to or cause erosion in wetlands or waters of the Commonwealth. Stormwater from the Site will be collected and treated in accordance with the MassDEP Stormwater Management Standards and stormwater outfalls will be stabilized to prevent erosion. Standard 2: Peak Rate Attenuation The proposed stormwater management system will be designed so that the post-development peak discharge rates do not exceed pre-development peak discharge rates. To prevent storm damage and downstream flooding, the proposed stormwater management practices will mitigate peak runoff rates for the 2-, 10-, 25- and 100-year, 24-hour storm events. Refer to Table 3 for a pre- and post- development peak runoff rate comparison. Standard 3: Groundwater Recharge The Site was designed using environmentally-sensitive site design, low impact development techniques, and stormwater BMP treatment trains. Because of poor soils, there is no proposed infiltration on the site, however, the design results in a net decrease in impervious area to the site, which promotes additional annual groundwater recharge on the site in comparison to the existing condition. The HydroCAD reports provided in Appendix C indicate that all proposed BMPs will drain within 72 hours for the 2-, 10-, 25-, and 100-year storm events, meeting the 72-hour MassDEP drawdown requirement. No infiltration is proposed on site. Standard 4: Water Quality Treatment The proposed stormwater management system will be designed to remove greater than 80% of the average annual post-construction load of Total Suspended Solids (TSS). Structural stormwater BMPs including a Silt Prison, bioretention basins, and porous pavers, are sized to capture the required water quality volume (1 inch over the project site) and remove a minimum of 80% of total suspended solids. Table 3. Proposed Treatment Train Summary Watershed Treatment Train PR1-PR11 Bioretention Basin  Discharge PR16 Silt Prison  Discharge PR13, PR12 Permeable Pavers  Discharge PR14 Permeable Pavers  Bioretention Basin  Discharge PR15 Green Roof  Biofiltration (Landscape filter)  Discharge Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 9 The Permeable paver sections were designed in accordance with the University of New Hampshire Design Specifications for Porous Asphalt Pavement and Infiltration Beds and include an 18-inch filter course of bank run gravel to provide water quality treatment prior to flowing into the reservoir course. TSS removal calculation spreadsheets are provided in Appendix H. Source control and pollution prevention measures, such as vacuum cleaning, street sweeping, proper snow management, and stabilization of eroded surfaces, are included in the Long-Term Pollution Prevention Plan and Operation and Maintenance Plan (Appendix E). Standard 5: Land Uses with Higher Potential Pollutant Loads The Project is not considered a LUHPPL and therefore, this standard is not applicable. Standard 6: Critical Areas The Mill River/Paradise Pond is identified as a Cold-Water Fisheries Habitat by the Massachusetts Division of Fisheries and Wildlife. BMPs complying with Standard 6 have been chosen to provide water quality, including bioretention basins, permeable pavers with a filter course, biofiltration (landscape filter), and green roof. Standard 7: Redevelopments The Project is considered a redevelopment under the MassDEP Stormwater Management Standards. Therefore, the project is required to meet Standard 2, Standard 3, and the pretreatment and structural stormwater BMP requirements of Standards 4, 5, and 6 to the maximum extent practicable. The projects should comply with all other requirements of the Stormwater Management Standards and improve existing conditions. The Project meets this standard. Standard 8: Construction Period Pollution Prevention and Sedimentation Control A plan to control construction-related impacts, including erosion, sedimentation, and other pollutant sources during construction and land disturbance activities (construction period erosion, sedimentation, and pollution prevention plan) will be developed and implemented during the Notice of Intent permitting process. Due to how close the project area is to one (1) acre, to be conservative, the Project will be submitting a Notice of Intent to the Environmental Protection Agency (EPA) for coverage under the National Pollution Discharge Elimination System (NPDES) Construction General Permit. As part of this application the Applicant is required to prepare a Stormwater Pollution Prevention Plan (SWPPP) and implement the measures in the SWPPP. The SWPPP, which is to be kept on site, includes erosion and sediment controls (stabilization practices and structural practices), temporary and permanent stormwater management measures, Contractor inspection schedules and reporting of all SWPPP features, materials management, waste disposal, off-site vehicle tracking, spill prevention and response, sanitation, and non-stormwater discharges. A draft SWPPP is provided in Appendix F. Standard 9: Operation and Maintenance Plan A post-construction operation and maintenance plan has been prepared and will be implemented to ensure that stormwater management systems function as designed. Source control and stormwater BMP operation requirements for the site are summarized in the Long-Term Pollution Prevention Plan and Operation and Maintenance Plan provided in Appendix E. 10 Standard 10: Prohibition of Illicit Discharges There will be no illicit discharges to the stormwater management system associated with the Project. An Illicit Discharge Compliance Statement is provided in Appendix A. SECTION 7 Closed Drainage System Design The proposed closed drainage system consists of area drains, deep sump and hooded catch basins, drainage manholes connected with corrugated polyethylene pipe. The closed drainage system was designed to convey the 25-year storm event using the Rational method, as required by the City of Northampton. Refer to Appendix D for more information. SECTION 8 Conclusion In conclusion, the Project’s stormwater management system will reduce or maintain peak runoff rates through the widespread use of filtration BMPs and improve the water quality of stormwater being discharged from the Site. Environmentally sensitive site design and low impact development techniques will be implemented throughout the Site. The Project is being designed to meet and exceed the MassDEP Stormwater Management Standards and the City of Northampton Rules and Regulations. Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 11 FIGURES DR-1 Existing Watershed Areas DR-2 Proposed Watershed Areas Figure 1 - USGS Aerial Map Figure 2 - USGS Locus Map Figure 3 - NHESP Map Figure 4 - Wetlands Map Figure 5 - FEMA Flood Map PARK ANNEX HOPKINS HOUSE WESLEY HOUSE HAVENHOUSE CHAPIN HOUSE LYMANCONSERVATORY 8 COLLEGELANE ADMISSION'SOFFICE COLLEGE LANETenBerke Architects D.P.C. 41 Madison Avenue, 17th FloorNew York NY 10001212 229 9211 TenBerke.com 2023 TenBerke Architects D.P.C.C Architect: ALL WORK SHALL BE CARRIED OUT IN ACCORDANCE WITH ALLCODES AND REGULATIONS HAVING JURISDICTION OVER THISSITE LOCATION. ALL DIMENSIONS AND INFORMATION SHALL BE CHECKED ANDVERIFIED ON THE JOB AND ANY DISCREPANCIES MUST BEREPORTED TO THE ARCHITECT. THESE DRAWINGS MUST NOTBE SCALED. THE DESIGN AND CONTRACT DOCUMENTS ARE THECOPYRIGHT PROPERTY OF THE ARCHITECT AND MAY NOT BE REPRODUCED, ALTERED, OR REUSED WITHOUT THEARCHITECT'S WRITTEN APPROVAL. Project: Drawing Status: Date: Drawing History: Scale: SEAL FOR PERMIT ONLY C 6 5 4 3 2 1 A B D E CODE CONSULTANT 617.523.8227 rwsullivan.com 529 Main Street, Suite 203 Boston, MA 02129RW SULLIVAN GRAPHICS 1.347.529.4562 afreeman.co63 Flushing Ave., Unit 243 Brooklyn, NY 11205 A FREEMAN HARDWARE 201.398.6583 somspec.net 462 Sheffield Road Ridgewood, NJ 07450SOMSPEC ACOUSTICS / AV / IT / SECURITY 212.725.6800 www.smwllc.com275 Madison Ave New York, NY 10016 SHEN MILSON WILKE LIGHTING 212.201.5790 www.oneluxstudio.com 158 West 29th Street, 10th Floor New York, NY 10001ONE LUX STUDIO MEP-FP ENGINEER 203.663.5614 altieriseborwieber.com/171 Milk St 3rd Floor, Boston MA 02109 ALTIERI SEBOR WIEBER LLC STRUCTURAL ENGINEER / SUSTAINABILITY / FACADE 1.917.661.7800 www.thorntontomasetti.com120 Broadway 15th Floor New York, NY 10271-0016THORNTON TOMASETTI LANDSCAPE ARCHITECTURE 212.431.3609 www.mnlandscape.com120 Broadway, #1040 New York, NY 10271MNLA CIVIL ENGINEER 617.338.0063 www.nitscheng.com2 Center Plaza, Suite 430, Boston, MA 02108NITSCH ENGINEERING As indicated SMITH COLLEGE LAZARUS-WURTELE CENTER COLLEGE LNNORTHAMPTON, MA, 01063 DBP Project No. 4213 ISSUED FOR SITE PERMIT 11/01/2023 NO.DESCRIPTION DATE SITE PERMIT SUBMISSION 11/01/2023 EXISTING WATERSHED AREAS DR-1 DP-1 1"=50' PARK ANNEX HOPKINS HOUSE WESLEY HOUSE HAVENHOUSE CHAPIN HOUSE LYMANCONSERVATORY 8 COLLEGELANE ADMISSION'SOFFICE COLLEGE LANETenBerke Architects D.P.C. 41 Madison Avenue, 17th FloorNew York NY 10001212 229 9211 TenBerke.com 2023 TenBerke Architects D.P.C.C Architect: ALL WORK SHALL BE CARRIED OUT IN ACCORDANCE WITH ALLCODES AND REGULATIONS HAVING JURISDICTION OVER THISSITE LOCATION. ALL DIMENSIONS AND INFORMATION SHALL BE CHECKED ANDVERIFIED ON THE JOB AND ANY DISCREPANCIES MUST BEREPORTED TO THE ARCHITECT. THESE DRAWINGS MUST NOTBE SCALED. THE DESIGN AND CONTRACT DOCUMENTS ARE THECOPYRIGHT PROPERTY OF THE ARCHITECT AND MAY NOT BE REPRODUCED, ALTERED, OR REUSED WITHOUT THEARCHITECT'S WRITTEN APPROVAL. Project: Drawing Status: Date: Drawing History: Scale: SEAL FOR PERMIT ONLY C 6 5 4 3 2 1 A B D E CODE CONSULTANT 617.523.8227 rwsullivan.com 529 Main Street, Suite 203 Boston, MA 02129RW SULLIVAN GRAPHICS 1.347.529.4562 afreeman.co63 Flushing Ave., Unit 243 Brooklyn, NY 11205 A FREEMAN HARDWARE 201.398.6583 somspec.net 462 Sheffield Road Ridgewood, NJ 07450SOMSPEC ACOUSTICS / AV / IT / SECURITY 212.725.6800 www.smwllc.com275 Madison Ave New York, NY 10016 SHEN MILSON WILKE LIGHTING 212.201.5790 www.oneluxstudio.com 158 West 29th Street, 10th Floor New York, NY 10001ONE LUX STUDIO MEP-FP ENGINEER 203.663.5614 altieriseborwieber.com/171 Milk St 3rd Floor, Boston MA 02109 ALTIERI SEBOR WIEBER LLC STRUCTURAL ENGINEER / SUSTAINABILITY / FACADE 1.917.661.7800 www.thorntontomasetti.com120 Broadway 15th Floor New York, NY 10271-0016THORNTON TOMASETTI LANDSCAPE ARCHITECTURE 212.431.3609 www.mnlandscape.com120 Broadway, #1040 New York, NY 10271MNLA CIVIL ENGINEER 617.338.0063 www.nitscheng.com2 Center Plaza, Suite 430, Boston, MA 02108NITSCH ENGINEERING As indicated SMITH COLLEGE LAZARUS-WURTELE CENTER COLLEGE LNNORTHAMPTON, MA, 01063 DBP Project No. 4213 ISSUED FOR SITE PERMIT 11/01/2023 NO.DESCRIPTION DATE SITE PERMIT SUBMISSION 11/01/2023 PROPOSED WATERSHED AREAS DR-2 DP-1 1"=50' Prospect Street Elm S t r e e tParadise RoadColl egeLaneRound Hill RoadC hapinDriveHenshawAvenue 79 ELM ST 109 ELM ST 90 ELM ST HENSHAWAVE 137 ELM ST COLLEGE LANE 10 HENSHAW AVE ELMST MILLRIVER ELM ST COLLEGELANE COLLEGELANE COLLEGE LANE ELMST 105 ELM ST COLLEGE LANE 16 PARADISE RD ELMST 18 HENSHAW AVE COLLEGELANE 123 ELM ST COLLEGE LANE ELM ST 112 ELM ST 156 ELM ST 115 ELM ST COLLEGE LANE 84 ELM ST 8 COLLEGE LANE 19 ROUND HILL RD 138 ELM ST 7 COLLEGE LANE 21 HENSHAW AVE 20 ROUND HILL RD 149 ELM ST ELM ST COLLEGE LANE . Scale: 1"=200' 0 200 400100 Feet Path: \\jnei.local\DFS\Projects\15000-16999\15150 SmithCollege\Civil\GIS\15150_date20231026_SmithCollege_NOI\15150_date20231026_SmithCollege_NOI.aprx10/26/2023Aerial Locus Data Source: MassGIS Nitsch Project #15150 8 College Lane Northampton, MA, 01063 Massachusetts Parcels Project Site .Path: \\jnei.local\DFS\Projects\15000-16999\15150 SmithCollege\Civil\GIS\15150_date20231026_SmithCollege_NOI\15150_date20231026_SmithCollege_NOI.aprx10/26/2023USGS Locus Data Source: USGS Nitsch Project #15150 8 College Lane Northampton, MA, 01063 Scale: 1"=800' 0 800 1,600400 Feet Project Location Prospect Street Elm S t r e e tParadise RoadColl egeLaneRound Hill RoadC hapinDriveHenshawAvenue . Scale: 1"=200' 0 200 400100 Feet Path: \\jnei.local\DFS\Projects\15000-16999\15150 SmithCollege\Civil\GIS\15150_date20231026_SmithCollege_NOI\15150_date20231026_SmithCollege_NOI.aprx10/26/2023Natural Heritage and Endangered Species Program Data Source: MassGIS Nitsch Project #15150 8 College Lane Northampton, MA, 01063 Massachusetts Parcels Property Lines NHESP Areas NHESP Priority Habitats ofRare Species NHESP Estimated Habitats of Rare Wildlife Project Location Prospect Street Elm S t r e e tParadise RoadColl egeLaneRound Hill RoadC hapinDriveHenshawAvenue .Path: \\jnei.local\DFS\Projects\15000-16999\15150 SmithCollege\Civil\GIS\15150_date20231026_SmithCollege_NOI\15150_date20231026_SmithCollege_NOI.aprx10/26/2023 Data Source: MassGIS Nitsch Project #15150 8 College Lane Northampton, MA, 01063 MassDEP Wetlands Scale: 1"=200' 0 200 400100 Feet Massachusetts Parcels Property Lines MassDEP Wetlands Shoreline Open Water Project Location ElmStreet ProspectStreetWestStreetBedfordTerraceParadise RoadHarrisonAvenue RoundHillRoadCol l egeLaneBelmon tAvenueGreenStre e t Factory StreetNei lson Dr iveFranklinStreet Tyler Co u r t M and elle R o a d Seelye Driv e Arnold AvenueKensingtonAvenueTylerDriveSadieWilliamsWay ChapinDriv eCrescentStreet Barrett PlaceLangworthyRoad Henshaw Avenue.Path: \\jnei.local\DFS\Projects\15000-16999\15150 SmithCollege\Civil\GIS\15150_date20231026_SmithCollege_NOI\15150_date20231026_SmithCollege_NOI.aprx10/26/2023FEMA Flood Hazard Data Source: MassGIS, MassEOEEA Nitsch Project #15150 8 College Lane Northampton, MA, 01063 Scale: 1"=400' 0 400 800200 Feet Massachusetts Parcels Property Lines FEMA Q3 Flood Zones (where no NFHLdata exists) AE: 100-year Flooding, withBFE X500: 500-year Flooding Project Location 12 APPENDIX A Stormwater Management Standards Documentation MassDEP Checklist for Stormwater Report Standard 10: Illicit Discharge Compliance Statement MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 1 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report A. Introduction Important: When filling out forms on the computer, use only the tab key to move your cursor - do not use the return key. A Stormwater Report must be submitted with the Notice of Intent permit application to document compliance with the Stormwater Management Standards. The following checklist is NOT a substitute for the Stormwater Report (which should provide more substantive and detailed information) but is offered here as a tool to help the applicant organize their Stormwater Management documentation for their Report and for the reviewer to assess this information in a consistent format. As noted in the Checklist, the Stormwater Report must contain the engineering computations and supporting information set forth in Volume 3 of the Massachusetts Stormwater Handbook. The Stormwater Report must be prepared and certified by a Registered Professional Engineer (RPE) licensed in the Commonwealth. The Stormwater Report must include: • The Stormwater Checklist completed and stamped by a Registered Professional Engineer (see page 2) that certifies that the Stormwater Report contains all required submittals.1 This Checklist is to be used as the cover for the completed Stormwater Report. • Applicant/Project Name • Project Address • Name of Firm and Registered Professional Engineer that prepared the Report • Long-Term Pollution Prevention Plan required by Standards 4-6 • Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan required by Standard 82 • Operation and Maintenance Plan required by Standard 9 In addition to all plans and supporting information, the Stormwater Report must include a brief narrative describing stormwater management practices, including environmentally sensitive site design and LID techniques, along with a diagram depicting runoff through the proposed BMP treatment train. Plans are required to show existing and proposed conditions, identify all wetland resource areas, NRCS soil types, critical areas, Land Uses with Higher Potential Pollutant Loads (LUHPPL), and any areas on the site where infiltration rate is greater than 2.4 inches per hour. The Plans shall identify the drainage areas for both existing and proposed conditions at a scale that enables verification of supporting calculations. As noted in the Checklist, the Stormwater Management Report shall document compliance with each of the Stormwater Management Standards as provided in the Massachusetts Stormwater Handbook. The soils evaluation and calculations shall be done using the methodologies set forth in Volume 3 of the Massachusetts Stormwater Handbook. To ensure that the Stormwater Report is complete, applicants are required to fill in the Stormwater Report Checklist by checking the box to indicate that the specified information has been included in the Stormwater Report. If any of the information specified in the checklist has not been submitted, the applicant must provide an explanation. The completed Stormwater Report Checklist and Certification must be submitted with the Stormwater Report. 1 The Stormwater Report may also include the Illicit Discharge Compliance Statement required by Standard 10. If not included in the Stormwater Report, the Illicit Discharge Compliance Statement must be submitted prior to the discharge of stormwater runoff to the post-construction best management practices. 2 For some complex projects, it may not be possible to include the Construction Period Erosion and Sedimentation Control Plan in the Stormwater Report. In that event, the issuing authority has the discretion to issue an Order of Conditions that approves the project and includes a condition requiring the proponent to submit the Construction Period Erosion and Sedimentation Control Plan before commencing any land disturbance activity on the site. MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 2 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report B. Stormwater Checklist and Certification The following checklist is intended to serve as a guide for applicants as to the elements that ordinarily need to be addressed in a complete Stormwater Report. The checklist is also intended to provide conservation commissions and other reviewing authorities with a summary of the components necessary for a comprehensive Stormwater Report that addresses the ten Stormwater Standards. Note: Because stormwater requirements vary from project to project, it is possible that a complete Stormwater Report may not include information on some of the subjects specified in the Checklist. If it is determined that a specific item does not apply to the project under review, please note that the item is not applicable (N.A.) and provide the reasons for that determination. A complete checklist must include the Certification set forth below signed by the Registered Professional Engineer who prepared the Stormwater Report. Registered Professional Engineer’s Certification I have reviewed the Stormwater Report, including the soil evaluation, computations, Long-term Pollution Prevention Plan, the Construction Period Erosion and Sedimentation Control Plan (if included), the Long- term Post-Construction Operation and Maintenance Plan, the Illicit Discharge Compliance Statement (if included) and the plans showing the stormwater management system, and have determined that they have been prepared in accordance with the requirements of the Stormwater Management Standards as further elaborated by the Massachusetts Stormwater Handbook. I have also determined that the information presented in the Stormwater Checklist is accurate and that the information presented in the Stormwater Report accurately reflects conditions at the site as of the date of this permit application. Registered Professional Engineer Block and Signature Signature and Date Checklist Project Type: Is the application for new development, redevelopment, or a mix of new and redevelopment? New development Redevelopment Mix of New Development and Redevelopment 2023/01/01 NITSCH#15150 MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 3 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) LID Measures: Stormwater Standards require LID measures to be considered. Document what environmentally sensitive design and LID Techniques were considered during the planning and design of the project: No disturbance to any Wetland Resource Areas Site Design Practices (e.g. clustered development, reduced frontage setbacks) Reduced Impervious Area (Redevelopment Only) Minimizing disturbance to existing trees and shrubs LID Site Design Credit Requested: Credit 1 Credit 2 Credit 3 Use of “country drainage” versus curb and gutter conveyance and pipe Bioretention Cells (includes Rain Gardens) Constructed Stormwater Wetlands (includes Gravel Wetlands designs) Treebox Filter Water Quality Swale Grass Channel Green Roof Other (describe): Permeable Pavers, Landscape filters Standard 1: No New Untreated Discharges No new untreated discharges Outlets have been designed so there is no erosion or scour to wetlands and waters of the Commonwealth Supporting calculations specified in Volume 3 of the Massachusetts Stormwater Handbook included. MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 4 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 2: Peak Rate Attenuation Standard 2 waiver requested because the project is located in land subject to coastal storm flowage and stormwater discharge is to a wetland subject to coastal flooding. Evaluation provided to determine whether off-site flooding increases during the 100-year 24-hour storm. Calculations provided to show that post-development peak discharge rates do not exceed pre- development rates for the 2-year and 10-year 24-hour storms. If evaluation shows that off-site flooding increases during the 100-year 24-hour storm, calculations are also provided to show that post-development peak discharge rates do not exceed pre-development rates for the 100-year 24- hour storm. Standard 3: Recharge Soil Analysis provided. Required Recharge Volume calculation provided. Required Recharge volume reduced through use of the LID site Design Credits. Sizing the infiltration, BMPs is based on the following method: Check the method used. Static Simple Dynamic Dynamic Field1 Runoff from all impervious areas at the site discharging to the infiltration BMP. Runoff from all impervious areas at the site is not discharging to the infiltration BMP and calculations are provided showing that the drainage area contributing runoff to the infiltration BMPs is sufficient to generate the required recharge volume. Recharge BMPs have been sized to infiltrate the Required Recharge Volume. Recharge BMPs have been sized to infiltrate the Required Recharge Volume only to the maximum extent practicable for the following reason: Site is comprised solely of C and D soils and/or bedrock at the land surface M.G.L. c. 21E sites pursuant to 310 CMR 40.0000 Solid Waste Landfill pursuant to 310 CMR 19.000 Project is otherwise subject to Stormwater Management Standards only to the maximum extent practicable. Calculations showing that the infiltration BMPs will drain in 72 hours are provided. Property includes a M.G.L. c. 21E site or a solid waste landfill and a mounding analysis is included. 1 80% TSS removal is required prior to discharge to infiltration BMP if Dynamic Field method is used. MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 5 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 3: Recharge (continued) The infiltration BMP is used to attenuate peak flows during storms greater than or equal to the 10- year 24-hour storm and separation to seasonal high groundwater is less than 4 feet and a mounding analysis is provided. Documentation is provided showing that infiltration BMPs do not adversely impact nearby wetland resource areas. Standard 4: Water Quality The Long-Term Pollution Prevention Plan typically includes the following: • Good housekeeping practices; • Provisions for storing materials and waste products inside or under cover; • Vehicle washing controls; • Requirements for routine inspections and maintenance of stormwater BMPs; • Spill prevention and response plans; • Provisions for maintenance of lawns, gardens, and other landscaped areas; • Requirements for storage and use of fertilizers, herbicides, and pesticides; • Pet waste management provisions; • Provisions for operation and management of septic systems; • Provisions for solid waste management; • Snow disposal and plowing plans relative to Wetland Resource Areas; • Winter Road Salt and/or Sand Use and Storage restrictions; • Street sweeping schedules; • Provisions for prevention of illicit discharges to the stormwater management system; • Documentation that Stormwater BMPs are designed to provide for shutdown and containment in the event of a spill or discharges to or near critical areas or from LUHPPL; • Training for staff or personnel involved with implementing Long-Term Pollution Prevention Plan; • List of Emergency contacts for implementing Long-Term Pollution Prevention Plan. A Long-Term Pollution Prevention Plan is attached to Stormwater Report and is included as an attachment to the Wetlands Notice of Intent. Treatment BMPs subject to the 44% TSS removal pretreatment requirement and the one inch rule for calculating the water quality volume are included, and discharge: is within the Zone II or Interim Wellhead Protection Area is near or to other critical areas is within soils with a rapid infiltration rate (greater than 2.4 inches per hour) involves runoff from land uses with higher potential pollutant loads. The Required Water Quality Volume is reduced through use of the LID site Design Credits. Calculations documenting that the treatment train meets the 80% TSS removal requirement and, if applicable, the 44% TSS removal pretreatment requirement, are provided. MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 6 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 4: Water Quality (continued) The BMP is sized (and calculations provided) based on: The ½” or 1” Water Quality Volume or The equivalent flow rate associated with the Water Quality Volume and documentation is provided showing that the BMP treats the required water quality volume. The applicant proposes to use proprietary BMPs, and documentation supporting use of proprietary BMP and proposed TSS removal rate is provided. This documentation may be in the form of the propriety BMP checklist found in Volume 2, Chapter 4 of the Massachusetts Stormwater Handbook and submitting copies of the TARP Report, STEP Report, and/or other third party studies verifying performance of the proprietary BMPs. A TMDL exists that indicates a need to reduce pollutants other than TSS and documentation showing that the BMPs selected are consistent with the TMDL is provided. Standard 5: Land Uses With Higher Potential Pollutant Loads (LUHPPLs) The NPDES Multi-Sector General Permit covers the land use and the Stormwater Pollution Prevention Plan (SWPPP) has been included with the Stormwater Report. The NPDES Multi-Sector General Permit covers the land use and the SWPPP will be submitted prior to the discharge of stormwater to the post-construction stormwater BMPs. The NPDES Multi-Sector General Permit does not cover the land use. LUHPPLs are located at the site and industry specific source control and pollution prevention measures have been proposed to reduce or eliminate the exposure of LUHPPLs to rain, snow, snow melt and runoff, and been included in the long term Pollution Prevention Plan. All exposure has been eliminated. All exposure has not been eliminated and all BMPs selected are on MassDEP LUHPPL list. The LUHPPL has the potential to generate runoff with moderate to higher concentrations of oil and grease (e.g. all parking lots with >1000 vehicle trips per day) and the treatment train includes an oil grit separator, a filtering bioretention area, a sand filter or equivalent. Standard 6: Critical Areas The discharge is near or to a critical area and the treatment train includes only BMPs that MassDEP has approved for stormwater discharges to or near that particular class of critical area. Critical areas and BMPs are identified in the Stormwater Report. MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 7 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 7: Redevelopments and Other Projects Subject to the Standards only to the maximum extent practicable The project is subject to the Stormwater Management Standards only to the maximum Extent Practicable as a: Limited Project Small Residential Projects: 5-9 single family houses or 5-9 units in a multi-family development provided there is no discharge that may potentially affect a critical area. Small Residential Projects: 2-4 single family houses or 2-4 units in a multi-family development with a discharge to a critical area Marina and/or boatyard provided the hull painting, service and maintenance areas are protected from exposure to rain, snow, snow melt and runoff Bike Path and/or Foot Path Redevelopment Project Redevelopment portion of mix of new and redevelopment. Certain standards are not fully met (Standard No. 1, 8, 9, and 10 must always be fully met) and an explanation of why these standards are not met is contained in the Stormwater Report. The project involves redevelopment and a description of all measures that have been taken to improve existing conditions is provided in the Stormwater Report. The redevelopment checklist found in Volume 2 Chapter 3 of the Massachusetts Stormwater Handbook may be used to document that the proposed stormwater management system (a) complies with Standards 2, 3 and the pretreatment and structural BMP requirements of Standards 4-6 to the maximum extent practicable and (b) improves existing conditions. Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan must include the following information: • Narrative; • Construction Period Operation and Maintenance Plan; • Names of Persons or Entity Responsible for Plan Compliance; • Construction Period Pollution Prevention Measures; • Erosion and Sedimentation Control Plan Drawings; • Detail drawings and specifications for erosion control BMPs, including sizing calculations; • Vegetation Planning; • Site Development Plan; • Construction Sequencing Plan; • Sequencing of Erosion and Sedimentation Controls; • Operation and Maintenance of Erosion and Sedimentation Controls; • Inspection Schedule; • Maintenance Schedule; • Inspection and Maintenance Log Form. A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan containing the information set forth above has been included in the Stormwater Report. MassDEP SW Checklist [review and need signature] • 04/01/08 Stormwater Report Checklist • Page 8 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control (continued) The project is highly complex and information is included in the Stormwater Report that explains why it is not possible to submit the Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan with the application. A Construction Period Pollution Prevention and Erosion and Sedimentation Control has not been included in the Stormwater Report but will be submitted before land disturbance begins. The project is not covered by a NPDES Construction General Permit. The project is covered by a NPDES Construction General Permit and a copy of the SWPPP is in the Stormwater Report. The project is covered by a NPDES Construction General Permit but no SWPPP been submitted. The SWPPP will be submitted BEFORE land disturbance begins. Standard 9: Operation and Maintenance Plan The Post Construction Operation and Maintenance Plan is included in the Stormwater Report and includes the following information: Name of the stormwater management system owners; Party responsible for operation and maintenance; Schedule for implementation of routine and non-routine maintenance tasks; Plan showing the location of all stormwater BMPs maintenance access areas; Description and delineation of public safety features; Estimated operation and maintenance budget; and Operation and Maintenance Log Form. The responsible party is not the owner of the parcel where the BMP is located and the Stormwater Report includes the following submissions: A copy of the legal instrument (deed, homeowner’s association, utility trust or other legal entity) that establishes the terms of and legal responsibility for the operation and maintenance of the project site stormwater BMPs; A plan and easement deed that allows site access for the legal entity to operate and maintain BMP functions. Standard 10: Prohibition of Illicit Discharges The Long-Term Pollution Prevention Plan includes measures to prevent illicit discharges; An Illicit Discharge Compliance Statement is attached; NO Illicit Discharge Compliance Statement is attached but will be submitted prior to the discharge of any stormwater to post-construction BMPs. STANDARD 10: Illicit Discharge Compliance Statement Project Name: Smith College Lazarus Wurtele Center Nitsch Project #: 15150 Location: College Lane, Northampton MA Checked by: CMH Prepared by: SEK Sheet No. 1 of 1 Date: 10/29/2023 Standard 10 states: All illicit discharges to the stormwater management system are prohibited. This is to verify: 1. Based on the information available there are no known or suspected illicit discharges to the stormwater management system at the Lazarus Wurtele Center site as defined in the MassDEP Stormwater Handbook. 2. The design of the stormwater system includes no proposed illicit discharges. Coleman Horsley, PE Date 11/01/2023 NITSCH#15150 11/01/2023 Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 13 APPENDIX B Existing Conditions – HydroCAD Calculations EXEXExisting SiteDP-EXExisting SiteRouting Diagram for 15150_HydroCAD-10-25-2023Prepared by Nitsch Engineering, Printed 10/31/2023HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSubcatReachPondLink15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 2HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCRainfall Events Listing (selected events)Event# EventNameStorm Type Curve Mode Duration(hours)B/B Depth(inches)AMC1 2-YR NOAA 24-hr D Default 24.00 1 3.08 22 10-YR NOAA 24-hr D Default 24.00 1 4.94 23 25-YR NOAA 24-hr D Default 24.00 1 6.10 24 100-YR NOAA 24-hr D Default 24.00 1 7.89 2 15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 3HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCArea Listing (selected nodes)Area(sq-ft)CN Description(subcatchment-numbers)26,394 80 >75% Grass cover, Good, HSG D (EX)13,938 98 Impervious (EX)1,003 98 Roof (EX)41,335 87 TOTAL AREA15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 4HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSoil Listing (selected nodes)Area(sq-ft)SoilGroupSubcatchmentNumbers0 HSG A0 HSG B0 HSG C26,394 HSG D EX14,941 Other EX41,335 TOTAL AREA 15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 5HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCGround Covers (selected nodes)HSG-A(sq-ft)HSG-B(sq-ft)HSG-C(sq-ft)HSG-D(sq-ft)Other(sq-ft)Total(sq-ft)GroundCoverSubcatchmentNumbers0 0 0 26,394 0 26,394 >75% Grass cover, Good0 0 0 0 13,938 13,938 Impervious0 0 0 0 1,003 1,003 Roof0 0 0 26,394 14,941 41,335 TOTAL AREANOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 6HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=41,335 sf 36.15% Impervious Runoff Depth=1.81"Subcatchment EX: Existing Site Tc=6.0 min CN=87 Runoff=2.01 cfs 6,232 cf Inflow=2.01 cfs 6,232 cfReach DP-EX: Existing Site Outflow=2.01 cfs 6,232 cfTotal Runoff Area = 41,335 sf Runoff Volume = 6,232 cf Average Runoff Depth = 1.81"63.85% Pervious = 26,394 sf 36.15% Impervious = 14,941 sf NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 7HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment EX: Existing SiteRunoff = 2.01 cfs @ 12.13 hrs, Volume= 6,232 cf, Depth= 1.81" Routed to Reach DP-EX : Existing SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 13,938 98 Impervious* 1,003 98 Roof26,394 80 >75% Grass cover, Good, HSG D41,335 87 Weighted Average26,394 63.85% Pervious Area14,941 36.15% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment EX: Existing SiteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)210NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=41,335 sfRunoff Volume=6,232 cfRunoff Depth=1.81"Tc=6.0 minCN=872.01 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 8HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-EX: Existing Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,335 sf, 36.15% Impervious, Inflow Depth = 1.81" for 2-YR eventInflow = 2.01 cfs @ 12.13 hrs, Volume= 6,232 cfOutflow = 2.01 cfs @ 12.13 hrs, Volume= 6,232 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-EX: Existing SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)210Inflow Area=41,335 sf2.01 cfs2.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 9HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=41,335 sf 36.15% Impervious Runoff Depth=3.51"Subcatchment EX: Existing Site Tc=6.0 min CN=87 Runoff=3.79 cfs 12,093 cf Inflow=3.79 cfs 12,093 cfReach DP-EX: Existing Site Outflow=3.79 cfs 12,093 cfTotal Runoff Area = 41,335 sf Runoff Volume = 12,093 cf Average Runoff Depth = 3.51"63.85% Pervious = 26,394 sf 36.15% Impervious = 14,941 sfNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 10HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment EX: Existing SiteRunoff = 3.79 cfs @ 12.13 hrs, Volume= 12,093 cf, Depth= 3.51" Routed to Reach DP-EX : Existing SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 13,938 98 Impervious* 1,003 98 Roof26,394 80 >75% Grass cover, Good, HSG D41,335 87 Weighted Average26,394 63.85% Pervious Area14,941 36.15% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment EX: Existing SiteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)43210NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=41,335 sfRunoff Volume=12,093 cfRunoff Depth=3.51"Tc=6.0 minCN=873.79 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 11HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-EX: Existing Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,335 sf, 36.15% Impervious, Inflow Depth = 3.51" for 10-YR eventInflow = 3.79 cfs @ 12.13 hrs, Volume= 12,093 cfOutflow = 3.79 cfs @ 12.13 hrs, Volume= 12,093 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-EX: Existing SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)43210Inflow Area=41,335 sf3.79 cfs3.79 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 12HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=41,335 sf 36.15% Impervious Runoff Depth=4.61"Subcatchment EX: Existing Site Tc=6.0 min CN=87 Runoff=4.91 cfs 15,890 cf Inflow=4.91 cfs 15,890 cfReach DP-EX: Existing Site Outflow=4.91 cfs 15,890 cfTotal Runoff Area = 41,335 sf Runoff Volume = 15,890 cf Average Runoff Depth = 4.61"63.85% Pervious = 26,394 sf 36.15% Impervious = 14,941 sf NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 13HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment EX: Existing SiteRunoff = 4.91 cfs @ 12.13 hrs, Volume= 15,890 cf, Depth= 4.61" Routed to Reach DP-EX : Existing SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 13,938 98 Impervious* 1,003 98 Roof26,394 80 >75% Grass cover, Good, HSG D41,335 87 Weighted Average26,394 63.85% Pervious Area14,941 36.15% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment EX: Existing SiteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)543210NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=41,335 sfRunoff Volume=15,890 cfRunoff Depth=4.61"Tc=6.0 minCN=874.91 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 14HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-EX: Existing Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,335 sf, 36.15% Impervious, Inflow Depth = 4.61" for 25-YR eventInflow = 4.91 cfs @ 12.13 hrs, Volume= 15,890 cfOutflow = 4.91 cfs @ 12.13 hrs, Volume= 15,890 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-EX: Existing SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)543210Inflow Area=41,335 sf4.91 cfs4.91 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 15HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=41,335 sf 36.15% Impervious Runoff Depth=6.34"Subcatchment EX: Existing Site Tc=6.0 min CN=87 Runoff=6.62 cfs 21,848 cf Inflow=6.62 cfs 21,848 cfReach DP-EX: Existing Site Outflow=6.62 cfs 21,848 cfTotal Runoff Area = 41,335 sf Runoff Volume = 21,848 cf Average Runoff Depth = 6.34"63.85% Pervious = 26,394 sf 36.15% Impervious = 14,941 sfNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 16HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment EX: Existing SiteRunoff = 6.62 cfs @ 12.13 hrs, Volume= 21,848 cf, Depth= 6.34" Routed to Reach DP-EX : Existing SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 13,938 98 Impervious* 1,003 98 Roof26,394 80 >75% Grass cover, Good, HSG D41,335 87 Weighted Average26,394 63.85% Pervious Area14,941 36.15% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment EX: Existing SiteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)76543210NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=41,335 sfRunoff Volume=21,848 cfRunoff Depth=6.34"Tc=6.0 minCN=876.62 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 17HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-EX: Existing Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,335 sf, 36.15% Impervious, Inflow Depth = 6.34" for 100-YR eventInflow = 6.62 cfs @ 12.13 hrs, Volume= 21,848 cfOutflow = 6.62 cfs @ 12.13 hrs, Volume= 21,848 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-EX: Existing SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)76543210Inflow Area=41,335 sf6.62 cfs6.62 cfs 14 APPENDIX C Proposed Conditions – HydroCAD Calculations Overflow a t gradeFiltration Through BioSection Overflow a t gradeFiltration Through BioSection PRPR1Basin 1PR10Basin 10PR11Basin 11PR12West site to Area DrainPR13Pavers frontPR14Pavers NorthPR15aRoof WestPR15bRoof EastPR16Remainder of site PR17Pavers pathPR2Basin 2PR3Basin 3PR4Basin 4PR5Basin 5PR6Basin 6PR7Basin 7PR8Basin 8PR9Basin 9DP-PRProposed SiteP14" Pipe Under PathP28" PipeP34" Outlet Pipe1Surface 11SSubsurface 12Surface 22SSubsurface 23Surface 33SSubsurface 34Surface 44SSubsurface 45Surface 55SSubsurface 56Surface 66SSubsurface 67Surface 77SSubsurface 78Surface 88SSubsurface 89Surface 99SSubsurface 910Surface 1010SSubsurface 1011Surface 1111SSubsurface 1129PLandscape Filter 30PPorous Pavers31PCBDistribution Pipes33PCBDistribution Pipes PNPorous PaversPSPorous Pavers33LOn-site Closed Drainage Routing Diagram for 15150_HydroCAD-10-25-2023Prepared by Nitsch Engineering, Printed 10/31/2023HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSubcatReachPondLink15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 2HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCRainfall Events Listing (selected events)Event# EventNameStorm Type Curve Mode Duration(hours)B/B Depth(inches)AMC1 2-YR NOAA 24-hr D Default 24.00 1 3.08 22 10-YR NOAA 24-hr D Default 24.00 1 4.94 23 25-YR NOAA 24-hr D Default 24.00 1 6.10 24 100-YR NOAA 24-hr D Default 24.00 1 7.89 2 15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 3HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCArea Listing (selected nodes)Area(sq-ft)CN Description(subcatchment-numbers)25,378 80 >75% Grass cover, Good, HSG D (PR1, PR10, PR11, PR12, PR13, PR14, PR16, PR17, PR2, PR3, PR4, PR5, PR6, PR7, PR8, PR9)1,320 98 Impervious (PR4, PR9)398 98 Permeable Pavers (PR13, PR17)464 98 Porous Pavers (PR14)5,639 98 Roof (PR15a, PR15b)8,130 98 Site Impervious (PR1, PR10, PR11, PR12, PR13, PR14, PR16, PR3, PR5, PR6, PR7, PR8)41,329 87 TOTAL AREA15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 4HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSoil Listing (selected nodes)Area(sq-ft)SoilGroupSubcatchmentNumbers0 HSG A0 HSG B0 HSG C25,378 HSG D PR1, PR10, PR11, PR12, PR13, PR14, PR16, PR17, PR2, PR3, PR4, PR5, PR6, PR7, PR8, PR915,951 Other PR1, PR10, PR11, PR12, PR13, PR14, PR15a, PR15b, PR16, PR17, PR3, PR4, PR5, PR6, PR7, PR8, PR941,329 TOTAL AREA 15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 5HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCGround Covers (selected nodes)HSG-A(sq-ft)HSG-B(sq-ft)HSG-C(sq-ft)HSG-D(sq-ft)Other(sq-ft)Total(sq-ft)GroundCoverSubcatchmentNumbers0 0 0 25,378 0 25,378 >75% Grass cover, Good0 0 0 0 1,320 1,320 Impervious0 0 0 0 398 398 Permeable Pavers0 0 0 0 464 464 Porous Pavers0 0 0 0 5,639 5,639 Roof0 0 0 0 8,130 8,130 Site Impervious0 0 0 25,378 15,951 41,329 TOTAL AREA15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 6HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPipe Listing (selected nodes)Line# NodeNumberIn-Invert(feet)Out-Invert(feet)Length(feet)Slope(ft/ft)n Width(inches)Diam/Height(inches)Inside-Fill(inches)1 P1 177.18 176.18 15.0 0.0667 0.013 0.0 6.0 0.02 P2 174.50 173.66 65.0 0.0129 0.013 0.0 8.0 0.03 P3 183.17 173.00 136.0 0.0748 0.013 0.0 6.0 0.04 PN 188.43 186.00 7.0 0.3471 0.013 0.0 4.0 0.0 NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 7HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=1,918 sf 33.52% Impervious Runoff Depth=1.73"Subcatchment PR1: Basin 1 Tc=6.0 min CN=86 Runoff=0.09 cfs 277 cfRunoff Area=3,386 sf 9.57% Impervious Runoff Depth=1.44"Subcatchment PR10: Basin 10 Tc=6.0 min CN=82 Runoff=0.13 cfs 407 cfRunoff Area=2,204 sf 27.72% Impervious Runoff Depth=1.66"Subcatchment PR11: Basin 11 Tc=6.0 min CN=85 Runoff=0.10 cfs 304 cfRunoff Area=2,493 sf 1.36% Impervious Runoff Depth=1.31"Subcatchment PR12: West site to Area Drain Tc=6.0 min CN=80 Runoff=0.09 cfs 272 cfRunoff Area=2,379 sf 11.60% Impervious Runoff Depth=1.44"Subcatchment PR13: Pavers front Tc=674.0 min CN=82 Runoff=0.01 cfs 286 cfRunoff Area=676 sf 77.51% Impervious Runoff Depth=2.43"Subcatchment PR14: Pavers North Tc=674.0 min CN=94 Runoff=0.00 cfs 137 cfRunoff Area=2,750 sf 100.00% Impervious Runoff Depth=2.85"Subcatchment PR15a: Roof West Tc=6.0 min CN=98 Runoff=0.18 cfs 653 cfRunoff Area=2,889 sf 100.00% Impervious Runoff Depth=2.85"Subcatchment PR15b: Roof East Tc=6.0 min CN=98 Runoff=0.19 cfs 686 cfRunoff Area=13,694 sf 44.87% Impervious Runoff Depth=1.89"Subcatchment PR16: Remainder of site Tc=6.0 min CN=88 Runoff=0.69 cfs 2,156 cfRunoff Area=443 sf 33.86% Impervious Runoff Depth=1.73"Subcatchment PR17: Pavers path Tc=674.0 min CN=86 Runoff=0.00 cfs 64 cfRunoff Area=164 sf 0.00% Impervious Runoff Depth=1.31"Subcatchment PR2: Basin 2 Tc=6.0 min CN=80 Runoff=0.01 cfs 18 cfRunoff Area=437 sf 3.20% Impervious Runoff Depth=1.38"Subcatchment PR3: Basin 3 Tc=6.0 min CN=81 Runoff=0.02 cfs 50 cfRunoff Area=2,525 sf 10.02% Impervious Runoff Depth=1.44"Subcatchment PR4: Basin 4 Tc=6.0 min CN=82 Runoff=0.10 cfs 303 cfRunoff Area=172 sf 18.02% Impervious Runoff Depth=1.51"Subcatchment PR5: Basin 5 Tc=6.0 min CN=83 Runoff=0.01 cfs 22 cfRunoff Area=188 sf 30.32% Impervious Runoff Depth=1.66"Subcatchment PR6: Basin 6 Tc=6.0 min CN=85 Runoff=0.01 cfs 26 cfRunoff Area=458 sf 26.20% Impervious Runoff Depth=1.66"Subcatchment PR7: Basin 7 Tc=6.0 min CN=85 Runoff=0.02 cfs 63 cfNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 8HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCRunoff Area=630 sf 10.16% Impervious Runoff Depth=1.44"Subcatchment PR8: Basin 8 Tc=6.0 min CN=82 Runoff=0.02 cfs 76 cfRunoff Area=3,923 sf 27.20% Impervious Runoff Depth=1.66"Subcatchment PR9: Basin 9 Tc=6.0 min CN=85 Runoff=0.18 cfs 541 cf Inflow=1.54 cfs 6,327 cfReach DP-PR: Proposed Site Outflow=1.54 cfs 6,327 cfAvg. Flow Depth=0.09' Max Vel=4.17 fps Inflow=0.10 cfs 344 cfReach P1: 4" Pipe Under Path6.0" Round Pipe n=0.013 L=15.0' S=0.0667 '/' Capacity=1.45 cfs Outflow=0.10 cfs 344 cfAvg. Flow Depth=0.13' Max Vel=2.39 fps Inflow=0.12 cfs 832 cfReach P2: 8" Pipe8.0" Round Pipe n=0.013 L=65.0' S=0.0129 '/' Capacity=1.37 cfs Outflow=0.12 cfs 832 cfAvg. Flow Depth=0.08' Max Vel=4.22 fps Inflow=0.09 cfs 439 cfReach P3: 4" Outlet Pipe6.0" Round Pipe n=0.013 L=136.0' S=0.0748 '/' Capacity=1.53 cfs Outflow=0.09 cfs 439 cfPeak Elev=183.22' Storage=10 cf Inflow=0.09 cfs 277 cfPond 1: Surface 1 Primary=0.08 cfs 183 cf Secondary=0.00 cfs 94 cf Outflow=0.09 cfs 277 cfPeak Elev=178.20' Storage=1 cf Inflow=0.00 cfs 94 cfPond 1S: Subsurface 1 Outflow=0.00 cfs 93 cfPeak Elev=182.00' Storage=0 cf Inflow=0.09 cfs 201 cfPond 2: Surface 2 Primary=0.00 cfs 0 cf Secondary=0.09 cfs 201 cf Outflow=0.09 cfs 201 cfPeak Elev=177.88' Storage=5 cf Inflow=0.09 cfs 294 cfPond 2S: Subsurface 2 Outflow=0.09 cfs 294 cfPeak Elev=181.80' Storage=10 cf Inflow=0.02 cfs 50 cfPond 3: Surface 3 Primary=0.00 cfs 1 cf Secondary=0.00 cfs 49 cf Outflow=0.01 cfs 50 cfPeak Elev=177.40' Storage=7 cf Inflow=0.10 cfs 344 cfPond 3S: Subsurface 3 Outflow=0.10 cfs 343 cfPeak Elev=183.17' Storage=54 cf Inflow=0.10 cfs 303 cfPond 4: Surface 4 Primary=0.06 cfs 70 cf Secondary=0.01 cfs 233 cf Outflow=0.07 cfs 303 cfPeak Elev=178.25' Storage=8 cf Inflow=0.01 cfs 233 cfPond 4S: Subsurface 4 Outflow=0.01 cfs 232 cfPeak Elev=182.66' Storage=16 cf Inflow=0.06 cfs 92 cfPond 5: Surface 5 Primary=0.05 cfs 56 cf Secondary=0.00 cfs 36 cf Outflow=0.06 cfs 92 cfPeak Elev=177.77' Storage=3 cf Inflow=0.02 cfs 268 cfPond 5S: Subsurface 5 Outflow=0.02 cfs 268 cfPeak Elev=182.14' Storage=17 cf Inflow=0.06 cfs 82 cfPond 6: Surface 6 Primary=0.04 cfs 44 cf Secondary=0.00 cfs 38 cf Outflow=0.05 cfs 82 cf NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 9HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPeak Elev=177.28' Storage=3 cf Inflow=0.02 cfs 306 cfPond 6S: Subsurface 6 Outflow=0.02 cfs 306 cfPeak Elev=181.12' Storage=31 cf Inflow=0.05 cfs 107 cfPond 7: Surface 7 Primary=0.03 cfs 32 cf Secondary=0.01 cfs 75 cf Outflow=0.04 cfs 107 cfPeak Elev=176.42' Storage=13 cf Inflow=0.12 cfs 725 cfPond 7S: Subsurface 7 Outflow=0.11 cfs 724 cfPeak Elev=179.80' Storage=41 cf Inflow=0.04 cfs 108 cfPond 8: Surface 8 Primary=0.00 cfs 0 cf Secondary=0.01 cfs 108 cf Outflow=0.01 cfs 108 cfPeak Elev=174.92' Storage=13 cf Inflow=0.12 cfs 832 cfPond 8S: Subsurface 8 Outflow=0.12 cfs 832 cfPeak Elev=174.32' Storage=9 cf Inflow=0.18 cfs 541 cfPond 9: Surface 9 Primary=0.17 cfs 340 cf Secondary=0.01 cfs 201 cf Outflow=0.18 cfs 541 cfPeak Elev=170.72' Storage=9 cf Inflow=0.01 cfs 201 cfPond 9S: Subsurface 9 Outflow=0.00 cfs 200 cfPeak Elev=173.30' Storage=27 cf Inflow=0.13 cfs 407 cfPond 10: Surface 10 Primary=0.12 cfs 143 cf Secondary=0.01 cfs 264 cf Outflow=0.13 cfs 407 cfPeak Elev=168.74' Storage=6 cf Inflow=0.01 cfs 264 cfPond 10S: Subsurface 10 Outflow=0.01 cfs 264 cfPeak Elev=185.34' Storage=48 cf Inflow=0.10 cfs 439 cfPond 11: Surface 11 Primary=0.09 cfs 76 cf Secondary=0.01 cfs 363 cf Outflow=0.10 cfs 439 cfPeak Elev=183.26' Storage=11 cf Inflow=0.01 cfs 363 cfPond 11S: Subsurface 11 Outflow=0.01 cfs 363 cfPeak Elev=170.87' Storage=146 cf Inflow=0.37 cfs 1,338 cfPond 29P: Landscape Filter Outflow=0.30 cfs 1,333 cfPeak Elev=174.95' Storage=2 cf Inflow=0.00 cfs 64 cfPond 30P: Porous Pavers Outflow=0.00 cfs 63 cfPeak Elev=173.72' Inflow=0.18 cfs 653 cfPond 31P: Distribution Pipes Primary=0.18 cfs 652 cf Secondary=0.00 cfs 0 cf Outflow=0.18 cfs 653 cfPeak Elev=173.74' Inflow=0.19 cfs 686 cfPond 33P: Distribution Pipes Primary=0.19 cfs 685 cf Secondary=0.00 cfs 1 cf Outflow=0.19 cfs 686 cfPeak Elev=188.47' Storage=8 cf Inflow=0.00 cfs 137 cfPond PN: Porous Pavers4.0" Round Culvert n=0.013 L=7.0' S=0.3471 '/' Outflow=0.00 cfs 135 cfPeak Elev=174.98' Storage=5 cf Inflow=0.01 cfs 286 cfPond PS: Porous Pavers Outflow=0.01 cfs 285 cfNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 10HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLC Inflow=0.86 cfs 4,171 cfLink 33L: On-site Closed Drainage Primary=0.86 cfs 4,171 cfTotal Runoff Area = 41,329 sf Runoff Volume = 6,340 cf Average Runoff Depth = 1.84"61.40% Pervious = 25,378 sf 38.60% Impervious = 15,951 sf NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 11HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR1: Basin 1Runoff = 0.09 cfs @ 12.13 hrs, Volume= 277 cf, Depth= 1.73" Routed to Pond 1 : Surface 1Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 643 98 Site Impervious1,275 80 >75% Grass cover, Good, HSG D1,918 86 Weighted Average1,275 66.48% Pervious Area643 33.52% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR1: Basin 1RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=1,918 sfRunoff Volume=277 cfRunoff Depth=1.73"Tc=6.0 minCN=860.09 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 12HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR10: Basin 10Runoff = 0.13 cfs @ 12.13 hrs, Volume= 407 cf, Depth= 1.44" Routed to Pond 10 : Surface 10Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 324 98 Site Impervious3,062 80 >75% Grass cover, Good, HSG D3,386 82 Weighted Average3,062 90.43% Pervious Area324 9.57% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR10: Basin 10RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=3,386 sfRunoff Volume=407 cfRunoff Depth=1.44"Tc=6.0 minCN=820.13 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 13HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR11: Basin 11Runoff = 0.10 cfs @ 12.13 hrs, Volume= 304 cf, Depth= 1.66" Routed to Pond 11 : Surface 11Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 611 98 Site Impervious1,593 80 >75% Grass cover, Good, HSG D2,204 85 Weighted Average1,593 72.28% Pervious Area611 27.72% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR11: Basin 11RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.110.1050.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=2,204 sfRunoff Volume=304 cfRunoff Depth=1.66"Tc=6.0 minCN=850.10 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 14HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR12: West site to Area DrainRunoff = 0.09 cfs @ 12.13 hrs, Volume= 272 cf, Depth= 1.31" Routed to Link 33L : On-site Closed DrainageRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 34 98 Site Impervious2,459 80 >75% Grass cover, Good, HSG D2,493 80 Weighted Average2,459 98.64% Pervious Area34 1.36% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR12: West site to Area DrainRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=2,493 sfRunoff Volume=272 cfRunoff Depth=1.31"Tc=6.0 minCN=800.09 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 15HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR13: Pavers frontRunoff = 0.01 cfs @ 21.72 hrs, Volume= 286 cf, Depth= 1.44" Routed to Pond PS : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 28 98 Site Impervious* 248 98 Permeable Pavers2,103 80 >75% Grass cover, Good, HSG D2,379 82 Weighted Average2,103 88.40% Pervious Area276 11.60% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR13: Pavers frontRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0070.0070.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=2,379 sfRunoff Volume=286 cfRunoff Depth=1.44"Tc=674.0 minCN=820.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 16HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR14: Pavers NorthRunoff = 0.00 cfs @ 20.97 hrs, Volume= 137 cf, Depth= 2.43" Routed to Pond PN : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 60 98 Site Impervious* 464 98 Porous Pavers152 80 >75% Grass cover, Good, HSG D676 94 Weighted Average152 22.49% Pervious Area524 77.51% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Pavers TcSubcatchment PR14: Pavers NorthRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0030.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=676 sfRunoff Volume=137 cfRunoff Depth=2.43"Tc=674.0 minCN=940.00 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 17HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15a: Roof WestRunoff = 0.18 cfs @ 12.13 hrs, Volume= 653 cf, Depth= 2.85" Routed to Pond 31P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 2,750 98 Roof2,750 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15a: Roof WestRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=2,750 sfRunoff Volume=653 cfRunoff Depth=2.85"Tc=6.0 minCN=980.18 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 18HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15b: Roof EastRunoff = 0.19 cfs @ 12.13 hrs, Volume= 686 cf, Depth= 2.85" Routed to Pond 33P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 2,889 98 Roof2,889 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15b: Roof EastRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=2,889 sfRunoff Volume=686 cfRunoff Depth=2.85"Tc=6.0 minCN=980.19 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 19HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR16: Remainder of siteRunoff = 0.69 cfs @ 12.13 hrs, Volume= 2,156 cf, Depth= 1.89" Routed to Reach DP-PR : Proposed SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 6,144 98 Site Impervious7,550 80 >75% Grass cover, Good, HSG D13,694 88 Weighted Average7,550 55.13% Pervious Area6,144 44.87% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR16: Remainder of siteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.750.70.650.60.550.50.450.40.350.30.250.20.150.10.050NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=13,694 sfRunoff Volume=2,156 cfRunoff Depth=1.89"Tc=6.0 minCN=880.69 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 20HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR17: Pavers pathRunoff = 0.00 cfs @ 21.71 hrs, Volume= 64 cf, Depth= 1.73" Routed to Pond 30P : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 150 98 Permeable Pavers293 80 >75% Grass cover, Good, HSG D443 86 Weighted Average293 66.14% Pervious Area150 33.86% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR17: Pavers pathRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0020.0010.0010.0010.0010.0010.0010.0010.0010.0010.0000.0000.0000.00000NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=443 sfRunoff Volume=64 cfRunoff Depth=1.73"Tc=674.0 minCN=860.00 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 21HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR2: Basin 2Runoff = 0.01 cfs @ 12.13 hrs, Volume= 18 cf, Depth= 1.31" Routed to Pond 2 : Surface 2Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description164 80 >75% Grass cover, Good, HSG D164 100.00% Pervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR2: Basin 2RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=164 sfRunoff Volume=18 cfRunoff Depth=1.31"Tc=6.0 minCN=800.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 22HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR3: Basin 3Runoff = 0.02 cfs @ 12.13 hrs, Volume= 50 cf, Depth= 1.38" Routed to Pond 3 : Surface 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 14 98 Site Impervious423 80 >75% Grass cover, Good, HSG D437 81 Weighted Average423 96.80% Pervious Area14 3.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR3: Basin 3RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=437 sfRunoff Volume=50 cfRunoff Depth=1.38"Tc=6.0 minCN=810.02 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 23HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR4: Basin 4Runoff = 0.10 cfs @ 12.13 hrs, Volume= 303 cf, Depth= 1.44" Routed to Pond 4 : Surface 4Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 253 98 Impervious2,272 80 >75% Grass cover, Good, HSG D2,525 82 Weighted Average2,272 89.98% Pervious Area253 10.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR4: Basin 4RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.110.1050.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=2,525 sfRunoff Volume=303 cfRunoff Depth=1.44"Tc=6.0 minCN=820.10 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 24HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR5: Basin 5Runoff = 0.01 cfs @ 12.13 hrs, Volume= 22 cf, Depth= 1.51" Routed to Pond 5 : Surface 5Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 31 98 Site Impervious141 80 >75% Grass cover, Good, HSG D172 83 Weighted Average141 81.98% Pervious Area31 18.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR5: Basin 5RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0070.0070.0060.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=172 sfRunoff Volume=22 cfRunoff Depth=1.51"Tc=6.0 minCN=830.01 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 25HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR6: Basin 6Runoff = 0.01 cfs @ 12.13 hrs, Volume= 26 cf, Depth= 1.66" Routed to Pond 6 : Surface 6Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 57 98 Site Impervious131 80 >75% Grass cover, Good, HSG D188 85 Weighted Average131 69.68% Pervious Area57 30.32% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR6: Basin 6RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0090.0090.0080.0070.0070.0060.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=188 sfRunoff Volume=26 cfRunoff Depth=1.66"Tc=6.0 minCN=850.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 26HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR7: Basin 7Runoff = 0.02 cfs @ 12.13 hrs, Volume= 63 cf, Depth= 1.66" Routed to Pond 7 : Surface 7Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 120 98 Site Impervious338 80 >75% Grass cover, Good, HSG D458 85 Weighted Average338 73.80% Pervious Area120 26.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR7: Basin 7RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0220.0210.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=458 sfRunoff Volume=63 cfRunoff Depth=1.66"Tc=6.0 minCN=850.02 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 27HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR8: Basin 8Runoff = 0.02 cfs @ 12.13 hrs, Volume= 76 cf, Depth= 1.44" Routed to Pond 8 : Surface 8Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 64 98 Site Impervious566 80 >75% Grass cover, Good, HSG D630 82 Weighted Average566 89.84% Pervious Area64 10.16% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR8: Basin 8RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=630 sfRunoff Volume=76 cfRunoff Depth=1.44"Tc=6.0 minCN=820.02 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 28HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR9: Basin 9Runoff = 0.18 cfs @ 12.13 hrs, Volume= 541 cf, Depth= 1.66" Routed to Pond 9 : Surface 9Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 2-YR Rainfall=3.08"Area (sf) CN Description* 1,067 98 Impervious2,856 80 >75% Grass cover, Good, HSG D3,923 85 Weighted Average2,856 72.80% Pervious Area1,067 27.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR9: Basin 9RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D2-YR Rainfall=3.08"Runoff Area=3,923 sfRunoff Volume=541 cfRunoff Depth=1.66"Tc=6.0 minCN=850.18 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 29HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-PR: Proposed Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,329 sf, 38.60% Impervious, Inflow Depth = 1.84" for 2-YR eventInflow = 1.54 cfs @ 12.14 hrs, Volume= 6,327 cfOutflow = 1.54 cfs @ 12.14 hrs, Volume= 6,327 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-PR: Proposed SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)10Inflow Area=41,329 sf1.54 cfs1.54 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 30HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P1: 4" Pipe Under Path[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 1.64" for 2-YR eventInflow = 0.10 cfs @ 12.17 hrs, Volume= 344 cfOutflow = 0.10 cfs @ 12.17 hrs, Volume= 344 cf, Atten= 0%, Lag= 0.0 min Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 4.17 fps, Min. Travel Time= 0.1 minAvg. Velocity = 1.51 fps, Avg. Travel Time= 0.2 minPeak Storage= 0 cf @ 12.17 hrsAverage Depth at Peak Storage= 0.09' , Surface Width= 0.38'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.45 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 15.0' Slope= 0.0667 '/'Inlet Invert= 177.18', Outlet Invert= 176.18' NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 31HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P1: 4" Pipe Under PathInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.1050.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,519 sfAvg. Flow Depth=0.09'Max Vel=4.17 fps6.0"Round Pipen=0.013L=15.0'S=0.0667 '/'Capacity=1.45 cfs0.10 cfs0.10 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 32HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P2: 8" Pipe[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 6,492 sf, 18.21% Impervious, Inflow Depth = 1.54" for 2-YR eventInflow = 0.12 cfs @ 12.21 hrs, Volume= 832 cfOutflow = 0.12 cfs @ 12.22 hrs, Volume= 832 cf, Atten= 0%, Lag= 0.3 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 2.39 fps, Min. Travel Time= 0.5 minAvg. Velocity = 0.98 fps, Avg. Travel Time= 1.1 minPeak Storage= 3 cf @ 12.22 hrsAverage Depth at Peak Storage= 0.13' , Surface Width= 0.53'Bank-Full Depth= 0.67' Flow Area= 0.3 sf, Capacity= 1.37 cfs8.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 65.0' Slope= 0.0129 '/'Inlet Invert= 174.50', Outlet Invert= 173.66' NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 33HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P2: 8" PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=6,492 sfAvg. Flow Depth=0.13'Max Vel=2.39 fps8.0"Round Pipen=0.013L=65.0'S=0.0129 '/'Capacity=1.37 cfs0.12 cfs0.12 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 34HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P3: 4" Outlet Pipe[52] Hint: Inlet/Outlet conditions not evaluated[80] Warning: Exceeded Pond 11S by 0.01' @ 12.11 hrs (0.01 cfs 2 cf) Inflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 1.83" for 2-YR eventInflow = 0.09 cfs @ 12.14 hrs, Volume= 439 cfOutflow = 0.09 cfs @ 12.15 hrs, Volume= 439 cf, Atten= 0%, Lag= 0.4 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 4.22 fps, Min. Travel Time= 0.5 minAvg. Velocity = 1.32 fps, Avg. Travel Time= 1.7 minPeak Storage= 3 cf @ 12.15 hrsAverage Depth at Peak Storage= 0.08' , Surface Width= 0.37'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.53 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 136.0' Slope= 0.0748 '/'Inlet Invert= 183.17', Outlet Invert= 173.00' NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 35HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P3: 4" Outlet PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,880 sfAvg. Flow Depth=0.08'Max Vel=4.22 fps6.0"Round Pipen=0.013L=136.0'S=0.0748 '/'Capacity=1.53 cfs0.09 cfs0.09 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 36HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1: Surface 1Inflow Area = 1,918 sf, 33.52% Impervious, Inflow Depth = 1.73" for 2-YR eventInflow = 0.09 cfs @ 12.13 hrs, Volume= 277 cfOutflow = 0.09 cfs @ 12.15 hrs, Volume= 277 cf, Atten= 2%, Lag= 0.8 minPrimary = 0.08 cfs @ 12.15 hrs, Volume= 183 cf Routed to Pond 2 : Surface 2Secondary = 0.00 cfs @ 12.15 hrs, Volume= 94 cf Routed to Pond 1S : Subsurface 1Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.22' @ 12.15 hrs Surf.Area= 34 sf Storage= 10 cfPlug-Flow detention time= 15.9 min calculated for 277 cf (100% of inflow)Center-of-Mass det. time= 15.9 min ( 849.4 - 833.5 )Volume Invert Avail.Storage Storage Description#1 182.50' 23 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 2 0 0183.00 17 5 5183.51 55 18 23Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.08 cfs @ 12.15 hrs HW=183.22' TW=182.00' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.08 cfs @ 1.51 fps)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.15 hrs HW=183.22' TW=178.20' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 37HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1: Surface 1InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=1,918 sfPeak Elev=183.22'Storage=10 cf0.09 cfs0.09 cfs0.08 cfs0.00 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 38HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1S: Subsurface 1Inflow = 0.00 cfs @ 12.15 hrs, Volume= 94 cfOutflow = 0.00 cfs @ 12.17 hrs, Volume= 93 cf, Atten= 3%, Lag= 1.7 minPrimary = 0.00 cfs @ 12.17 hrs, Volume= 93 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.20' @ 12.17 hrs Surf.Area= 52 sf Storage= 1 cfPlug-Flow detention time= 8.4 min calculated for 93 cf (100% of inflow)Center-of-Mass det. time= 7.1 min ( 1,014.1 - 1,007.0 )Volume Invert Avail.Storage Storage Description#1 178.16' 48 cfCustom Stage Data (Prismatic) Listed below (Recalc)122 cf Overall - 1 cf Embedded = 121 cf x 40.0% Voids#2 178.17' 1 cf4.0" Round Pipe Storage Inside #1L= 11.8'49 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.16 52 0 0180.50 52 122 122Device Routing Invert Outlet Devices#1 Primary 178.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 12.17 hrs HW=178.20' TW=177.88' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.63 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 39HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1S: Subsurface 1InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0030.0030.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000Peak Elev=178.20'Storage=1 cf0.00 cfs0.00 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 40HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2: Surface 2Inflow Area = 2,082 sf, 30.88% Impervious, Inflow Depth = 1.16" for 2-YR eventInflow = 0.09 cfs @ 12.15 hrs, Volume= 201 cfOutflow = 0.09 cfs @ 12.15 hrs, Volume= 201 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routed to Pond 3 : Surface 3Secondary = 0.09 cfs @ 12.15 hrs, Volume= 201 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.00' @ 0.00 hrs Surf.Area= 2 sf Storage= 0 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= (not calculated: outflow precedes inflow)Volume Invert Avail.Storage Storage Description#1 182.00' 28 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 25 7 7183.01 60 22 28Device Routing Invert Outlet Devices#1 Secondary 182.00'4.00 cfs Exfiltration at all elevations #2 Primary 183.00'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=182.00' TW=181.50' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate ( Controls 0.00 cfs)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.15 hrs HW=182.00' TW=177.88' (Dynamic Tailwater)1=Exfiltration (Passes 0.00 cfs of 4.00 cfs potential flow) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 41HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2: Surface 2InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,082 sfPeak Elev=182.00'Storage=0 cf0.09 cfs0.09 cfs0.00 cfs0.09 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 42HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2S: Subsurface 2Inflow = 0.09 cfs @ 12.15 hrs, Volume= 294 cfOutflow = 0.09 cfs @ 12.15 hrs, Volume= 294 cf, Atten= 1%, Lag= 0.5 minPrimary = 0.09 cfs @ 12.15 hrs, Volume= 294 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.88' @ 12.15 hrs Surf.Area= 57 sf Storage= 5 cfPlug-Flow detention time= 4.1 min calculated for 294 cf (100% of inflow)Center-of-Mass det. time= 3.4 min ( 855.4 - 852.0 )Volume Invert Avail.Storage Storage Description#1 177.66' 53 cfCustom Stage Data (Prismatic) Listed below (Recalc)133 cf Overall - 1 cf Embedded = 133 cf x 40.0% Voids#2 177.67' 1 cf4.0" Round Pipe Storage Inside #1L= 10.0'54 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.66 57 0 0180.00 57 133 133Device Routing Invert Outlet Devices#1 Primary 177.67'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.09 cfs @ 12.15 hrs HW=177.88' TW=177.39' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.09 cfs @ 1.57 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 43HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2S: Subsurface 2InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Peak Elev=177.88'Storage=5 cf0.09 cfs0.09 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 44HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3: Surface 3[87] Warning: Oscillations may require smaller dt or Finer Routing (severity=482)Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 0.24" for 2-YR eventInflow = 0.02 cfs @ 12.13 hrs, Volume= 50 cfOutflow = 0.01 cfs @ 12.26 hrs, Volume= 50 cf, Atten= 54%, Lag= 7.8 minPrimary = 0.00 cfs @ 12.26 hrs, Volume= 1 cf Routed to Reach P1 : 4" Pipe Under PathSecondary = 0.00 cfs @ 12.26 hrs, Volume= 49 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.80' @ 12.26 hrs Surf.Area= 49 sf Storage= 10 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 14.6 min ( 867.1 - 852.5 )Volume Invert Avail.Storage Storage Description#1 181.50' 22 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 15 0 0182.00 71 22 22Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 181.80'12inch-Dome Grate Capacity Primary OutFlow Max=0.00 cfs @ 12.26 hrs HW=181.80' TW=177.25' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.26 hrs HW=181.80' TW=177.34' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 45HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3: Surface 3InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Inflow Area=2,519 sfPeak Elev=181.80'Storage=10 cf0.02 cfs0.01 cfs0.00 cfs0.00 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 46HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3S: Subsurface 3Inflow = 0.10 cfs @ 12.15 hrs, Volume= 344 cfOutflow = 0.10 cfs @ 12.17 hrs, Volume= 343 cf, Atten= 1%, Lag= 0.7 minPrimary = 0.10 cfs @ 12.17 hrs, Volume= 343 cf Routed to Reach P1 : 4" Pipe Under PathRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.40' @ 12.17 hrs Surf.Area= 71 sf Storage= 7 cfPlug-Flow detention time= 4.7 min calculated for 343 cf (100% of inflow)Center-of-Mass det. time= 3.9 min ( 861.2 - 857.3 )Volume Invert Avail.Storage Storage Description#1 177.17' 66 cfCustom Stage Data (Prismatic) Listed below (Recalc)165 cf Overall - 1 cf Embedded = 164 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'67 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 71 0 0179.50 71 165 165Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.09 cfs @ 12.17 hrs HW=177.40' TW=177.27' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.09 cfs @ 1.58 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 47HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3S: Subsurface 3InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.1050.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Peak Elev=177.40'Storage=7 cf0.10 cfs0.10 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 48HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4: Surface 4Inflow Area = 2,525 sf, 10.02% Impervious, Inflow Depth = 1.44" for 2-YR eventInflow = 0.10 cfs @ 12.13 hrs, Volume= 303 cfOutflow = 0.07 cfs @ 12.19 hrs, Volume= 303 cf, Atten= 29%, Lag= 3.5 minPrimary = 0.06 cfs @ 12.19 hrs, Volume= 70 cf Routed to Pond 5 : Surface 5Secondary = 0.01 cfs @ 12.19 hrs, Volume= 233 cf Routed to Pond 4S : Subsurface 4Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.17' @ 12.19 hrs Surf.Area= 152 sf Storage= 54 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 24.6 min ( 873.5 - 848.9 )Volume Invert Avail.Storage Storage Description#1 182.50' 119 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 14 0 0183.00 114 32 32183.51 229 87 119Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.06 cfs @ 12.19 hrs HW=183.17' TW=182.64' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.06 cfs @ 1.32 fps)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.01 cfs @ 12.19 hrs HW=183.17' TW=178.25' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 49HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4: Surface 4InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.110.1050.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,525 sfPeak Elev=183.17'Storage=54 cf0.10 cfs0.07 cfs0.06 cfs0.01 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 50HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4S: Subsurface 4Inflow = 0.01 cfs @ 12.19 hrs, Volume= 233 cfOutflow = 0.01 cfs @ 12.30 hrs, Volume= 232 cf, Atten= 5%, Lag= 6.3 minPrimary = 0.01 cfs @ 12.30 hrs, Volume= 232 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.25' @ 12.30 hrs Surf.Area= 229 sf Storage= 8 cfPlug-Flow detention time= 18.1 min calculated for 232 cf (100% of inflow)Center-of-Mass det. time= 16.2 min ( 929.2 - 913.0 )Volume Invert Avail.Storage Storage Description#1 178.17' 212 cfCustom Stage Data (Prismatic) Listed below (Recalc)534 cf Overall - 3 cf Embedded = 530 cf x 40.0% Voids#2 178.18' 3 cf4.0" Round Pipe Storage Inside #1L= 36.0'215 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.17 229 0 0180.50 229 534 534Device Routing Invert Outlet Devices#1 Primary 178.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.30 hrs HW=178.25' TW=177.77' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.93 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 51HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4S: Subsurface 4InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=178.25'Storage=8 cf0.01 cfs0.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 52HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5: Surface 5Inflow Area = 2,697 sf, 10.53% Impervious, Inflow Depth = 0.41" for 2-YR eventInflow = 0.06 cfs @ 12.19 hrs, Volume= 92 cfOutflow = 0.06 cfs @ 12.23 hrs, Volume= 92 cf, Atten= 9%, Lag= 2.7 minPrimary = 0.05 cfs @ 12.23 hrs, Volume= 56 cf Routed to Pond 6 : Surface 6Secondary = 0.00 cfs @ 12.23 hrs, Volume= 36 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.66' @ 12.23 hrs Surf.Area= 46 sf Storage= 16 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 13.1 min ( 779.7 - 766.6 )Volume Invert Avail.Storage Storage Description#1 182.00' 36 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 36 10 10183.01 68 27 36Device Routing Invert Outlet Devices#1 Secondary 182.00'4.000 in/hr Exfiltration over Surface area #2 Primary 183.00'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.05 cfs @ 12.23 hrs HW=182.66' TW=182.10' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.05 cfs @ 1.28 fps)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.23 hrs HW=182.66' TW=177.76' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 53HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5: Surface 5InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,697 sfPeak Elev=182.66'Storage=16 cf0.06 cfs0.06 cfs0.05 cfs0.00 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 54HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5S: Subsurface 5Inflow = 0.02 cfs @ 12.28 hrs, Volume= 268 cfOutflow = 0.02 cfs @ 12.30 hrs, Volume= 268 cf, Atten= 0%, Lag= 1.5 minPrimary = 0.02 cfs @ 12.30 hrs, Volume= 268 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.77' @ 12.30 hrs Surf.Area= 68 sf Storage= 3 cfPlug-Flow detention time= 5.4 min calculated for 268 cf (100% of inflow)Center-of-Mass det. time= 4.4 min ( 921.1 - 916.7 )Volume Invert Avail.Storage Storage Description#1 177.67' 63 cfCustom Stage Data (Prismatic) Listed below (Recalc)158 cf Overall - 1 cf Embedded = 157 cf x 40.0% Voids#2 177.68' 1 cf4.0" Round Pipe Storage Inside #1L= 12.0'64 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.67 68 0 0180.00 68 158 158Device Routing Invert Outlet Devices#1 Primary 177.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.30 hrs HW=177.77' TW=177.28' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 0.99 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 55HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5S: Subsurface 5InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=177.77'Storage=3 cf0.02 cfs0.02 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 56HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6: Surface 6Inflow Area = 2,885 sf, 11.82% Impervious, Inflow Depth = 0.34" for 2-YR eventInflow = 0.06 cfs @ 12.23 hrs, Volume= 82 cfOutflow = 0.05 cfs @ 12.29 hrs, Volume= 82 cf, Atten= 13%, Lag= 3.6 minPrimary = 0.04 cfs @ 12.29 hrs, Volume= 44 cf Routed to Pond 7 : Surface 7Secondary = 0.00 cfs @ 12.29 hrs, Volume= 38 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.14' @ 12.29 hrs Surf.Area= 46 sf Storage= 17 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 14.4 min ( 787.6 - 773.1 )Volume Invert Avail.Storage Storage Description#1 181.50' 37 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 2 0 0182.00 40 11 11182.51 63 26 37Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 182.50'9.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.04 cfs @ 12.29 hrs HW=182.14' TW=181.04' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.04 cfs @ 1.22 fps)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.29 hrs HW=182.14' TW=177.28' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 57HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6: Surface 6InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,885 sfPeak Elev=182.14'Storage=17 cf0.06 cfs0.05 cfs0.04 cfs0.00 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 58HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6S: Subsurface 6Inflow = 0.02 cfs @ 12.30 hrs, Volume= 306 cfOutflow = 0.02 cfs @ 12.32 hrs, Volume= 306 cf, Atten= 0%, Lag= 1.3 minPrimary = 0.02 cfs @ 12.32 hrs, Volume= 306 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.28' @ 12.32 hrs Surf.Area= 63 sf Storage= 3 cfPlug-Flow detention time= 4.7 min calculated for 306 cf (100% of inflow)Center-of-Mass det. time= 3.9 min ( 914.4 - 910.5 )Volume Invert Avail.Storage Storage Description#1 177.17' 58 cfCustom Stage Data (Prismatic) Listed below (Recalc)147 cf Overall - 1 cf Embedded = 146 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 13.0'59 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 63 0 0179.50 63 147 147Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.32 hrs HW=177.28' TW=176.37' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 1.05 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 59HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6S: Subsurface 6InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0240.0230.0220.0210.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=177.28'Storage=3 cf0.02 cfs0.02 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 60HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7: Surface 7Inflow Area = 3,343 sf, 13.79% Impervious, Inflow Depth = 0.38" for 2-YR eventInflow = 0.05 cfs @ 12.28 hrs, Volume= 107 cfOutflow = 0.04 cfs @ 12.38 hrs, Volume= 107 cf, Atten= 26%, Lag= 5.9 minPrimary = 0.03 cfs @ 12.38 hrs, Volume= 32 cf Routed to Pond 8 : Surface 8Secondary = 0.01 cfs @ 12.38 hrs, Volume= 75 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.12' @ 12.38 hrs Surf.Area= 71 sf Storage= 31 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 35.8 min ( 835.5 - 799.7 )Volume Invert Avail.Storage Storage Description#1 180.00' 69 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)180.00 2 0 0180.50 18 5 5181.00 58 19 24181.51 117 45 69Device Routing Invert Outlet Devices#1 Secondary 180.00'4.000 in/hr Exfiltration over Surface area #2 Primary 181.50'10.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 181.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 181.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.03 cfs @ 12.38 hrs HW=181.12' TW=179.67' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.03 cfs @ 1.09 fps)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.01 cfs @ 12.38 hrs HW=181.12' TW=176.36' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 61HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7: Surface 7InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=3,343 sfPeak Elev=181.12'Storage=31 cf0.05 cfs0.04 cfs0.03 cfs0.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 62HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7S: Subsurface 7[62] Hint: Exceeded Reach P1 OUTLET depth by 0.16' @ 12.20 hrsInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 3.45" for 2-YR eventInflow = 0.12 cfs @ 12.17 hrs, Volume= 725 cfOutflow = 0.11 cfs @ 12.19 hrs, Volume= 724 cf, Atten= 2%, Lag= 1.1 minPrimary = 0.11 cfs @ 12.19 hrs, Volume= 724 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 176.42' @ 12.19 hrs Surf.Area= 117 sf Storage= 13 cfPlug-Flow detention time= 5.5 min calculated for 724 cf (100% of inflow)Center-of-Mass det. time= 4.6 min ( 889.3 - 884.8 )Volume Invert Avail.Storage Storage Description#1 176.17' 108 cfCustom Stage Data (Prismatic) Listed below (Recalc)273 cf Overall - 2 cf Embedded = 271 cf x 40.0% Voids#2 176.18' 2 cf4.0" Round Pipe Storage Inside #1L= 21.0'110 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)176.17 117 0 0178.50 117 273 273Device Routing Invert Outlet Devices#1 Primary 176.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.11 cfs @ 12.19 hrs HW=176.42' TW=174.92' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.11 cfs @ 1.67 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 63HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7S: Subsurface 7InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,519 sfPeak Elev=176.42'Storage=13 cf0.12 cfs0.11 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 64HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8: Surface 8Inflow Area = 3,973 sf, 13.21% Impervious, Inflow Depth = 0.33" for 2-YR eventInflow = 0.04 cfs @ 12.37 hrs, Volume= 108 cfOutflow = 0.01 cfs @ 12.69 hrs, Volume= 108 cf, Atten= 70%, Lag= 19.0 minPrimary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routed to Reach P2 : 8" PipeSecondary = 0.01 cfs @ 12.69 hrs, Volume= 108 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 179.80' @ 12.69 hrs Surf.Area= 127 sf Storage= 41 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 37.4 min ( 856.7 - 819.2 )Volume Invert Avail.Storage Storage Description#1 179.00' 164 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)179.00 7 0 0179.50 49 14 14179.75 120 21 35180.50 223 129 164Device Routing Invert Outlet Devices#1 Secondary 179.00'4.000 in/hr Exfiltration over Surface area #2 Primary 180.00'12inch-Dome Grate Capacity Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=179.00' TW=174.50' (Dynamic Tailwater)2=12inch-Dome Grate Capacity ( Controls 0.00 cfs)Secondary OutFlow Max=0.01 cfs @ 12.69 hrs HW=179.80' TW=174.85' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 65HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8: Surface 8InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0420.040.0380.0360.0340.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Inflow Area=3,973 sfPeak Elev=179.80'Storage=41 cf0.04 cfs0.01 cfs0.00 cfs 0.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 66HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8S: Subsurface 8Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 3.96" for 2-YR eventInflow = 0.12 cfs @ 12.19 hrs, Volume= 832 cfOutflow = 0.12 cfs @ 12.21 hrs, Volume= 832 cf, Atten= 2%, Lag= 1.2 minPrimary = 0.12 cfs @ 12.21 hrs, Volume= 832 cf Routed to Reach P2 : 8" PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.92' @ 12.21 hrs Surf.Area= 120 sf Storage= 13 cfPlug-Flow detention time= 5.3 min calculated for 832 cf (100% of inflow)Center-of-Mass det. time= 4.4 min ( 889.5 - 885.1 )Volume Invert Avail.Storage Storage Description#1 174.67' 111 cfCustom Stage Data (Prismatic) Listed below (Recalc)280 cf Overall - 2 cf Embedded = 278 cf x 40.0% Voids#2 174.68' 2 cf4.0" Round Pipe Storage Inside #1L= 24.0'113 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.67 120 0 0177.00 120 280 280Device Routing Invert Outlet Devices#1 Primary 174.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.12 cfs @ 12.21 hrs HW=174.92' TW=174.63' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.12 cfs @ 1.68 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 67HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8S: Subsurface 8InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,519 sfPeak Elev=174.92'Storage=13 cf0.12 cfs0.12 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 68HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9: Surface 9Inflow Area = 3,923 sf, 27.20% Impervious, Inflow Depth = 1.66" for 2-YR eventInflow = 0.18 cfs @ 12.13 hrs, Volume= 541 cfOutflow = 0.18 cfs @ 12.14 hrs, Volume= 541 cf, Atten= 0%, Lag= 0.2 minPrimary = 0.17 cfs @ 12.14 hrs, Volume= 340 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.14 hrs, Volume= 201 cf Routed to Pond 9S : Subsurface 9Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.32' @ 12.14 hrs Surf.Area= 54 sf Storage= 9 cfPlug-Flow detention time= 7.9 min calculated for 541 cf (100% of inflow)Center-of-Mass det. time= 7.9 min ( 845.4 - 837.5 )Volume Invert Avail.Storage Storage Description#1 174.00' 86 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.00 1 0 0175.00 170 86 86Device Routing Invert Outlet Devices#1 Primary 174.25'12inch-Dome Grate Capacity #2 Secondary 174.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.17 cfs @ 12.14 hrs HW=174.32' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.17 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=174.32' TW=170.72' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 69HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9: Surface 9InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=3,923 sfPeak Elev=174.32'Storage=9 cf0.18 cfs0.18 cfs0.17 cfs0.01 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 70HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9S: Subsurface 9Inflow = 0.01 cfs @ 12.14 hrs, Volume= 201 cfOutflow = 0.00 cfs @ 12.23 hrs, Volume= 200 cf, Atten= 8%, Lag= 5.9 minPrimary = 0.00 cfs @ 12.23 hrs, Volume= 200 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 170.72' @ 12.23 hrs Surf.Area= 170 sf Storage= 9 cfPlug-Flow detention time= 40.3 min calculated for 200 cf (99% of inflow)Center-of-Mass det. time= 36.6 min ( 1,030.6 - 994.0 )Volume Invert Avail.Storage Storage Description#1 170.67' 395 cfCustom Stage Data (Prismatic) Listed below (Recalc)396 cf Overall - 1 cf Embedded = 395 cf#2 170.68' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'396 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)170.67 170 0 0173.00 170 396 396Device Routing Invert Outlet Devices#1 Primary 170.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 12.23 hrs HW=170.72' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.71 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 71HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9S: Subsurface 9InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Peak Elev=170.72'Storage=9 cf0.01 cfs0.00 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 72HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10: Surface 10Inflow Area = 3,386 sf, 9.57% Impervious, Inflow Depth = 1.44" for 2-YR eventInflow = 0.13 cfs @ 12.13 hrs, Volume= 407 cfOutflow = 0.13 cfs @ 12.14 hrs, Volume= 407 cf, Atten= 1%, Lag= 0.5 minPrimary = 0.12 cfs @ 12.14 hrs, Volume= 143 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.14 hrs, Volume= 264 cf Routed to Pond 10S : Subsurface 10Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.30' @ 12.14 hrs Surf.Area= 113 sf Storage= 27 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 11.7 min ( 860.5 - 848.9 )Volume Invert Avail.Storage Storage Description#1 173.00' 142 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)173.00 68 0 0174.00 215 142 142Device Routing Invert Outlet Devices#1 Primary 173.25'12inch-Dome Grate Capacity #2 Secondary 173.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.12 cfs @ 12.14 hrs HW=173.30' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.12 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=173.30' TW=168.74' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 73HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10: Surface 10InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=3,386 sfPeak Elev=173.30'Storage=27 cf0.13 cfs0.13 cfs0.12 cfs0.01 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 74HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10S: Subsurface 10Inflow = 0.01 cfs @ 12.14 hrs, Volume= 264 cfOutflow = 0.01 cfs @ 12.19 hrs, Volume= 264 cf, Atten= 1%, Lag= 3.2 minPrimary = 0.01 cfs @ 12.19 hrs, Volume= 264 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 168.74' @ 12.19 hrs Surf.Area= 215 sf Storage= 6 cfPlug-Flow detention time= 14.7 min calculated for 264 cf (100% of inflow)Center-of-Mass det. time= 12.9 min ( 939.2 - 926.2 )Volume Invert Avail.Storage Storage Description#1 168.67' 200 cfCustom Stage Data (Prismatic) Listed below (Recalc)501 cf Overall - 2 cf Embedded = 499 cf x 40.0% Voids#2 168.68' 2 cf4.0" Round Pipe Storage Inside #1L= 18.0'201 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)168.67 215 0 0171.00 215 501 501Device Routing Invert Outlet Devices#1 Primary 168.68'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.19 hrs HW=168.74' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.82 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 75HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10S: Subsurface 10InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0110.0110.010.010.0090.0090.0080.0080.0070.0070.0060.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Peak Elev=168.74'Storage=6 cf0.01 cfs0.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 76HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11: Surface 11[87] Warning: Oscillations may require smaller dt or Finer Routing (severity=2)Inflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 1.83" for 2-YR eventInflow = 0.10 cfs @ 12.13 hrs, Volume= 439 cfOutflow = 0.10 cfs @ 12.14 hrs, Volume= 439 cf, Atten= 2%, Lag= 0.7 minPrimary = 0.09 cfs @ 12.14 hrs, Volume= 76 cf Routed to Reach P3 : 4" Outlet PipeSecondary = 0.01 cfs @ 12.14 hrs, Volume= 363 cf Routed to Pond 11S : Subsurface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 185.34' @ 12.14 hrs Surf.Area= 109 sf Storage= 48 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 42.4 min ( 1,077.0 - 1,034.6 )Volume Invert Avail.Storage Storage Description#1 184.50' 284 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)184.50 23 0 0185.00 56 20 20186.00 211 134 153186.50 310 130 284Device Routing Invert Outlet Devices#1 Secondary 184.50'4.000 in/hr Exfiltration over Surface area #2 Primary 185.30'12inch-Dome Grate Capacity Primary OutFlow Max=0.09 cfs @ 12.14 hrs HW=185.34' TW=183.25' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.09 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=185.34' TW=183.24' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 77HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11: Surface 11InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.110.1050.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,880 sfPeak Elev=185.34'Storage=48 cf0.10 cfs0.10 cfs0.09 cfs0.01 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 78HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11S: Subsurface 11[90] Warning: Qout>Qin may require smaller dt or Finer RoutingInflow = 0.01 cfs @ 12.14 hrs, Volume= 363 cfOutflow = 0.01 cfs @ 12.30 hrs, Volume= 363 cf, Atten= 0%, Lag= 9.1 minPrimary = 0.01 cfs @ 12.30 hrs, Volume= 363 cf Routed to Reach P3 : 4" Outlet PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.26' @ 12.21 hrs Surf.Area= 310 sf Storage= 11 cfPlug-Flow detention time= 22.9 min calculated for 363 cf (100% of inflow)Center-of-Mass det. time= 22.3 min ( 1,170.2 - 1,147.9 )Volume Invert Avail.Storage Storage Description#1 183.17' 289 cfCustom Stage Data (Prismatic) Listed below (Recalc)722 cf Overall x 40.0% VoidsElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)183.17 310 0 0185.50 310 722 722Device Routing Invert Outlet Devices#1 Primary 183.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.30 hrs HW=183.25' TW=183.23' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.74 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 79HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11S: Subsurface 11InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=183.26'Storage=11 cf0.01 cfs0.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 80HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 29P: Landscape FilterInflow Area = 5,639 sf,100.00% Impervious, Inflow Depth = 2.85" for 2-YR eventInflow = 0.37 cfs @ 12.13 hrs, Volume= 1,338 cfOutflow = 0.30 cfs @ 12.17 hrs, Volume= 1,333 cf, Atten= 19%, Lag= 2.7 minPrimary = 0.30 cfs @ 12.17 hrs, Volume= 1,333 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 170.87' @ 12.17 hrs Surf.Area= 1,000 sf Storage= 146 cfPlug-Flow detention time= 30.3 min calculated for 1,333 cf (100% of inflow)Center-of-Mass det. time= 28.2 min ( 787.4 - 759.3 )Volume Invert Avail.Storage Storage Description#1 170.50' 1,000 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Voids Inc.Store Cum.Store(feet) (sq-ft) (%) (cubic-feet) (cubic-feet)170.50 1,000 0.0 0 0170.51 1,000 40.0 4 4171.50 1,000 40.0 396 400171.51 1,000 20.0 2 402174.50 1,000 20.0 598 1,000Device Routing Invert Outlet Devices#1 Primary 170.51'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.30 cfs @ 12.17 hrs HW=170.87' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.30 cfs @ 2.03 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 81HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 29P: Landscape FilterInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=5,639 sfPeak Elev=170.87'Storage=146 cf0.37 cfs0.30 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 82HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 30P: Porous PaversInflow Area = 443 sf, 33.86% Impervious, Inflow Depth = 1.73" for 2-YR eventInflow = 0.00 cfs @ 21.71 hrs, Volume= 64 cfOutflow = 0.00 cfs @ 21.74 hrs, Volume= 63 cf, Atten= 0%, Lag= 1.8 minPrimary = 0.00 cfs @ 21.74 hrs, Volume= 63 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.95' @ 21.74 hrs Surf.Area= 150 sf Storage= 2 cfPlug-Flow detention time= 38.5 min calculated for 63 cf (99% of inflow)Center-of-Mass det. time= 27.6 min ( 1,484.1 - 1,456.5 )Volume Invert Avail.Storage Storage Description#1 174.92' 135 cf31" section beneath paver (Prismatic) Listed below (Recalc)387 cf Overall - 2 cf Embedded = 385 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'137 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 150 0 0177.50 150 387 387Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 21.74 hrs HW=174.95' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.52 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 83HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 30P: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0020.0010.0010.0010.0010.0010.0010.0010.0010.0010.0000.0000.0000.00000Inflow Area=443 sfPeak Elev=174.95'Storage=2 cf0.00 cfs0.00 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 84HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 31P: Distribution Pipes[57] Hint: Peaked at 173.72' (Flood elevation advised)Inflow Area = 2,750 sf,100.00% Impervious, Inflow Depth = 2.85" for 2-YR eventInflow = 0.18 cfs @ 12.13 hrs, Volume= 653 cfOutflow = 0.18 cfs @ 12.13 hrs, Volume= 653 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.18 cfs @ 12.13 hrs, Volume= 652 cf Routed to Pond 29P : Landscape FilterSecondary = 0.00 cfs @ 12.13 hrs, Volume= 0 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.72' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'6.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.18 cfs @ 12.13 hrs HW=173.72' TW=170.84' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.18 cfs @ 2.09 fps)Secondary OutFlow Max=0.00 cfs @ 12.13 hrs HW=173.72' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.00 cfs @ 0.53 fps)Pond 31P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,750 sfPeak Elev=173.72'0.18 cfs0.18 cfs0.18 cfs0.00 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 85HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 33P: Distribution Pipes[57] Hint: Peaked at 173.74' (Flood elevation advised)Inflow Area = 2,889 sf,100.00% Impervious, Inflow Depth = 2.85" for 2-YR eventInflow = 0.19 cfs @ 12.13 hrs, Volume= 686 cfOutflow = 0.19 cfs @ 12.13 hrs, Volume= 686 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.19 cfs @ 12.13 hrs, Volume= 685 cf Routed to Pond 29P : Landscape FilterSecondary = 0.00 cfs @ 12.13 hrs, Volume= 1 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.74' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'4.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.19 cfs @ 12.13 hrs HW=173.74' TW=170.84' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.19 cfs @ 2.17 fps)Secondary OutFlow Max=0.00 cfs @ 12.13 hrs HW=173.74' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.00 cfs @ 0.68 fps)Pond 33P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,889 sfPeak Elev=173.74'0.19 cfs0.19 cfs0.19 cfs0.00 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 86HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PN: Porous PaversInflow Area = 676 sf, 77.51% Impervious, Inflow Depth = 2.43" for 2-YR eventInflow = 0.00 cfs @ 20.97 hrs, Volume= 137 cfOutflow = 0.00 cfs @ 21.17 hrs, Volume= 135 cf, Atten= 0%, Lag= 12.2 minPrimary = 0.00 cfs @ 21.17 hrs, Volume= 135 cf Routed to Pond 11 : Surface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 188.47' @ 21.17 hrs Surf.Area= 464 sf Storage= 8 cfPlug-Flow detention time= 78.2 min calculated for 135 cf (99% of inflow)Center-of-Mass det. time= 62.5 min ( 1,478.3 - 1,415.9 )Volume Invert Avail.Storage Storage Description#1 188.42' 417 cf31" section beneath pavers (Prismatic) Listed below (Recalc)1,197 cf Overall - 6 cf Embedded = 1,191 cf x 35.0% Voids#2 188.43' 6 cf4.0" Round Pipe Storage Inside #1L= 67.0'423 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)188.42 464 0 0191.00 464 1,197 1,197Device Routing Invert Outlet Devices#1 Primary 188.43'4.0" Round Culvert L= 7.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 188.43' / 186.00' S= 0.3471 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.09 sf Primary OutFlow Max=0.00 cfs @ 21.17 hrs HW=188.47' TW=184.94' (Dynamic Tailwater)1=Culvert (Inlet Controls 0.00 cfs @ 0.53 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 87HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PN: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0030.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000Inflow Area=676 sfPeak Elev=188.47'Storage=8 cf4.0"Round Culvertn=0.013L=7.0'S=0.3471 '/'0.00 cfs0.00 cfs NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 88HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PS: Porous PaversInflow Area = 2,379 sf, 11.60% Impervious, Inflow Depth = 1.44" for 2-YR eventInflow = 0.01 cfs @ 21.72 hrs, Volume= 286 cfOutflow = 0.01 cfs @ 21.77 hrs, Volume= 285 cf, Atten= 0%, Lag= 3.0 minPrimary = 0.01 cfs @ 21.77 hrs, Volume= 285 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.98' @ 21.77 hrs Surf.Area= 248 sf Storage= 5 cfPlug-Flow detention time= 24.1 min calculated for 285 cf (100% of inflow)Center-of-Mass det. time= 19.5 min ( 1,491.8 - 1,472.2 )Volume Invert Avail.Storage Storage Description#1 174.92' 223 cf31" section beneath paver (Prismatic) Listed below (Recalc)640 cf Overall - 2 cf Embedded = 637 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'226 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 248 0 0177.50 248 640 640Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 21.77 hrs HW=174.98' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.76 fps) NOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 89HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PS: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0070.0070.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Inflow Area=2,379 sfPeak Elev=174.98'Storage=5 cf0.01 cfs0.01 cfsNOAA 24-hr D 2-YR Rainfall=3.08"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 90HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Link 33L: On-site Closed DrainageInflow Area = 27,635 sf, 35.49% Impervious, Inflow Depth = 1.81" for 2-YR eventInflow = 0.86 cfs @ 12.15 hrs, Volume= 4,171 cfPrimary = 0.86 cfs @ 12.15 hrs, Volume= 4,171 cf, Atten= 0%, Lag= 0.0 min Routed to Reach DP-PR : Proposed SitePrimary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsLink 33L: On-site Closed DrainageInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.950.90.850.80.750.70.650.60.550.50.450.40.350.30.250.20.150.10.050Inflow Area=27,635 sf0.86 cfs0.86 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 91HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=1,918 sf 33.52% Impervious Runoff Depth=3.41"Subcatchment PR1: Basin 1 Tc=6.0 min CN=86 Runoff=0.17 cfs 545 cfRunoff Area=3,386 sf 9.57% Impervious Runoff Depth=3.03"Subcatchment PR10: Basin 10 Tc=6.0 min CN=82 Runoff=0.27 cfs 854 cfRunoff Area=2,204 sf 27.72% Impervious Runoff Depth=3.31"Subcatchment PR11: Basin 11 Tc=6.0 min CN=85 Runoff=0.19 cfs 608 cfRunoff Area=2,493 sf 1.36% Impervious Runoff Depth=2.84"Subcatchment PR12: West site to Area Drain Tc=6.0 min CN=80 Runoff=0.19 cfs 590 cfRunoff Area=2,379 sf 11.60% Impervious Runoff Depth=3.03"Subcatchment PR13: Pavers front Tc=674.0 min CN=82 Runoff=0.01 cfs 600 cfRunoff Area=676 sf 77.51% Impervious Runoff Depth=4.25"Subcatchment PR14: Pavers North Tc=674.0 min CN=94 Runoff=0.01 cfs 239 cfRunoff Area=2,750 sf 100.00% Impervious Runoff Depth=4.70"Subcatchment PR15a: Roof West Tc=6.0 min CN=98 Runoff=0.30 cfs 1,078 cfRunoff Area=2,889 sf 100.00% Impervious Runoff Depth=4.70"Subcatchment PR15b: Roof East Tc=6.0 min CN=98 Runoff=0.31 cfs 1,132 cfRunoff Area=13,694 sf 44.87% Impervious Runoff Depth=3.61"Subcatchment PR16: Remainder of site Tc=6.0 min CN=88 Runoff=1.28 cfs 4,122 cfRunoff Area=443 sf 33.86% Impervious Runoff Depth=3.41"Subcatchment PR17: Pavers path Tc=674.0 min CN=86 Runoff=0.00 cfs 126 cfRunoff Area=164 sf 0.00% Impervious Runoff Depth=2.84"Subcatchment PR2: Basin 2 Tc=6.0 min CN=80 Runoff=0.01 cfs 39 cfRunoff Area=437 sf 3.20% Impervious Runoff Depth=2.93"Subcatchment PR3: Basin 3 Tc=6.0 min CN=81 Runoff=0.03 cfs 107 cfRunoff Area=2,525 sf 10.02% Impervious Runoff Depth=3.03"Subcatchment PR4: Basin 4 Tc=6.0 min CN=82 Runoff=0.20 cfs 637 cfRunoff Area=172 sf 18.02% Impervious Runoff Depth=3.12"Subcatchment PR5: Basin 5 Tc=6.0 min CN=83 Runoff=0.01 cfs 45 cfRunoff Area=188 sf 30.32% Impervious Runoff Depth=3.31"Subcatchment PR6: Basin 6 Tc=6.0 min CN=85 Runoff=0.02 cfs 52 cfRunoff Area=458 sf 26.20% Impervious Runoff Depth=3.31"Subcatchment PR7: Basin 7 Tc=6.0 min CN=85 Runoff=0.04 cfs 126 cfNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 92HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCRunoff Area=630 sf 10.16% Impervious Runoff Depth=3.03"Subcatchment PR8: Basin 8 Tc=6.0 min CN=82 Runoff=0.05 cfs 159 cfRunoff Area=3,923 sf 27.20% Impervious Runoff Depth=3.31"Subcatchment PR9: Basin 9 Tc=6.0 min CN=85 Runoff=0.34 cfs 1,083 cf Inflow=2.98 cfs 12,128 cfReach DP-PR: Proposed Site Outflow=2.98 cfs 12,128 cfAvg. Flow Depth=0.13' Max Vel=5.24 fps Inflow=0.21 cfs 690 cfReach P1: 4" Pipe Under Path6.0" Round Pipe n=0.013 L=15.0' S=0.0667 '/' Capacity=1.45 cfs Outflow=0.21 cfs 690 cfAvg. Flow Depth=0.25' Max Vel=3.46 fps Inflow=0.42 cfs 1,706 cfReach P2: 8" Pipe8.0" Round Pipe n=0.013 L=65.0' S=0.0129 '/' Capacity=1.37 cfs Outflow=0.42 cfs 1,706 cfAvg. Flow Depth=0.12' Max Vel=5.27 fps Inflow=0.18 cfs 846 cfReach P3: 4" Outlet Pipe6.0" Round Pipe n=0.013 L=136.0' S=0.0748 '/' Capacity=1.53 cfs Outflow=0.18 cfs 846 cfPeak Elev=183.33' Storage=14 cf Inflow=0.17 cfs 545 cfPond 1: Surface 1 Primary=0.17 cfs 431 cf Secondary=0.00 cfs 114 cf Outflow=0.17 cfs 545 cfPeak Elev=178.21' Storage=1 cf Inflow=0.00 cfs 114 cfPond 1S: Subsurface 1 Outflow=0.00 cfs 114 cfPeak Elev=182.00' Storage=0 cf Inflow=0.18 cfs 470 cfPond 2: Surface 2 Primary=0.00 cfs 0 cf Secondary=0.18 cfs 470 cf Outflow=0.18 cfs 470 cfPeak Elev=178.02' Storage=9 cf Inflow=0.18 cfs 584 cfPond 2S: Subsurface 2 Outflow=0.18 cfs 584 cfPeak Elev=181.81' Storage=10 cf Inflow=0.03 cfs 107 cfPond 3: Surface 3 Primary=0.03 cfs 24 cf Secondary=0.00 cfs 82 cf Outflow=0.03 cfs 107 cfPeak Elev=177.53' Storage=11 cf Inflow=0.18 cfs 666 cfPond 3S: Subsurface 3 Outflow=0.18 cfs 666 cfPeak Elev=183.32' Storage=80 cf Inflow=0.20 cfs 637 cfPond 4: Surface 4 Primary=0.16 cfs 260 cf Secondary=0.02 cfs 377 cf Outflow=0.17 cfs 637 cfPeak Elev=178.26' Storage=9 cf Inflow=0.02 cfs 377 cfPond 4S: Subsurface 4 Outflow=0.02 cfs 376 cfPeak Elev=182.82' Storage=24 cf Inflow=0.17 cfs 305 cfPond 5: Surface 5 Primary=0.16 cfs 244 cf Secondary=0.01 cfs 61 cf Outflow=0.16 cfs 305 cfPeak Elev=177.78' Storage=3 cf Inflow=0.02 cfs 437 cfPond 5S: Subsurface 5 Outflow=0.02 cfs 436 cfPeak Elev=182.33' Storage=26 cf Inflow=0.17 cfs 296 cfPond 6: Surface 6 Primary=0.16 cfs 234 cf Secondary=0.01 cfs 62 cf Outflow=0.17 cfs 296 cf NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 93HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPeak Elev=177.29' Storage=3 cf Inflow=0.03 cfs 498 cfPond 6S: Subsurface 6 Outflow=0.03 cfs 498 cfPeak Elev=181.34' Storage=50 cf Inflow=0.19 cfs 360 cfPond 7: Surface 7 Primary=0.17 cfs 243 cf Secondary=0.01 cfs 117 cf Outflow=0.18 cfs 360 cfPeak Elev=176.65' Storage=24 cf Inflow=0.24 cfs 1,305 cfPond 7S: Subsurface 7 Outflow=0.23 cfs 1,305 cfPeak Elev=180.07' Storage=81 cf Inflow=0.21 cfs 402 cfPond 8: Surface 8 Primary=0.19 cfs 192 cf Secondary=0.02 cfs 210 cf Outflow=0.20 cfs 402 cfPeak Elev=175.17' Storage=25 cf Inflow=0.25 cfs 1,515 cfPond 8S: Subsurface 8 Outflow=0.24 cfs 1,514 cfPeak Elev=174.36' Storage=11 cf Inflow=0.34 cfs 1,083 cfPond 9: Surface 9 Primary=0.34 cfs 833 cf Secondary=0.01 cfs 250 cf Outflow=0.34 cfs 1,083 cfPeak Elev=170.73' Storage=9 cf Inflow=0.01 cfs 250 cfPond 9S: Subsurface 9 Outflow=0.01 cfs 248 cfPeak Elev=173.34' Storage=32 cf Inflow=0.27 cfs 854 cfPond 10: Surface 10 Primary=0.26 cfs 442 cf Secondary=0.01 cfs 412 cf Outflow=0.27 cfs 854 cfPeak Elev=168.74' Storage=6 cf Inflow=0.01 cfs 412 cfPond 10S: Subsurface 10 Outflow=0.01 cfs 411 cfPeak Elev=185.37' Storage=51 cf Inflow=0.19 cfs 846 cfPond 11: Surface 11 Primary=0.18 cfs 267 cf Secondary=0.01 cfs 579 cf Outflow=0.19 cfs 846 cfPeak Elev=183.29' Storage=15 cf Inflow=0.01 cfs 579 cfPond 11S: Subsurface 11 Outflow=0.02 cfs 579 cfPeak Elev=170.96' Storage=182 cf Inflow=0.48 cfs 2,166 cfPond 29P: Landscape Filter Outflow=0.42 cfs 2,162 cfPeak Elev=174.96' Storage=2 cf Inflow=0.00 cfs 126 cfPond 30P: Porous Pavers Outflow=0.00 cfs 125 cfPeak Elev=173.85' Inflow=0.30 cfs 1,078 cfPond 31P: Distribution Pipes Primary=0.23 cfs 1,057 cf Secondary=0.06 cfs 21 cf Outflow=0.30 cfs 1,078 cfPeak Elev=173.88' Inflow=0.31 cfs 1,132 cfPond 33P: Distribution Pipes Primary=0.25 cfs 1,109 cf Secondary=0.07 cfs 23 cf Outflow=0.31 cfs 1,132 cfPeak Elev=188.48' Storage=10 cf Inflow=0.01 cfs 239 cfPond PN: Porous Pavers4.0" Round Culvert n=0.013 L=7.0' S=0.3471 '/' Outflow=0.01 cfs 238 cfPeak Elev=175.00' Storage=8 cf Inflow=0.01 cfs 600 cfPond PS: Porous Pavers Outflow=0.01 cfs 599 cfNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 94HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLC Inflow=1.71 cfs 8,007 cfLink 33L: On-site Closed Drainage Primary=1.71 cfs 8,007 cfTotal Runoff Area = 41,329 sf Runoff Volume = 12,142 cf Average Runoff Depth = 3.53"61.40% Pervious = 25,378 sf 38.60% Impervious = 15,951 sf NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 95HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR1: Basin 1Runoff = 0.17 cfs @ 12.13 hrs, Volume= 545 cf, Depth= 3.41" Routed to Pond 1 : Surface 1Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 643 98 Site Impervious1,275 80 >75% Grass cover, Good, HSG D1,918 86 Weighted Average1,275 66.48% Pervious Area643 33.52% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR1: Basin 1RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=1,918 sfRunoff Volume=545 cfRunoff Depth=3.41"Tc=6.0 minCN=860.17 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 96HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR10: Basin 10Runoff = 0.27 cfs @ 12.13 hrs, Volume= 854 cf, Depth= 3.03" Routed to Pond 10 : Surface 10Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 324 98 Site Impervious3,062 80 >75% Grass cover, Good, HSG D3,386 82 Weighted Average3,062 90.43% Pervious Area324 9.57% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR10: Basin 10RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=3,386 sfRunoff Volume=854 cfRunoff Depth=3.03"Tc=6.0 minCN=820.27 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 97HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR11: Basin 11Runoff = 0.19 cfs @ 12.13 hrs, Volume= 608 cf, Depth= 3.31" Routed to Pond 11 : Surface 11Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 611 98 Site Impervious1,593 80 >75% Grass cover, Good, HSG D2,204 85 Weighted Average1,593 72.28% Pervious Area611 27.72% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR11: Basin 11RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=2,204 sfRunoff Volume=608 cfRunoff Depth=3.31"Tc=6.0 minCN=850.19 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 98HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR12: West site to Area DrainRunoff = 0.19 cfs @ 12.13 hrs, Volume= 590 cf, Depth= 2.84" Routed to Link 33L : On-site Closed DrainageRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 34 98 Site Impervious2,459 80 >75% Grass cover, Good, HSG D2,493 80 Weighted Average2,459 98.64% Pervious Area34 1.36% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR12: West site to Area DrainRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=2,493 sfRunoff Volume=590 cfRunoff Depth=2.84"Tc=6.0 minCN=800.19 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 99HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR13: Pavers frontRunoff = 0.01 cfs @ 21.71 hrs, Volume= 600 cf, Depth= 3.03" Routed to Pond PS : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 28 98 Site Impervious* 248 98 Permeable Pavers2,103 80 >75% Grass cover, Good, HSG D2,379 82 Weighted Average2,103 88.40% Pervious Area276 11.60% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR13: Pavers frontRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=2,379 sfRunoff Volume=600 cfRunoff Depth=3.03"Tc=674.0 minCN=820.01 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 100HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR14: Pavers NorthRunoff = 0.01 cfs @ 20.96 hrs, Volume= 239 cf, Depth= 4.25" Routed to Pond PN : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 60 98 Site Impervious* 464 98 Porous Pavers152 80 >75% Grass cover, Good, HSG D676 94 Weighted Average152 22.49% Pervious Area524 77.51% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Pavers TcSubcatchment PR14: Pavers NorthRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=676 sfRunoff Volume=239 cfRunoff Depth=4.25"Tc=674.0 minCN=940.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 101HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15a: Roof WestRunoff = 0.30 cfs @ 12.13 hrs, Volume= 1,078 cf, Depth= 4.70" Routed to Pond 31P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 2,750 98 Roof2,750 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15a: Roof WestRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=2,750 sfRunoff Volume=1,078 cfRunoff Depth=4.70"Tc=6.0 minCN=980.30 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 102HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15b: Roof EastRunoff = 0.31 cfs @ 12.13 hrs, Volume= 1,132 cf, Depth= 4.70" Routed to Pond 33P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 2,889 98 Roof2,889 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15b: Roof EastRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=2,889 sfRunoff Volume=1,132 cfRunoff Depth=4.70"Tc=6.0 minCN=980.31 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 103HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR16: Remainder of siteRunoff = 1.28 cfs @ 12.13 hrs, Volume= 4,122 cf, Depth= 3.61" Routed to Reach DP-PR : Proposed SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 6,144 98 Site Impervious7,550 80 >75% Grass cover, Good, HSG D13,694 88 Weighted Average7,550 55.13% Pervious Area6,144 44.87% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR16: Remainder of siteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)10NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=13,694 sfRunoff Volume=4,122 cfRunoff Depth=3.61"Tc=6.0 minCN=881.28 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 104HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR17: Pavers pathRunoff = 0.00 cfs @ 20.97 hrs, Volume= 126 cf, Depth= 3.41" Routed to Pond 30P : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 150 98 Permeable Pavers293 80 >75% Grass cover, Good, HSG D443 86 Weighted Average293 66.14% Pervious Area150 33.86% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR17: Pavers pathRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=443 sfRunoff Volume=126 cfRunoff Depth=3.41"Tc=674.0 minCN=860.00 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 105HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR2: Basin 2Runoff = 0.01 cfs @ 12.13 hrs, Volume= 39 cf, Depth= 2.84" Routed to Pond 2 : Surface 2Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description164 80 >75% Grass cover, Good, HSG D164 100.00% Pervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR2: Basin 2RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=164 sfRunoff Volume=39 cfRunoff Depth=2.84"Tc=6.0 minCN=800.01 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 106HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR3: Basin 3Runoff = 0.03 cfs @ 12.13 hrs, Volume= 107 cf, Depth= 2.93" Routed to Pond 3 : Surface 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 14 98 Site Impervious423 80 >75% Grass cover, Good, HSG D437 81 Weighted Average423 96.80% Pervious Area14 3.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR3: Basin 3RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0380.0360.0340.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=437 sfRunoff Volume=107 cfRunoff Depth=2.93"Tc=6.0 minCN=810.03 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 107HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR4: Basin 4Runoff = 0.20 cfs @ 12.13 hrs, Volume= 637 cf, Depth= 3.03" Routed to Pond 4 : Surface 4Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 253 98 Impervious2,272 80 >75% Grass cover, Good, HSG D2,525 82 Weighted Average2,272 89.98% Pervious Area253 10.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR4: Basin 4RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.220.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=2,525 sfRunoff Volume=637 cfRunoff Depth=3.03"Tc=6.0 minCN=820.20 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 108HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR5: Basin 5Runoff = 0.01 cfs @ 12.13 hrs, Volume= 45 cf, Depth= 3.12" Routed to Pond 5 : Surface 5Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 31 98 Site Impervious141 80 >75% Grass cover, Good, HSG D172 83 Weighted Average141 81.98% Pervious Area31 18.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR5: Basin 5RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=172 sfRunoff Volume=45 cfRunoff Depth=3.12"Tc=6.0 minCN=830.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 109HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR6: Basin 6Runoff = 0.02 cfs @ 12.13 hrs, Volume= 52 cf, Depth= 3.31" Routed to Pond 6 : Surface 6Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 57 98 Site Impervious131 80 >75% Grass cover, Good, HSG D188 85 Weighted Average131 69.68% Pervious Area57 30.32% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR6: Basin 6RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=188 sfRunoff Volume=52 cfRunoff Depth=3.31"Tc=6.0 minCN=850.02 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 110HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR7: Basin 7Runoff = 0.04 cfs @ 12.13 hrs, Volume= 126 cf, Depth= 3.31" Routed to Pond 7 : Surface 7Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 120 98 Site Impervious338 80 >75% Grass cover, Good, HSG D458 85 Weighted Average338 73.80% Pervious Area120 26.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR7: Basin 7RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0440.0420.040.0380.0360.0340.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=458 sfRunoff Volume=126 cfRunoff Depth=3.31"Tc=6.0 minCN=850.04 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 111HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR8: Basin 8Runoff = 0.05 cfs @ 12.13 hrs, Volume= 159 cf, Depth= 3.03" Routed to Pond 8 : Surface 8Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 64 98 Site Impervious566 80 >75% Grass cover, Good, HSG D630 82 Weighted Average566 89.84% Pervious Area64 10.16% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR8: Basin 8RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=630 sfRunoff Volume=159 cfRunoff Depth=3.03"Tc=6.0 minCN=820.05 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 112HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR9: Basin 9Runoff = 0.34 cfs @ 12.13 hrs, Volume= 1,083 cf, Depth= 3.31" Routed to Pond 9 : Surface 9Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 10-YR Rainfall=4.94"Area (sf) CN Description* 1,067 98 Impervious2,856 80 >75% Grass cover, Good, HSG D3,923 85 Weighted Average2,856 72.80% Pervious Area1,067 27.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR9: Basin 9RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D10-YR Rainfall=4.94"Runoff Area=3,923 sfRunoff Volume=1,083 cfRunoff Depth=3.31"Tc=6.0 minCN=850.34 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 113HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-PR: Proposed Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,329 sf, 38.60% Impervious, Inflow Depth = 3.52" for 10-YR eventInflow = 2.98 cfs @ 12.14 hrs, Volume= 12,128 cfOutflow = 2.98 cfs @ 12.14 hrs, Volume= 12,128 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-PR: Proposed SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)3210Inflow Area=41,329 sf2.98 cfs2.98 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 114HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P1: 4" Pipe Under Path[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 3.29" for 10-YR eventInflow = 0.21 cfs @ 12.16 hrs, Volume= 690 cfOutflow = 0.21 cfs @ 12.16 hrs, Volume= 690 cf, Atten= 0%, Lag= 0.0 min Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 5.24 fps, Min. Travel Time= 0.0 minAvg. Velocity = 1.75 fps, Avg. Travel Time= 0.1 minPeak Storage= 1 cf @ 12.16 hrsAverage Depth at Peak Storage= 0.13' , Surface Width= 0.44'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.45 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 15.0' Slope= 0.0667 '/'Inlet Invert= 177.18', Outlet Invert= 176.18' NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 115HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P1: 4" Pipe Under PathInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.230.220.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,519 sfAvg. Flow Depth=0.13'Max Vel=5.24 fps6.0"Round Pipen=0.013L=15.0'S=0.0667 '/'Capacity=1.45 cfs0.21 cfs0.21 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 116HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P2: 8" Pipe[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 6,492 sf, 18.21% Impervious, Inflow Depth = 3.15" for 10-YR eventInflow = 0.42 cfs @ 12.22 hrs, Volume= 1,706 cfOutflow = 0.42 cfs @ 12.22 hrs, Volume= 1,706 cf, Atten= 0%, Lag= 0.2 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 3.46 fps, Min. Travel Time= 0.3 minAvg. Velocity = 1.14 fps, Avg. Travel Time= 0.9 minPeak Storage= 8 cf @ 12.22 hrsAverage Depth at Peak Storage= 0.25' , Surface Width= 0.65'Bank-Full Depth= 0.67' Flow Area= 0.3 sf, Capacity= 1.37 cfs8.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 65.0' Slope= 0.0129 '/'Inlet Invert= 174.50', Outlet Invert= 173.66' NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 117HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P2: 8" PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.460.440.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=6,492 sfAvg. Flow Depth=0.25'Max Vel=3.46 fps8.0"Round Pipen=0.013L=65.0'S=0.0129 '/'Capacity=1.37 cfs0.42 cfs0.42 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 118HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P3: 4" Outlet Pipe[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 3.53" for 10-YR eventInflow = 0.18 cfs @ 12.14 hrs, Volume= 846 cfOutflow = 0.18 cfs @ 12.15 hrs, Volume= 846 cf, Atten= 0%, Lag= 0.3 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 5.27 fps, Min. Travel Time= 0.4 minAvg. Velocity = 1.49 fps, Avg. Travel Time= 1.5 minPeak Storage= 5 cf @ 12.15 hrsAverage Depth at Peak Storage= 0.12' , Surface Width= 0.42'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.53 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 136.0' Slope= 0.0748 '/'Inlet Invert= 183.17', Outlet Invert= 173.00' NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 119HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P3: 4" Outlet PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,880 sfAvg. Flow Depth=0.12'Max Vel=5.27 fps6.0"Round Pipen=0.013L=136.0'S=0.0748 '/'Capacity=1.53 cfs0.18 cfs0.18 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 120HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1: Surface 1Inflow Area = 1,918 sf, 33.52% Impervious, Inflow Depth = 3.41" for 10-YR eventInflow = 0.17 cfs @ 12.13 hrs, Volume= 545 cfOutflow = 0.17 cfs @ 12.14 hrs, Volume= 545 cf, Atten= 1%, Lag= 0.7 minPrimary = 0.17 cfs @ 12.14 hrs, Volume= 431 cf Routed to Pond 2 : Surface 2Secondary = 0.00 cfs @ 12.14 hrs, Volume= 114 cf Routed to Pond 1S : Subsurface 1Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.33' @ 12.14 hrs Surf.Area= 42 sf Storage= 14 cfPlug-Flow detention time= 10.0 min calculated for 545 cf (100% of inflow)Center-of-Mass det. time= 10.0 min ( 822.1 - 812.0 )Volume Invert Avail.Storage Storage Description#1 182.50' 23 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 2 0 0183.00 17 5 5183.51 55 18 23Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.17 cfs @ 12.14 hrs HW=183.33' TW=182.00' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.13 cfs @ 2.15 fps)4=Orifice/Grate (Orifice Controls 0.03 cfs @ 0.92 fps)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=183.33' TW=178.21' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 121HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1: Surface 1InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=1,918 sfPeak Elev=183.33'Storage=14 cf0.17 cfs0.17 cfs0.17 cfs0.00 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 122HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1S: Subsurface 1Inflow = 0.00 cfs @ 12.14 hrs, Volume= 114 cfOutflow = 0.00 cfs @ 12.17 hrs, Volume= 114 cf, Atten= 2%, Lag= 1.6 minPrimary = 0.00 cfs @ 12.17 hrs, Volume= 114 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.21' @ 12.17 hrs Surf.Area= 52 sf Storage= 1 cfPlug-Flow detention time= 7.8 min calculated for 114 cf (100% of inflow)Center-of-Mass det. time= 6.8 min ( 955.7 - 948.9 )Volume Invert Avail.Storage Storage Description#1 178.16' 48 cfCustom Stage Data (Prismatic) Listed below (Recalc)122 cf Overall - 1 cf Embedded = 121 cf x 40.0% Voids#2 178.17' 1 cf4.0" Round Pipe Storage Inside #1L= 11.8'49 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.16 52 0 0180.50 52 122 122Device Routing Invert Outlet Devices#1 Primary 178.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 12.17 hrs HW=178.21' TW=178.01' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.67 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 123HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1S: Subsurface 1InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0040.0040.0040.0040.0030.0030.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000Peak Elev=178.21'Storage=1 cf0.00 cfs0.00 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 124HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2: Surface 2Inflow Area = 2,082 sf, 30.88% Impervious, Inflow Depth = 2.71" for 10-YR eventInflow = 0.18 cfs @ 12.14 hrs, Volume= 470 cfOutflow = 0.18 cfs @ 12.14 hrs, Volume= 470 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routed to Pond 3 : Surface 3Secondary = 0.18 cfs @ 12.14 hrs, Volume= 470 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.00' @ 0.00 hrs Surf.Area= 2 sf Storage= 0 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 0.0 min ( 791.9 - 791.9 )Volume Invert Avail.Storage Storage Description#1 182.00' 28 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 25 7 7183.01 60 22 28Device Routing Invert Outlet Devices#1 Secondary 182.00'4.00 cfs Exfiltration at all elevations #2 Primary 183.00'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=182.00' TW=181.50' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate ( Controls 0.00 cfs)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=182.00' TW=178.01' (Dynamic Tailwater)1=Exfiltration (Passes 0.00 cfs of 4.00 cfs potential flow) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 125HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2: Surface 2InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,082 sfPeak Elev=182.00'Storage=0 cf0.18 cfs0.18 cfs0.00 cfs0.18 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 126HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2S: Subsurface 2Inflow = 0.18 cfs @ 12.14 hrs, Volume= 584 cfOutflow = 0.18 cfs @ 12.15 hrs, Volume= 584 cf, Atten= 1%, Lag= 0.7 minPrimary = 0.18 cfs @ 12.15 hrs, Volume= 584 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.02' @ 12.15 hrs Surf.Area= 57 sf Storage= 9 cfPlug-Flow detention time= 2.8 min calculated for 584 cf (100% of inflow)Center-of-Mass det. time= 2.5 min ( 826.5 - 824.0 )Volume Invert Avail.Storage Storage Description#1 177.66' 53 cfCustom Stage Data (Prismatic) Listed below (Recalc)133 cf Overall - 1 cf Embedded = 133 cf x 40.0% Voids#2 177.67' 1 cf4.0" Round Pipe Storage Inside #1L= 10.0'54 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.66 57 0 0180.00 57 133 133Device Routing Invert Outlet Devices#1 Primary 177.67'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.18 cfs @ 12.15 hrs HW=178.02' TW=177.53' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.18 cfs @ 2.05 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 127HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2S: Subsurface 2InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Peak Elev=178.02'Storage=9 cf0.18 cfs0.18 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 128HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3: Surface 3Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 0.51" for 10-YR eventInflow = 0.03 cfs @ 12.13 hrs, Volume= 107 cfOutflow = 0.03 cfs @ 12.14 hrs, Volume= 107 cf, Atten= 0%, Lag= 0.4 minPrimary = 0.03 cfs @ 12.14 hrs, Volume= 24 cf Routed to Reach P1 : 4" Pipe Under PathSecondary = 0.00 cfs @ 12.14 hrs, Volume= 82 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.81' @ 12.14 hrs Surf.Area= 50 sf Storage= 10 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 12.7 min ( 841.1 - 828.4 )Volume Invert Avail.Storage Storage Description#1 181.50' 22 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 15 0 0182.00 71 22 22Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 181.80'12inch-Dome Grate Capacity Primary OutFlow Max=0.03 cfs @ 12.14 hrs HW=181.81' TW=177.31' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.03 cfs)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=181.81' TW=177.51' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 129HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3: Surface 3InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0380.0360.0340.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Inflow Area=2,519 sfPeak Elev=181.81'Storage=10 cf0.03 cfs0.03 cfs0.03 cfs0.00 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 130HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3S: Subsurface 3Inflow = 0.18 cfs @ 12.15 hrs, Volume= 666 cfOutflow = 0.18 cfs @ 12.17 hrs, Volume= 666 cf, Atten= 2%, Lag= 0.8 minPrimary = 0.18 cfs @ 12.17 hrs, Volume= 666 cf Routed to Reach P1 : 4" Pipe Under PathRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.53' @ 12.17 hrs Surf.Area= 71 sf Storage= 11 cfPlug-Flow detention time= 3.3 min calculated for 666 cf (100% of inflow)Center-of-Mass det. time= 3.0 min ( 835.2 - 832.2 )Volume Invert Avail.Storage Storage Description#1 177.17' 66 cfCustom Stage Data (Prismatic) Listed below (Recalc)165 cf Overall - 1 cf Embedded = 164 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'67 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 71 0 0179.50 71 165 165Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.18 cfs @ 12.17 hrs HW=177.53' TW=177.31' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.18 cfs @ 2.07 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 131HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3S: Subsurface 3InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Peak Elev=177.53'Storage=11 cf0.18 cfs0.18 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 132HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4: Surface 4Inflow Area = 2,525 sf, 10.02% Impervious, Inflow Depth = 3.03" for 10-YR eventInflow = 0.20 cfs @ 12.13 hrs, Volume= 637 cfOutflow = 0.17 cfs @ 12.17 hrs, Volume= 637 cf, Atten= 15%, Lag= 2.3 minPrimary = 0.16 cfs @ 12.17 hrs, Volume= 260 cf Routed to Pond 5 : Surface 5Secondary = 0.02 cfs @ 12.17 hrs, Volume= 377 cf Routed to Pond 4S : Subsurface 4Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.32' @ 12.17 hrs Surf.Area= 186 sf Storage= 80 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 22.9 min ( 848.2 - 825.3 )Volume Invert Avail.Storage Storage Description#1 182.50' 119 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 14 0 0183.00 114 32 32183.51 229 87 119Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.16 cfs @ 12.17 hrs HW=183.32' TW=182.82' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.13 cfs @ 2.09 fps)4=Orifice/Grate (Orifice Controls 0.03 cfs @ 0.85 fps)Secondary OutFlow Max=0.02 cfs @ 12.17 hrs HW=183.32' TW=178.26' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.02 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 133HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4: Surface 4InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.220.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,525 sfPeak Elev=183.32'Storage=80 cf0.20 cfs0.17 cfs0.16 cfs0.02 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 134HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4S: Subsurface 4Inflow = 0.02 cfs @ 12.17 hrs, Volume= 377 cfOutflow = 0.02 cfs @ 12.23 hrs, Volume= 376 cf, Atten= 4%, Lag= 3.7 minPrimary = 0.02 cfs @ 12.23 hrs, Volume= 376 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.26' @ 12.23 hrs Surf.Area= 229 sf Storage= 9 cfPlug-Flow detention time= 15.4 min calculated for 376 cf (100% of inflow)Center-of-Mass det. time= 13.9 min ( 934.9 - 920.9 )Volume Invert Avail.Storage Storage Description#1 178.17' 212 cfCustom Stage Data (Prismatic) Listed below (Recalc)534 cf Overall - 3 cf Embedded = 530 cf x 40.0% Voids#2 178.18' 3 cf4.0" Round Pipe Storage Inside #1L= 36.0'215 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.17 229 0 0180.50 229 534 534Device Routing Invert Outlet Devices#1 Primary 178.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.23 hrs HW=178.26' TW=177.78' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 0.98 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 135HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4S: Subsurface 4InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=178.26'Storage=9 cf0.02 cfs0.02 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 136HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5: Surface 5Inflow Area = 2,697 sf, 10.53% Impervious, Inflow Depth = 1.36" for 10-YR eventInflow = 0.17 cfs @ 12.17 hrs, Volume= 305 cfOutflow = 0.16 cfs @ 12.18 hrs, Volume= 305 cf, Atten= 2%, Lag= 1.0 minPrimary = 0.16 cfs @ 12.18 hrs, Volume= 244 cf Routed to Pond 6 : Surface 6Secondary = 0.01 cfs @ 12.18 hrs, Volume= 61 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.82' @ 12.18 hrs Surf.Area= 56 sf Storage= 24 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 7.8 min ( 762.3 - 754.5 )Volume Invert Avail.Storage Storage Description#1 182.00' 36 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 36 10 10183.01 68 27 36Device Routing Invert Outlet Devices#1 Secondary 182.00'4.000 in/hr Exfiltration over Surface area #2 Primary 183.00'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.16 cfs @ 12.18 hrs HW=182.82' TW=182.33' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.13 cfs @ 2.11 fps)4=Orifice/Grate (Orifice Controls 0.03 cfs @ 0.88 fps)Secondary OutFlow Max=0.01 cfs @ 12.18 hrs HW=182.82' TW=177.77' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 137HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5: Surface 5InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,697 sfPeak Elev=182.82'Storage=24 cf0.17 cfs0.16 cfs0.16 cfs0.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 138HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5S: Subsurface 5Inflow = 0.02 cfs @ 12.22 hrs, Volume= 437 cfOutflow = 0.02 cfs @ 12.24 hrs, Volume= 436 cf, Atten= 0%, Lag= 1.3 minPrimary = 0.02 cfs @ 12.24 hrs, Volume= 436 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.78' @ 12.24 hrs Surf.Area= 68 sf Storage= 3 cfPlug-Flow detention time= 4.3 min calculated for 436 cf (100% of inflow)Center-of-Mass det. time= 3.8 min ( 925.8 - 922.0 )Volume Invert Avail.Storage Storage Description#1 177.67' 63 cfCustom Stage Data (Prismatic) Listed below (Recalc)158 cf Overall - 1 cf Embedded = 157 cf x 40.0% Voids#2 177.68' 1 cf4.0" Round Pipe Storage Inside #1L= 12.0'64 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.67 68 0 0180.00 68 158 158Device Routing Invert Outlet Devices#1 Primary 177.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.24 hrs HW=177.78' TW=177.29' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 1.05 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 139HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5S: Subsurface 5InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0240.0230.0220.0210.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=177.78'Storage=3 cf0.02 cfs0.02 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 140HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6: Surface 6Inflow Area = 2,885 sf, 11.82% Impervious, Inflow Depth = 1.23" for 10-YR eventInflow = 0.17 cfs @ 12.18 hrs, Volume= 296 cfOutflow = 0.17 cfs @ 12.20 hrs, Volume= 296 cf, Atten= 2%, Lag= 1.0 minPrimary = 0.16 cfs @ 12.20 hrs, Volume= 234 cf Routed to Pond 7 : Surface 7Secondary = 0.01 cfs @ 12.20 hrs, Volume= 62 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.33' @ 12.20 hrs Surf.Area= 55 sf Storage= 26 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 7.7 min ( 762.8 - 755.0 )Volume Invert Avail.Storage Storage Description#1 181.50' 37 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 2 0 0182.00 40 11 11182.51 63 26 37Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 182.50'9.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.16 cfs @ 12.20 hrs HW=182.33' TW=181.34' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.13 cfs @ 2.14 fps)4=Orifice/Grate (Orifice Controls 0.03 cfs @ 0.90 fps)Secondary OutFlow Max=0.01 cfs @ 12.20 hrs HW=182.33' TW=177.29' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 141HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6: Surface 6InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,885 sfPeak Elev=182.33'Storage=26 cf0.17 cfs0.17 cfs0.16 cfs0.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 142HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6S: Subsurface 6Inflow = 0.03 cfs @ 12.23 hrs, Volume= 498 cfOutflow = 0.03 cfs @ 12.25 hrs, Volume= 498 cf, Atten= 0%, Lag= 1.1 minPrimary = 0.03 cfs @ 12.25 hrs, Volume= 498 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.29' @ 12.25 hrs Surf.Area= 63 sf Storage= 3 cfPlug-Flow detention time= 4.1 min calculated for 498 cf (100% of inflow)Center-of-Mass det. time= 3.3 min ( 918.5 - 915.2 )Volume Invert Avail.Storage Storage Description#1 177.17' 58 cfCustom Stage Data (Prismatic) Listed below (Recalc)147 cf Overall - 1 cf Embedded = 146 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 13.0'59 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 63 0 0179.50 63 147 147Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.03 cfs @ 12.25 hrs HW=177.29' TW=176.55' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.03 cfs @ 1.11 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 143HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6S: Subsurface 6InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Peak Elev=177.29'Storage=3 cf0.03 cfs0.03 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 144HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7: Surface 7Inflow Area = 3,343 sf, 13.79% Impervious, Inflow Depth = 1.29" for 10-YR eventInflow = 0.19 cfs @ 12.18 hrs, Volume= 360 cfOutflow = 0.18 cfs @ 12.21 hrs, Volume= 360 cf, Atten= 5%, Lag= 1.8 minPrimary = 0.17 cfs @ 12.21 hrs, Volume= 243 cf Routed to Pond 8 : Surface 8Secondary = 0.01 cfs @ 12.21 hrs, Volume= 117 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.34' @ 12.21 hrs Surf.Area= 97 sf Storage= 50 cfPlug-Flow detention time= 18.5 min calculated for 360 cf (100% of inflow)Center-of-Mass det. time= 18.5 min ( 786.6 - 768.1 )Volume Invert Avail.Storage Storage Description#1 180.00' 69 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)180.00 2 0 0180.50 18 5 5181.00 58 19 24181.51 117 45 69Device Routing Invert Outlet Devices#1 Secondary 180.00'4.000 in/hr Exfiltration over Surface area #2 Primary 181.50'10.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 181.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 181.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.17 cfs @ 12.21 hrs HW=181.34' TW=180.07' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.14 cfs @ 2.20 fps)4=Orifice/Grate (Orifice Controls 0.04 cfs @ 0.97 fps)Secondary OutFlow Max=0.01 cfs @ 12.21 hrs HW=181.34' TW=176.63' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 145HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7: Surface 7InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=3,343 sfPeak Elev=181.34'Storage=50 cf0.19 cfs0.18 cfs0.17 cfs0.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 146HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7S: Subsurface 7[62] Hint: Exceeded Reach P1 OUTLET depth by 0.35' @ 12.19 hrsInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 6.22" for 10-YR eventInflow = 0.24 cfs @ 12.16 hrs, Volume= 1,305 cfOutflow = 0.23 cfs @ 12.19 hrs, Volume= 1,305 cf, Atten= 4%, Lag= 1.5 minPrimary = 0.23 cfs @ 12.19 hrs, Volume= 1,305 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 176.65' @ 12.19 hrs Surf.Area= 117 sf Storage= 24 cfPlug-Flow detention time= 4.0 min calculated for 1,305 cf (100% of inflow)Center-of-Mass det. time= 3.7 min ( 872.4 - 868.7 )Volume Invert Avail.Storage Storage Description#1 176.17' 108 cfCustom Stage Data (Prismatic) Listed below (Recalc)273 cf Overall - 2 cf Embedded = 271 cf x 40.0% Voids#2 176.18' 2 cf4.0" Round Pipe Storage Inside #1L= 21.0'110 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)176.17 117 0 0178.50 117 273 273Device Routing Invert Outlet Devices#1 Primary 176.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.23 cfs @ 12.19 hrs HW=176.65' TW=175.15' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.23 cfs @ 2.65 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 147HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7S: Subsurface 7InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfPeak Elev=176.65'Storage=24 cf0.24 cfs0.23 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 148HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8: Surface 8Inflow Area = 3,973 sf, 13.21% Impervious, Inflow Depth = 1.21" for 10-YR eventInflow = 0.21 cfs @ 12.20 hrs, Volume= 402 cfOutflow = 0.20 cfs @ 12.22 hrs, Volume= 402 cf, Atten= 2%, Lag= 1.5 minPrimary = 0.19 cfs @ 12.22 hrs, Volume= 192 cf Routed to Reach P2 : 8" PipeSecondary = 0.02 cfs @ 12.22 hrs, Volume= 210 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 180.07' @ 12.22 hrs Surf.Area= 164 sf Storage= 81 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 28.4 min ( 804.4 - 776.0 )Volume Invert Avail.Storage Storage Description#1 179.00' 164 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)179.00 7 0 0179.50 49 14 14179.75 120 21 35180.50 223 129 164Device Routing Invert Outlet Devices#1 Secondary 179.00'4.000 in/hr Exfiltration over Surface area #2 Primary 180.00'12inch-Dome Grate Capacity Primary OutFlow Max=0.19 cfs @ 12.22 hrs HW=180.07' TW=174.75' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.19 cfs)Secondary OutFlow Max=0.02 cfs @ 12.22 hrs HW=180.07' TW=175.16' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.02 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 149HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8: Surface 8InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.220.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=3,973 sfPeak Elev=180.07'Storage=81 cf0.21 cfs0.20 cfs0.19 cfs0.02 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 150HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8S: Subsurface 8Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 7.22" for 10-YR eventInflow = 0.25 cfs @ 12.19 hrs, Volume= 1,515 cfOutflow = 0.24 cfs @ 12.22 hrs, Volume= 1,514 cf, Atten= 4%, Lag= 1.6 minPrimary = 0.24 cfs @ 12.22 hrs, Volume= 1,514 cf Routed to Reach P2 : 8" PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 175.17' @ 12.22 hrs Surf.Area= 120 sf Storage= 25 cfPlug-Flow detention time= 3.8 min calculated for 1,514 cf (100% of inflow)Center-of-Mass det. time= 3.5 min ( 874.2 - 870.7 )Volume Invert Avail.Storage Storage Description#1 174.67' 111 cfCustom Stage Data (Prismatic) Listed below (Recalc)280 cf Overall - 2 cf Embedded = 278 cf x 40.0% Voids#2 174.68' 2 cf4.0" Round Pipe Storage Inside #1L= 24.0'113 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.67 120 0 0177.00 120 280 280Device Routing Invert Outlet Devices#1 Primary 174.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.24 cfs @ 12.22 hrs HW=175.16' TW=174.75' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.24 cfs @ 2.71 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 151HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8S: Subsurface 8InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfPeak Elev=175.17'Storage=25 cf0.25 cfs0.24 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 152HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9: Surface 9Inflow Area = 3,923 sf, 27.20% Impervious, Inflow Depth = 3.31" for 10-YR eventInflow = 0.34 cfs @ 12.13 hrs, Volume= 1,083 cfOutflow = 0.34 cfs @ 12.13 hrs, Volume= 1,083 cf, Atten= 0%, Lag= 0.2 minPrimary = 0.34 cfs @ 12.13 hrs, Volume= 833 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.13 hrs, Volume= 250 cf Routed to Pond 9S : Subsurface 9Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.36' @ 12.13 hrs Surf.Area= 61 sf Storage= 11 cfPlug-Flow detention time= 5.2 min calculated for 1,083 cf (100% of inflow)Center-of-Mass det. time= 5.2 min ( 820.7 - 815.5 )Volume Invert Avail.Storage Storage Description#1 174.00' 86 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.00 1 0 0175.00 170 86 86Device Routing Invert Outlet Devices#1 Primary 174.25'12inch-Dome Grate Capacity #2 Secondary 174.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.34 cfs @ 12.13 hrs HW=174.36' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.34 cfs)Secondary OutFlow Max=0.01 cfs @ 12.13 hrs HW=174.36' TW=170.72' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 153HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9: Surface 9InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=3,923 sfPeak Elev=174.36'Storage=11 cf0.34 cfs0.34 cfs0.34 cfs0.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 154HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9S: Subsurface 9Inflow = 0.01 cfs @ 12.13 hrs, Volume= 250 cfOutflow = 0.01 cfs @ 12.22 hrs, Volume= 248 cf, Atten= 10%, Lag= 5.2 minPrimary = 0.01 cfs @ 12.22 hrs, Volume= 248 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 170.73' @ 12.22 hrs Surf.Area= 170 sf Storage= 9 cfPlug-Flow detention time= 38.2 min calculated for 248 cf (99% of inflow)Center-of-Mass det. time= 34.9 min ( 989.7 - 954.7 )Volume Invert Avail.Storage Storage Description#1 170.67' 395 cfCustom Stage Data (Prismatic) Listed below (Recalc)396 cf Overall - 1 cf Embedded = 395 cf#2 170.68' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'396 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)170.67 170 0 0173.00 170 396 396Device Routing Invert Outlet Devices#1 Primary 170.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.22 hrs HW=170.73' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.72 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 155HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9S: Subsurface 9InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Peak Elev=170.73'Storage=9 cf0.01 cfs0.01 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 156HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10: Surface 10Inflow Area = 3,386 sf, 9.57% Impervious, Inflow Depth = 3.03" for 10-YR eventInflow = 0.27 cfs @ 12.13 hrs, Volume= 854 cfOutflow = 0.27 cfs @ 12.14 hrs, Volume= 854 cf, Atten= 1%, Lag= 0.5 minPrimary = 0.26 cfs @ 12.14 hrs, Volume= 442 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.14 hrs, Volume= 412 cf Routed to Pond 10S : Subsurface 10Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.34' @ 12.14 hrs Surf.Area= 118 sf Storage= 32 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 11.0 min ( 836.3 - 825.3 )Volume Invert Avail.Storage Storage Description#1 173.00' 142 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)173.00 68 0 0174.00 215 142 142Device Routing Invert Outlet Devices#1 Primary 173.25'12inch-Dome Grate Capacity #2 Secondary 173.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.26 cfs @ 12.14 hrs HW=173.34' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.26 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=173.34' TW=168.74' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 157HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10: Surface 10InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=3,386 sfPeak Elev=173.34'Storage=32 cf0.27 cfs0.27 cfs0.26 cfs0.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 158HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10S: Subsurface 10Inflow = 0.01 cfs @ 12.14 hrs, Volume= 412 cfOutflow = 0.01 cfs @ 12.18 hrs, Volume= 411 cf, Atten= 1%, Lag= 2.5 minPrimary = 0.01 cfs @ 12.18 hrs, Volume= 411 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 168.74' @ 12.18 hrs Surf.Area= 215 sf Storage= 6 cfPlug-Flow detention time= 12.2 min calculated for 411 cf (100% of inflow)Center-of-Mass det. time= 11.3 min ( 948.2 - 936.9 )Volume Invert Avail.Storage Storage Description#1 168.67' 200 cfCustom Stage Data (Prismatic) Listed below (Recalc)501 cf Overall - 2 cf Embedded = 499 cf x 40.0% Voids#2 168.68' 2 cf4.0" Round Pipe Storage Inside #1L= 18.0'201 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)168.67 215 0 0171.00 215 501 501Device Routing Invert Outlet Devices#1 Primary 168.68'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.18 hrs HW=168.74' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.83 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 159HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10S: Subsurface 10InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0120.0110.0110.010.010.0090.0090.0080.0080.0070.0070.0060.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Peak Elev=168.74'Storage=6 cf0.01 cfs0.01 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 160HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11: Surface 11Inflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 3.53" for 10-YR eventInflow = 0.19 cfs @ 12.13 hrs, Volume= 846 cfOutflow = 0.19 cfs @ 12.14 hrs, Volume= 846 cf, Atten= 1%, Lag= 0.5 minPrimary = 0.18 cfs @ 12.14 hrs, Volume= 267 cf Routed to Reach P3 : 4" Outlet PipeSecondary = 0.01 cfs @ 12.14 hrs, Volume= 579 cf Routed to Pond 11S : Subsurface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 185.37' @ 12.14 hrs Surf.Area= 113 sf Storage= 51 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 41.8 min ( 1,034.6 - 992.8 )Volume Invert Avail.Storage Storage Description#1 184.50' 284 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)184.50 23 0 0185.00 56 20 20186.00 211 134 153186.50 310 130 284Device Routing Invert Outlet Devices#1 Secondary 184.50'4.000 in/hr Exfiltration over Surface area #2 Primary 185.30'12inch-Dome Grate Capacity Primary OutFlow Max=0.18 cfs @ 12.14 hrs HW=185.37' TW=183.29' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.18 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=185.37' TW=183.29' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 161HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11: Surface 11InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010Inflow Area=2,880 sfPeak Elev=185.37'Storage=51 cf0.19 cfs0.19 cfs0.18 cfs0.01 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 162HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11S: Subsurface 11[90] Warning: Qout>Qin may require smaller dt or Finer RoutingInflow = 0.01 cfs @ 12.14 hrs, Volume= 579 cfOutflow = 0.02 cfs @ 12.22 hrs, Volume= 579 cf, Atten= 0%, Lag= 5.1 minPrimary = 0.02 cfs @ 12.22 hrs, Volume= 579 cf Routed to Reach P3 : 4" Outlet PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.29' @ 12.17 hrs Surf.Area= 310 sf Storage= 15 cfPlug-Flow detention time= 19.2 min calculated for 579 cf (100% of inflow)Center-of-Mass det. time= 18.8 min ( 1,189.7 - 1,170.9 )Volume Invert Avail.Storage Storage Description#1 183.17' 289 cfCustom Stage Data (Prismatic) Listed below (Recalc)722 cf Overall x 40.0% VoidsElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)183.17 310 0 0185.50 310 722 722Device Routing Invert Outlet Devices#1 Primary 183.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.22 hrs HW=183.28' TW=183.27' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 0.64 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 163HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11S: Subsurface 11InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=183.29'Storage=15 cf0.01 cfs0.02 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 164HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 29P: Landscape FilterInflow Area = 5,639 sf,100.00% Impervious, Inflow Depth = 4.61" for 10-YR eventInflow = 0.48 cfs @ 12.13 hrs, Volume= 2,166 cfOutflow = 0.42 cfs @ 12.18 hrs, Volume= 2,162 cf, Atten= 12%, Lag= 3.1 minPrimary = 0.42 cfs @ 12.18 hrs, Volume= 2,162 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 170.96' @ 12.18 hrs Surf.Area= 1,000 sf Storage= 182 cfPlug-Flow detention time= 23.8 min calculated for 2,162 cf (100% of inflow)Center-of-Mass det. time= 22.4 min ( 772.4 - 750.0 )Volume Invert Avail.Storage Storage Description#1 170.50' 1,000 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Voids Inc.Store Cum.Store(feet) (sq-ft) (%) (cubic-feet) (cubic-feet)170.50 1,000 0.0 0 0170.51 1,000 40.0 4 4171.50 1,000 40.0 396 400171.51 1,000 20.0 2 402174.50 1,000 20.0 598 1,000Device Routing Invert Outlet Devices#1 Primary 170.51'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.42 cfs @ 12.18 hrs HW=170.96' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.42 cfs @ 2.27 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 165HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 29P: Landscape FilterInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.50.450.40.350.30.250.20.150.10.050Inflow Area=5,639 sfPeak Elev=170.96'Storage=182 cf0.48 cfs0.42 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 166HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 30P: Porous PaversInflow Area = 443 sf, 33.86% Impervious, Inflow Depth = 3.41" for 10-YR eventInflow = 0.00 cfs @ 20.97 hrs, Volume= 126 cfOutflow = 0.00 cfs @ 21.10 hrs, Volume= 125 cf, Atten= 0%, Lag= 7.7 minPrimary = 0.00 cfs @ 21.10 hrs, Volume= 125 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.96' @ 21.10 hrs Surf.Area= 150 sf Storage= 2 cfPlug-Flow detention time= 25.4 min calculated for 125 cf (100% of inflow)Center-of-Mass det. time= 19.2 min ( 1,453.7 - 1,434.6 )Volume Invert Avail.Storage Storage Description#1 174.92' 135 cf31" section beneath paver (Prismatic) Listed below (Recalc)387 cf Overall - 2 cf Embedded = 385 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'137 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 150 0 0177.50 150 387 387Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 21.10 hrs HW=174.96' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.62 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 167HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 30P: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000Inflow Area=443 sfPeak Elev=174.96'Storage=2 cf0.00 cfs0.00 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 168HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 31P: Distribution Pipes[57] Hint: Peaked at 173.85' (Flood elevation advised)Inflow Area = 2,750 sf,100.00% Impervious, Inflow Depth = 4.70" for 10-YR eventInflow = 0.30 cfs @ 12.13 hrs, Volume= 1,078 cfOutflow = 0.30 cfs @ 12.13 hrs, Volume= 1,078 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.23 cfs @ 12.13 hrs, Volume= 1,057 cf Routed to Pond 29P : Landscape FilterSecondary = 0.06 cfs @ 12.13 hrs, Volume= 21 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.85' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'6.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.23 cfs @ 12.13 hrs HW=173.85' TW=170.93' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.23 cfs @ 2.68 fps)Secondary OutFlow Max=0.06 cfs @ 12.13 hrs HW=173.85' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.06 cfs @ 1.31 fps)Pond 31P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,750 sfPeak Elev=173.85'0.30 cfs0.30 cfs0.23 cfs0.06 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 169HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 33P: Distribution Pipes[57] Hint: Peaked at 173.88' (Flood elevation advised)Inflow Area = 2,889 sf,100.00% Impervious, Inflow Depth = 4.70" for 10-YR eventInflow = 0.31 cfs @ 12.13 hrs, Volume= 1,132 cfOutflow = 0.31 cfs @ 12.13 hrs, Volume= 1,132 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.25 cfs @ 12.13 hrs, Volume= 1,109 cf Routed to Pond 29P : Landscape FilterSecondary = 0.07 cfs @ 12.13 hrs, Volume= 23 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.88' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'4.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.25 cfs @ 12.13 hrs HW=173.88' TW=170.93' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.25 cfs @ 2.81 fps)Secondary OutFlow Max=0.07 cfs @ 12.13 hrs HW=173.88' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.07 cfs @ 1.43 fps)Pond 33P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,889 sfPeak Elev=173.88'0.31 cfs0.31 cfs0.25 cfs0.07 cfs NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 170HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PN: Porous PaversInflow Area = 676 sf, 77.51% Impervious, Inflow Depth = 4.25" for 10-YR eventInflow = 0.01 cfs @ 20.96 hrs, Volume= 239 cfOutflow = 0.01 cfs @ 21.00 hrs, Volume= 238 cf, Atten= 0%, Lag= 2.4 minPrimary = 0.01 cfs @ 21.00 hrs, Volume= 238 cf Routed to Pond 11 : Surface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 188.48' @ 21.00 hrs Surf.Area= 464 sf Storage= 10 cfPlug-Flow detention time= 56.7 min calculated for 238 cf (99% of inflow)Center-of-Mass det. time= 47.2 min ( 1,446.7 - 1,399.5 )Volume Invert Avail.Storage Storage Description#1 188.42' 417 cf31" section beneath pavers (Prismatic) Listed below (Recalc)1,197 cf Overall - 6 cf Embedded = 1,191 cf x 35.0% Voids#2 188.43' 6 cf4.0" Round Pipe Storage Inside #1L= 67.0'423 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)188.42 464 0 0191.00 464 1,197 1,197Device Routing Invert Outlet Devices#1 Primary 188.43'4.0" Round Culvert L= 7.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 188.43' / 186.00' S= 0.3471 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.09 sf Primary OutFlow Max=0.01 cfs @ 21.00 hrs HW=188.48' TW=185.23' (Dynamic Tailwater)1=Culvert (Inlet Controls 0.01 cfs @ 0.61 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 171HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PN: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Inflow Area=676 sfPeak Elev=188.48'Storage=10 cf4.0"Round Culvertn=0.013L=7.0'S=0.3471 '/'0.01 cfs0.01 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 172HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PS: Porous PaversInflow Area = 2,379 sf, 11.60% Impervious, Inflow Depth = 3.03" for 10-YR eventInflow = 0.01 cfs @ 21.71 hrs, Volume= 600 cfOutflow = 0.01 cfs @ 21.72 hrs, Volume= 599 cf, Atten= 0%, Lag= 0.7 minPrimary = 0.01 cfs @ 21.72 hrs, Volume= 599 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 175.00' @ 21.72 hrs Surf.Area= 248 sf Storage= 8 cfPlug-Flow detention time= 15.8 min calculated for 599 cf (100% of inflow)Center-of-Mass det. time= 13.4 min ( 1,461.5 - 1,448.1 )Volume Invert Avail.Storage Storage Description#1 174.92' 223 cf31" section beneath paver (Prismatic) Listed below (Recalc)640 cf Overall - 2 cf Embedded = 637 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'226 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 248 0 0177.50 248 640 640Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 21.72 hrs HW=175.00' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.92 fps) NOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 173HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PS: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Inflow Area=2,379 sfPeak Elev=175.00'Storage=8 cf0.01 cfs0.01 cfsNOAA 24-hr D 10-YR Rainfall=4.94"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 174HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Link 33L: On-site Closed DrainageInflow Area = 27,635 sf, 35.49% Impervious, Inflow Depth = 3.48" for 10-YR eventInflow = 1.71 cfs @ 12.14 hrs, Volume= 8,007 cfPrimary = 1.71 cfs @ 12.14 hrs, Volume= 8,007 cf, Atten= 0%, Lag= 0.0 min Routed to Reach DP-PR : Proposed SitePrimary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsLink 33L: On-site Closed DrainageInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)10Inflow Area=27,635 sf1.71 cfs1.71 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 175HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=1,918 sf 33.52% Impervious Runoff Depth=4.50"Subcatchment PR1: Basin 1 Tc=6.0 min CN=86 Runoff=0.22 cfs 720 cfRunoff Area=3,386 sf 9.57% Impervious Runoff Depth=4.08"Subcatchment PR10: Basin 10 Tc=6.0 min CN=82 Runoff=0.37 cfs 1,151 cfRunoff Area=2,204 sf 27.72% Impervious Runoff Depth=4.40"Subcatchment PR11: Basin 11 Tc=6.0 min CN=85 Runoff=0.25 cfs 808 cfRunoff Area=2,493 sf 1.36% Impervious Runoff Depth=3.87"Subcatchment PR12: West site to Area Drain Tc=6.0 min CN=80 Runoff=0.26 cfs 804 cfRunoff Area=2,379 sf 11.60% Impervious Runoff Depth=4.08"Subcatchment PR13: Pavers front Tc=674.0 min CN=82 Runoff=0.02 cfs 809 cfRunoff Area=676 sf 77.51% Impervious Runoff Depth=5.40"Subcatchment PR14: Pavers North Tc=674.0 min CN=94 Runoff=0.01 cfs 304 cfRunoff Area=2,750 sf 100.00% Impervious Runoff Depth=5.86"Subcatchment PR15a: Roof West Tc=6.0 min CN=98 Runoff=0.37 cfs 1,343 cfRunoff Area=2,889 sf 100.00% Impervious Runoff Depth=5.86"Subcatchment PR15b: Roof East Tc=6.0 min CN=98 Runoff=0.39 cfs 1,411 cfRunoff Area=13,694 sf 44.87% Impervious Runoff Depth=4.72"Subcatchment PR16: Remainder of site Tc=6.0 min CN=88 Runoff=1.65 cfs 5,389 cfRunoff Area=443 sf 33.86% Impervious Runoff Depth=4.50"Subcatchment PR17: Pavers path Tc=674.0 min CN=86 Runoff=0.00 cfs 166 cfRunoff Area=164 sf 0.00% Impervious Runoff Depth=3.87"Subcatchment PR2: Basin 2 Tc=6.0 min CN=80 Runoff=0.02 cfs 53 cfRunoff Area=437 sf 3.20% Impervious Runoff Depth=3.97"Subcatchment PR3: Basin 3 Tc=6.0 min CN=81 Runoff=0.05 cfs 145 cfRunoff Area=2,525 sf 10.02% Impervious Runoff Depth=4.08"Subcatchment PR4: Basin 4 Tc=6.0 min CN=82 Runoff=0.27 cfs 858 cfRunoff Area=172 sf 18.02% Impervious Runoff Depth=4.18"Subcatchment PR5: Basin 5 Tc=6.0 min CN=83 Runoff=0.02 cfs 60 cfRunoff Area=188 sf 30.32% Impervious Runoff Depth=4.40"Subcatchment PR6: Basin 6 Tc=6.0 min CN=85 Runoff=0.02 cfs 69 cfRunoff Area=458 sf 26.20% Impervious Runoff Depth=4.40"Subcatchment PR7: Basin 7 Tc=6.0 min CN=85 Runoff=0.05 cfs 168 cfNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 176HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCRunoff Area=630 sf 10.16% Impervious Runoff Depth=4.08"Subcatchment PR8: Basin 8 Tc=6.0 min CN=82 Runoff=0.07 cfs 214 cfRunoff Area=3,923 sf 27.20% Impervious Runoff Depth=4.40"Subcatchment PR9: Basin 9 Tc=6.0 min CN=85 Runoff=0.45 cfs 1,437 cf Inflow=4.09 cfs 15,896 cfReach DP-PR: Proposed Site Outflow=4.09 cfs 15,896 cfAvg. Flow Depth=0.15' Max Vel=5.64 fps Inflow=0.27 cfs 917 cfReach P1: 4" Pipe Under Path6.0" Round Pipe n=0.013 L=15.0' S=0.0667 '/' Capacity=1.45 cfs Outflow=0.27 cfs 917 cfAvg. Flow Depth=0.30' Max Vel=3.75 fps Inflow=0.57 cfs 2,284 cfReach P2: 8" Pipe8.0" Round Pipe n=0.013 L=65.0' S=0.0129 '/' Capacity=1.37 cfs Outflow=0.57 cfs 2,284 cfAvg. Flow Depth=0.13' Max Vel=5.69 fps Inflow=0.24 cfs 1,110 cfReach P3: 4" Outlet Pipe6.0" Round Pipe n=0.013 L=136.0' S=0.0748 '/' Capacity=1.53 cfs Outflow=0.24 cfs 1,110 cfPeak Elev=183.38' Storage=17 cf Inflow=0.22 cfs 720 cfPond 1: Surface 1 Primary=0.22 cfs 596 cf Secondary=0.00 cfs 124 cf Outflow=0.22 cfs 720 cfPeak Elev=178.21' Storage=1 cf Inflow=0.00 cfs 124 cfPond 1S: Subsurface 1 Outflow=0.00 cfs 124 cfPeak Elev=182.00' Storage=0 cf Inflow=0.23 cfs 649 cfPond 2: Surface 2 Primary=0.00 cfs 0 cf Secondary=0.23 cfs 649 cf Outflow=0.23 cfs 649 cfPeak Elev=178.14' Storage=12 cf Inflow=0.24 cfs 773 cfPond 2S: Subsurface 2 Outflow=0.23 cfs 772 cfPeak Elev=181.82' Storage=10 cf Inflow=0.05 cfs 145 cfPond 3: Surface 3 Primary=0.04 cfs 43 cf Secondary=0.00 cfs 101 cf Outflow=0.05 cfs 145 cfPeak Elev=177.65' Storage=15 cf Inflow=0.24 cfs 874 cfPond 3S: Subsurface 3 Outflow=0.23 cfs 873 cfPeak Elev=183.39' Storage=93 cf Inflow=0.27 cfs 858 cfPond 4: Surface 4 Primary=0.22 cfs 404 cf Secondary=0.02 cfs 455 cf Outflow=0.24 cfs 858 cfPeak Elev=178.27' Storage=9 cf Inflow=0.02 cfs 455 cfPond 4S: Subsurface 4 Outflow=0.02 cfs 454 cfPeak Elev=182.89' Storage=28 cf Inflow=0.24 cfs 464 cfPond 5: Surface 5 Primary=0.23 cfs 386 cf Secondary=0.01 cfs 77 cf Outflow=0.23 cfs 464 cfPeak Elev=177.78' Storage=3 cf Inflow=0.02 cfs 531 cfPond 5S: Subsurface 5 Outflow=0.02 cfs 531 cfPeak Elev=182.40' Storage=30 cf Inflow=0.24 cfs 455 cfPond 6: Surface 6 Primary=0.23 cfs 378 cf Secondary=0.01 cfs 77 cf Outflow=0.24 cfs 455 cf NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 177HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPeak Elev=177.29' Storage=3 cf Inflow=0.03 cfs 608 cfPond 6S: Subsurface 6 Outflow=0.03 cfs 608 cfPeak Elev=181.42' Storage=58 cf Inflow=0.27 cfs 546 cfPond 7: Surface 7 Primary=0.25 cfs 403 cf Secondary=0.01 cfs 143 cf Outflow=0.26 cfs 546 cfPeak Elev=176.82' Storage=31 cf Inflow=0.31 cfs 1,667 cfPond 7S: Subsurface 7 Outflow=0.29 cfs 1,667 cfPeak Elev=180.10' Storage=85 cf Inflow=0.30 cfs 617 cfPond 8: Surface 8 Primary=0.28 cfs 368 cf Secondary=0.02 cfs 249 cf Outflow=0.30 cfs 617 cfPeak Elev=175.33' Storage=33 cf Inflow=0.30 cfs 1,916 cfPond 8S: Subsurface 8 Outflow=0.29 cfs 1,916 cfPeak Elev=174.38' Storage=12 cf Inflow=0.45 cfs 1,437 cfPond 9: Surface 9 Primary=0.44 cfs 1,170 cf Secondary=0.01 cfs 267 cf Outflow=0.45 cfs 1,437 cfPeak Elev=170.73' Storage=10 cf Inflow=0.01 cfs 267 cfPond 9S: Subsurface 9 Outflow=0.01 cfs 265 cfPeak Elev=173.36' Storage=34 cf Inflow=0.37 cfs 1,151 cfPond 10: Surface 10 Primary=0.35 cfs 668 cf Secondary=0.01 cfs 483 cf Outflow=0.36 cfs 1,151 cfPeak Elev=168.74' Storage=6 cf Inflow=0.01 cfs 483 cfPond 10S: Subsurface 10 Outflow=0.01 cfs 482 cfPeak Elev=185.38' Storage=53 cf Inflow=0.25 cfs 1,110 cfPond 11: Surface 11 Primary=0.24 cfs 439 cf Secondary=0.01 cfs 671 cf Outflow=0.25 cfs 1,110 cfPeak Elev=183.31' Storage=17 cf Inflow=0.01 cfs 671 cfPond 11S: Subsurface 11 Outflow=0.02 cfs 671 cfPeak Elev=170.99' Storage=198 cf Inflow=0.52 cfs 2,658 cfPond 29P: Landscape Filter Outflow=0.46 cfs 2,653 cfPeak Elev=174.97' Storage=3 cf Inflow=0.00 cfs 166 cfPond 30P: Porous Pavers Outflow=0.00 cfs 166 cfPeak Elev=173.90' Inflow=0.37 cfs 1,343 cfPond 31P: Distribution Pipes Primary=0.25 cfs 1,297 cf Secondary=0.11 cfs 47 cf Outflow=0.37 cfs 1,343 cfPeak Elev=173.95' Inflow=0.39 cfs 1,411 cfPond 33P: Distribution Pipes Primary=0.27 cfs 1,361 cf Secondary=0.12 cfs 50 cf Outflow=0.39 cfs 1,411 cfPeak Elev=188.49' Storage=11 cf Inflow=0.01 cfs 304 cfPond PN: Porous Pavers4.0" Round Culvert n=0.013 L=7.0' S=0.3471 '/' Outflow=0.01 cfs 302 cfPeak Elev=175.02' Storage=9 cf Inflow=0.02 cfs 809 cfPond PS: Porous Pavers Outflow=0.02 cfs 808 cfNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 178HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLC Inflow=2.45 cfs 10,508 cfLink 33L: On-site Closed Drainage Primary=2.45 cfs 10,508 cfTotal Runoff Area = 41,329 sf Runoff Volume = 15,909 cf Average Runoff Depth = 4.62"61.40% Pervious = 25,378 sf 38.60% Impervious = 15,951 sf NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 179HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR1: Basin 1Runoff = 0.22 cfs @ 12.13 hrs, Volume= 720 cf, Depth= 4.50" Routed to Pond 1 : Surface 1Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 643 98 Site Impervious1,275 80 >75% Grass cover, Good, HSG D1,918 86 Weighted Average1,275 66.48% Pervious Area643 33.52% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR1: Basin 1RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.250.240.230.220.210.20.190.180.170.160.150.140.130.120.110.10.090.080.070.060.050.040.030.020.010NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=1,918 sfRunoff Volume=720 cfRunoff Depth=4.50"Tc=6.0 minCN=860.22 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 180HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR10: Basin 10Runoff = 0.37 cfs @ 12.13 hrs, Volume= 1,151 cf, Depth= 4.08" Routed to Pond 10 : Surface 10Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 324 98 Site Impervious3,062 80 >75% Grass cover, Good, HSG D3,386 82 Weighted Average3,062 90.43% Pervious Area324 9.57% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR10: Basin 10RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=3,386 sfRunoff Volume=1,151 cfRunoff Depth=4.08"Tc=6.0 minCN=820.37 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 181HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR11: Basin 11Runoff = 0.25 cfs @ 12.13 hrs, Volume= 808 cf, Depth= 4.40" Routed to Pond 11 : Surface 11Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 611 98 Site Impervious1,593 80 >75% Grass cover, Good, HSG D2,204 85 Weighted Average1,593 72.28% Pervious Area611 27.72% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR11: Basin 11RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=2,204 sfRunoff Volume=808 cfRunoff Depth=4.40"Tc=6.0 minCN=850.25 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 182HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR12: West site to Area DrainRunoff = 0.26 cfs @ 12.13 hrs, Volume= 804 cf, Depth= 3.87" Routed to Link 33L : On-site Closed DrainageRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 34 98 Site Impervious2,459 80 >75% Grass cover, Good, HSG D2,493 80 Weighted Average2,459 98.64% Pervious Area34 1.36% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR12: West site to Area DrainRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=2,493 sfRunoff Volume=804 cfRunoff Depth=3.87"Tc=6.0 minCN=800.26 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 183HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR13: Pavers frontRunoff = 0.02 cfs @ 20.97 hrs, Volume= 809 cf, Depth= 4.08" Routed to Pond PS : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 28 98 Site Impervious* 248 98 Permeable Pavers2,103 80 >75% Grass cover, Good, HSG D2,379 82 Weighted Average2,103 88.40% Pervious Area276 11.60% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR13: Pavers frontRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=2,379 sfRunoff Volume=809 cfRunoff Depth=4.08"Tc=674.0 minCN=820.02 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 184HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR14: Pavers NorthRunoff = 0.01 cfs @ 20.23 hrs, Volume= 304 cf, Depth= 5.40" Routed to Pond PN : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 60 98 Site Impervious* 464 98 Porous Pavers152 80 >75% Grass cover, Good, HSG D676 94 Weighted Average152 22.49% Pervious Area524 77.51% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Pavers TcSubcatchment PR14: Pavers NorthRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0070.0070.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=676 sfRunoff Volume=304 cfRunoff Depth=5.40"Tc=674.0 minCN=940.01 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 185HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15a: Roof WestRunoff = 0.37 cfs @ 12.13 hrs, Volume= 1,343 cf, Depth= 5.86" Routed to Pond 31P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 2,750 98 Roof2,750 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15a: Roof WestRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=2,750 sfRunoff Volume=1,343 cfRunoff Depth=5.86"Tc=6.0 minCN=980.37 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 186HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15b: Roof EastRunoff = 0.39 cfs @ 12.13 hrs, Volume= 1,411 cf, Depth= 5.86" Routed to Pond 33P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 2,889 98 Roof2,889 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15b: Roof EastRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=2,889 sfRunoff Volume=1,411 cfRunoff Depth=5.86"Tc=6.0 minCN=980.39 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 187HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR16: Remainder of siteRunoff = 1.65 cfs @ 12.13 hrs, Volume= 5,389 cf, Depth= 4.72" Routed to Reach DP-PR : Proposed SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 6,144 98 Site Impervious7,550 80 >75% Grass cover, Good, HSG D13,694 88 Weighted Average7,550 55.13% Pervious Area6,144 44.87% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR16: Remainder of siteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)10NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=13,694 sfRunoff Volume=5,389 cfRunoff Depth=4.72"Tc=6.0 minCN=881.65 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 188HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR17: Pavers pathRunoff = 0.00 cfs @ 20.97 hrs, Volume= 166 cf, Depth= 4.50" Routed to Pond 30P : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 150 98 Permeable Pavers293 80 >75% Grass cover, Good, HSG D443 86 Weighted Average293 66.14% Pervious Area150 33.86% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR17: Pavers pathRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0040.0040.0040.0030.0030.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=443 sfRunoff Volume=166 cfRunoff Depth=4.50"Tc=674.0 minCN=860.00 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 189HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR2: Basin 2Runoff = 0.02 cfs @ 12.13 hrs, Volume= 53 cf, Depth= 3.87" Routed to Pond 2 : Surface 2Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description164 80 >75% Grass cover, Good, HSG D164 100.00% Pervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR2: Basin 2RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=164 sfRunoff Volume=53 cfRunoff Depth=3.87"Tc=6.0 minCN=800.02 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 190HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR3: Basin 3Runoff = 0.05 cfs @ 12.13 hrs, Volume= 145 cf, Depth= 3.97" Routed to Pond 3 : Surface 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 14 98 Site Impervious423 80 >75% Grass cover, Good, HSG D437 81 Weighted Average423 96.80% Pervious Area14 3.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR3: Basin 3RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.050.0480.0460.0440.0420.040.0380.0360.0340.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=437 sfRunoff Volume=145 cfRunoff Depth=3.97"Tc=6.0 minCN=810.05 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 191HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR4: Basin 4Runoff = 0.27 cfs @ 12.13 hrs, Volume= 858 cf, Depth= 4.08" Routed to Pond 4 : Surface 4Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 253 98 Impervious2,272 80 >75% Grass cover, Good, HSG D2,525 82 Weighted Average2,272 89.98% Pervious Area253 10.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR4: Basin 4RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=2,525 sfRunoff Volume=858 cfRunoff Depth=4.08"Tc=6.0 minCN=820.27 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 192HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR5: Basin 5Runoff = 0.02 cfs @ 12.13 hrs, Volume= 60 cf, Depth= 4.18" Routed to Pond 5 : Surface 5Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 31 98 Site Impervious141 80 >75% Grass cover, Good, HSG D172 83 Weighted Average141 81.98% Pervious Area31 18.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR5: Basin 5RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0210.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=172 sfRunoff Volume=60 cfRunoff Depth=4.18"Tc=6.0 minCN=830.02 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 193HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR6: Basin 6Runoff = 0.02 cfs @ 12.13 hrs, Volume= 69 cf, Depth= 4.40" Routed to Pond 6 : Surface 6Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 57 98 Site Impervious131 80 >75% Grass cover, Good, HSG D188 85 Weighted Average131 69.68% Pervious Area57 30.32% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR6: Basin 6RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0240.0230.0220.0210.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=188 sfRunoff Volume=69 cfRunoff Depth=4.40"Tc=6.0 minCN=850.02 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 194HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR7: Basin 7Runoff = 0.05 cfs @ 12.13 hrs, Volume= 168 cf, Depth= 4.40" Routed to Pond 7 : Surface 7Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 120 98 Site Impervious338 80 >75% Grass cover, Good, HSG D458 85 Weighted Average338 73.80% Pervious Area120 26.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR7: Basin 7RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=458 sfRunoff Volume=168 cfRunoff Depth=4.40"Tc=6.0 minCN=850.05 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 195HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR8: Basin 8Runoff = 0.07 cfs @ 12.13 hrs, Volume= 214 cf, Depth= 4.08" Routed to Pond 8 : Surface 8Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 64 98 Site Impervious566 80 >75% Grass cover, Good, HSG D630 82 Weighted Average566 89.84% Pervious Area64 10.16% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR8: Basin 8RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=630 sfRunoff Volume=214 cfRunoff Depth=4.08"Tc=6.0 minCN=820.07 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 196HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR9: Basin 9Runoff = 0.45 cfs @ 12.13 hrs, Volume= 1,437 cf, Depth= 4.40" Routed to Pond 9 : Surface 9Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 25-YR Rainfall=6.10"Area (sf) CN Description* 1,067 98 Impervious2,856 80 >75% Grass cover, Good, HSG D3,923 85 Weighted Average2,856 72.80% Pervious Area1,067 27.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR9: Basin 9RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.50.480.460.440.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D25-YR Rainfall=6.10"Runoff Area=3,923 sfRunoff Volume=1,437 cfRunoff Depth=4.40"Tc=6.0 minCN=850.45 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 197HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-PR: Proposed Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,329 sf, 38.60% Impervious, Inflow Depth = 4.62" for 25-YR eventInflow = 4.09 cfs @ 12.14 hrs, Volume= 15,896 cfOutflow = 4.09 cfs @ 12.14 hrs, Volume= 15,896 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-PR: Proposed SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)43210Inflow Area=41,329 sf4.09 cfs4.09 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 198HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P1: 4" Pipe Under Path[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 4.37" for 25-YR eventInflow = 0.27 cfs @ 12.16 hrs, Volume= 917 cfOutflow = 0.27 cfs @ 12.16 hrs, Volume= 917 cf, Atten= 0%, Lag= 0.0 min Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 5.64 fps, Min. Travel Time= 0.0 minAvg. Velocity = 1.87 fps, Avg. Travel Time= 0.1 minPeak Storage= 1 cf @ 12.16 hrsAverage Depth at Peak Storage= 0.15' , Surface Width= 0.45'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.45 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 15.0' Slope= 0.0667 '/'Inlet Invert= 177.18', Outlet Invert= 176.18' NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 199HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P1: 4" Pipe Under PathInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfAvg. Flow Depth=0.15'Max Vel=5.64 fps6.0"Round Pipen=0.013L=15.0'S=0.0667 '/'Capacity=1.45 cfs0.27 cfs0.27 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 200HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P2: 8" Pipe[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 6,492 sf, 18.21% Impervious, Inflow Depth = 4.22" for 25-YR eventInflow = 0.57 cfs @ 12.21 hrs, Volume= 2,284 cfOutflow = 0.57 cfs @ 12.21 hrs, Volume= 2,284 cf, Atten= 0%, Lag= 0.2 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 3.75 fps, Min. Travel Time= 0.3 minAvg. Velocity = 1.22 fps, Avg. Travel Time= 0.9 minPeak Storage= 10 cf @ 12.21 hrsAverage Depth at Peak Storage= 0.30' , Surface Width= 0.66'Bank-Full Depth= 0.67' Flow Area= 0.3 sf, Capacity= 1.37 cfs8.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 65.0' Slope= 0.0129 '/'Inlet Invert= 174.50', Outlet Invert= 173.66' NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 201HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P2: 8" PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.60.550.50.450.40.350.30.250.20.150.10.050Inflow Area=6,492 sfAvg. Flow Depth=0.30'Max Vel=3.75 fps8.0"Round Pipen=0.013L=65.0'S=0.0129 '/'Capacity=1.37 cfs0.57 cfs0.57 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 202HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P3: 4" Outlet Pipe[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 4.62" for 25-YR eventInflow = 0.24 cfs @ 12.15 hrs, Volume= 1,110 cfOutflow = 0.24 cfs @ 12.15 hrs, Volume= 1,110 cf, Atten= 0%, Lag= 0.1 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 5.69 fps, Min. Travel Time= 0.4 minAvg. Velocity = 1.57 fps, Avg. Travel Time= 1.4 minPeak Storage= 6 cf @ 12.15 hrsAverage Depth at Peak Storage= 0.13' , Surface Width= 0.44'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.53 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 136.0' Slope= 0.0748 '/'Inlet Invert= 183.17', Outlet Invert= 173.00' NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 203HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P3: 4" Outlet PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,880 sfAvg. Flow Depth=0.13'Max Vel=5.69 fps6.0"Round Pipen=0.013L=136.0'S=0.0748 '/'Capacity=1.53 cfs0.24 cfs0.24 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 204HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1: Surface 1Inflow Area = 1,918 sf, 33.52% Impervious, Inflow Depth = 4.50" for 25-YR eventInflow = 0.22 cfs @ 12.13 hrs, Volume= 720 cfOutflow = 0.22 cfs @ 12.14 hrs, Volume= 720 cf, Atten= 1%, Lag= 0.6 minPrimary = 0.22 cfs @ 12.14 hrs, Volume= 596 cf Routed to Pond 2 : Surface 2Secondary = 0.00 cfs @ 12.14 hrs, Volume= 124 cf Routed to Pond 1S : Subsurface 1Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.38' @ 12.14 hrs Surf.Area= 46 sf Storage= 17 cfPlug-Flow detention time= 8.3 min calculated for 720 cf (100% of inflow)Center-of-Mass det. time= 8.3 min ( 811.7 - 803.4 )Volume Invert Avail.Storage Storage Description#1 182.50' 23 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 2 0 0183.00 17 5 5183.51 55 18 23Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.22 cfs @ 12.14 hrs HW=183.38' TW=182.00' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.15 cfs @ 2.42 fps)4=Orifice/Grate (Orifice Controls 0.07 cfs @ 1.17 fps)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=183.38' TW=178.21' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 205HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1: Surface 1InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=1,918 sfPeak Elev=183.38'Storage=17 cf0.22 cfs0.22 cfs0.22 cfs0.00 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 206HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1S: Subsurface 1Inflow = 0.00 cfs @ 12.14 hrs, Volume= 124 cfOutflow = 0.00 cfs @ 12.17 hrs, Volume= 124 cf, Atten= 2%, Lag= 1.5 minPrimary = 0.00 cfs @ 12.17 hrs, Volume= 124 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.21' @ 12.17 hrs Surf.Area= 52 sf Storage= 1 cfPlug-Flow detention time= 7.8 min calculated for 124 cf (100% of inflow)Center-of-Mass det. time= 6.6 min ( 926.9 - 920.3 )Volume Invert Avail.Storage Storage Description#1 178.16' 48 cfCustom Stage Data (Prismatic) Listed below (Recalc)122 cf Overall - 1 cf Embedded = 121 cf x 40.0% Voids#2 178.17' 1 cf4.0" Round Pipe Storage Inside #1L= 11.8'49 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.16 52 0 0180.50 52 122 122Device Routing Invert Outlet Devices#1 Primary 178.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 12.17 hrs HW=178.21' TW=178.14' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.68 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 207HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1S: Subsurface 1InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0050.0040.0040.0040.0040.0040.0030.0030.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000Peak Elev=178.21'Storage=1 cf0.00 cfs0.00 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 208HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2: Surface 2Inflow Area = 2,082 sf, 30.88% Impervious, Inflow Depth = 3.74" for 25-YR eventInflow = 0.23 cfs @ 12.14 hrs, Volume= 649 cfOutflow = 0.23 cfs @ 12.14 hrs, Volume= 649 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routed to Pond 3 : Surface 3Secondary = 0.23 cfs @ 12.14 hrs, Volume= 649 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.00' @ 0.00 hrs Surf.Area= 2 sf Storage= 0 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 0.0 min ( 791.7 - 791.7 )Volume Invert Avail.Storage Storage Description#1 182.00' 28 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 25 7 7183.01 60 22 28Device Routing Invert Outlet Devices#1 Secondary 182.00'4.00 cfs Exfiltration at all elevations #2 Primary 183.00'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=182.00' TW=181.50' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate ( Controls 0.00 cfs)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=182.00' TW=178.13' (Dynamic Tailwater)1=Exfiltration (Passes 0.00 cfs of 4.00 cfs potential flow) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 209HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2: Surface 2InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,082 sfPeak Elev=182.00'Storage=0 cf0.23 cfs0.23 cfs0.00 cfs0.23 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 210HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2S: Subsurface 2Inflow = 0.24 cfs @ 12.14 hrs, Volume= 773 cfOutflow = 0.23 cfs @ 12.15 hrs, Volume= 772 cf, Atten= 2%, Lag= 0.8 minPrimary = 0.23 cfs @ 12.15 hrs, Volume= 772 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.14' @ 12.15 hrs Surf.Area= 57 sf Storage= 12 cfPlug-Flow detention time= 2.4 min calculated for 772 cf (100% of inflow)Center-of-Mass det. time= 2.2 min ( 815.6 - 813.4 )Volume Invert Avail.Storage Storage Description#1 177.66' 53 cfCustom Stage Data (Prismatic) Listed below (Recalc)133 cf Overall - 1 cf Embedded = 133 cf x 40.0% Voids#2 177.67' 1 cf4.0" Round Pipe Storage Inside #1L= 10.0'54 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.66 57 0 0180.00 57 133 133Device Routing Invert Outlet Devices#1 Primary 177.67'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.23 cfs @ 12.15 hrs HW=178.14' TW=177.64' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.23 cfs @ 2.66 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 211HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2S: Subsurface 2InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Peak Elev=178.14'Storage=12 cf0.24 cfs0.23 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 212HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3: Surface 3Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 0.69" for 25-YR eventInflow = 0.05 cfs @ 12.13 hrs, Volume= 145 cfOutflow = 0.05 cfs @ 12.14 hrs, Volume= 145 cf, Atten= 0%, Lag= 0.4 minPrimary = 0.04 cfs @ 12.14 hrs, Volume= 43 cf Routed to Reach P1 : 4" Pipe Under PathSecondary = 0.00 cfs @ 12.14 hrs, Volume= 101 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.82' @ 12.14 hrs Surf.Area= 51 sf Storage= 10 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 12.2 min ( 830.9 - 818.7 )Volume Invert Avail.Storage Storage Description#1 181.50' 22 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 15 0 0182.00 71 22 22Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 181.80'12inch-Dome Grate Capacity Primary OutFlow Max=0.04 cfs @ 12.14 hrs HW=181.82' TW=177.32' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.04 cfs)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=181.82' TW=177.61' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 213HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3: Surface 3InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,519 sfPeak Elev=181.82'Storage=10 cf0.05 cfs0.05 cfs0.04 cfs0.00 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 214HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3S: Subsurface 3Inflow = 0.24 cfs @ 12.15 hrs, Volume= 874 cfOutflow = 0.23 cfs @ 12.17 hrs, Volume= 873 cf, Atten= 2%, Lag= 1.0 minPrimary = 0.23 cfs @ 12.17 hrs, Volume= 873 cf Routed to Reach P1 : 4" Pipe Under PathRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.65' @ 12.17 hrs Surf.Area= 71 sf Storage= 15 cfPlug-Flow detention time= 2.9 min calculated for 873 cf (100% of inflow)Center-of-Mass det. time= 2.7 min ( 824.9 - 822.3 )Volume Invert Avail.Storage Storage Description#1 177.17' 66 cfCustom Stage Data (Prismatic) Listed below (Recalc)165 cf Overall - 1 cf Embedded = 164 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'67 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 71 0 0179.50 71 165 165Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.23 cfs @ 12.17 hrs HW=177.65' TW=177.33' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.23 cfs @ 2.65 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 215HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3S: Subsurface 3InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Peak Elev=177.65'Storage=15 cf0.24 cfs0.23 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 216HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4: Surface 4Inflow Area = 2,525 sf, 10.02% Impervious, Inflow Depth = 4.08" for 25-YR eventInflow = 0.27 cfs @ 12.13 hrs, Volume= 858 cfOutflow = 0.24 cfs @ 12.17 hrs, Volume= 858 cf, Atten= 13%, Lag= 2.1 minPrimary = 0.22 cfs @ 12.17 hrs, Volume= 404 cf Routed to Pond 5 : Surface 5Secondary = 0.02 cfs @ 12.17 hrs, Volume= 455 cf Routed to Pond 4S : Subsurface 4Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.39' @ 12.17 hrs Surf.Area= 201 sf Storage= 93 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 22.2 min ( 838.0 - 815.8 )Volume Invert Avail.Storage Storage Description#1 182.50' 119 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 14 0 0183.00 114 32 32183.51 229 87 119Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.22 cfs @ 12.17 hrs HW=183.38' TW=182.89' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.15 cfs @ 2.43 fps)4=Orifice/Grate (Orifice Controls 0.07 cfs @ 1.18 fps)Secondary OutFlow Max=0.02 cfs @ 12.17 hrs HW=183.38' TW=178.26' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.02 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 217HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4: Surface 4InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,525 sfPeak Elev=183.39'Storage=93 cf0.27 cfs0.24 cfs0.22 cfs0.02 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 218HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4S: Subsurface 4Inflow = 0.02 cfs @ 12.17 hrs, Volume= 455 cfOutflow = 0.02 cfs @ 12.22 hrs, Volume= 454 cf, Atten= 4%, Lag= 3.4 minPrimary = 0.02 cfs @ 12.22 hrs, Volume= 454 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.27' @ 12.22 hrs Surf.Area= 229 sf Storage= 9 cfPlug-Flow detention time= 14.1 min calculated for 454 cf (100% of inflow)Center-of-Mass det. time= 13.1 min ( 934.8 - 921.7 )Volume Invert Avail.Storage Storage Description#1 178.17' 212 cfCustom Stage Data (Prismatic) Listed below (Recalc)534 cf Overall - 3 cf Embedded = 530 cf x 40.0% Voids#2 178.18' 3 cf4.0" Round Pipe Storage Inside #1L= 36.0'215 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.17 229 0 0180.50 229 534 534Device Routing Invert Outlet Devices#1 Primary 178.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.22 hrs HW=178.27' TW=177.78' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 1.00 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 219HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4S: Subsurface 4InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=178.27'Storage=9 cf0.02 cfs0.02 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 220HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5: Surface 5Inflow Area = 2,697 sf, 10.53% Impervious, Inflow Depth = 2.06" for 25-YR eventInflow = 0.24 cfs @ 12.16 hrs, Volume= 464 cfOutflow = 0.23 cfs @ 12.18 hrs, Volume= 464 cf, Atten= 2%, Lag= 0.9 minPrimary = 0.23 cfs @ 12.18 hrs, Volume= 386 cf Routed to Pond 6 : Surface 6Secondary = 0.01 cfs @ 12.18 hrs, Volume= 77 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.89' @ 12.18 hrs Surf.Area= 61 sf Storage= 28 cfPlug-Flow detention time= 7.0 min calculated for 464 cf (100% of inflow)Center-of-Mass det. time= 7.0 min ( 759.7 - 752.7 )Volume Invert Avail.Storage Storage Description#1 182.00' 36 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 36 10 10183.01 68 27 36Device Routing Invert Outlet Devices#1 Secondary 182.00'4.000 in/hr Exfiltration over Surface area #2 Primary 183.00'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.23 cfs @ 12.18 hrs HW=182.89' TW=182.40' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.15 cfs @ 2.46 fps)4=Orifice/Grate (Orifice Controls 0.07 cfs @ 1.21 fps)Secondary OutFlow Max=0.01 cfs @ 12.18 hrs HW=182.89' TW=177.78' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 221HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5: Surface 5InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,697 sfPeak Elev=182.89'Storage=28 cf0.24 cfs0.23 cfs0.23 cfs0.01 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 222HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5S: Subsurface 5Inflow = 0.02 cfs @ 12.21 hrs, Volume= 531 cfOutflow = 0.02 cfs @ 12.23 hrs, Volume= 531 cf, Atten= 0%, Lag= 1.2 minPrimary = 0.02 cfs @ 12.23 hrs, Volume= 531 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.78' @ 12.23 hrs Surf.Area= 68 sf Storage= 3 cfPlug-Flow detention time= 4.0 min calculated for 531 cf (100% of inflow)Center-of-Mass det. time= 3.6 min ( 925.4 - 921.9 )Volume Invert Avail.Storage Storage Description#1 177.67' 63 cfCustom Stage Data (Prismatic) Listed below (Recalc)158 cf Overall - 1 cf Embedded = 157 cf x 40.0% Voids#2 177.68' 1 cf4.0" Round Pipe Storage Inside #1L= 12.0'64 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.67 68 0 0180.00 68 158 158Device Routing Invert Outlet Devices#1 Primary 177.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.23 hrs HW=177.78' TW=177.29' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 1.07 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 223HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5S: Subsurface 5InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Peak Elev=177.78'Storage=3 cf0.02 cfs0.02 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 224HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6: Surface 6Inflow Area = 2,885 sf, 11.82% Impervious, Inflow Depth = 1.89" for 25-YR eventInflow = 0.24 cfs @ 12.17 hrs, Volume= 455 cfOutflow = 0.24 cfs @ 12.19 hrs, Volume= 455 cf, Atten= 1%, Lag= 0.9 minPrimary = 0.23 cfs @ 12.19 hrs, Volume= 378 cf Routed to Pond 7 : Surface 7Secondary = 0.01 cfs @ 12.19 hrs, Volume= 77 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.40' @ 12.19 hrs Surf.Area= 58 sf Storage= 30 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 6.8 min ( 758.9 - 752.1 )Volume Invert Avail.Storage Storage Description#1 181.50' 37 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 2 0 0182.00 40 11 11182.51 63 26 37Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 182.50'9.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.23 cfs @ 12.19 hrs HW=182.40' TW=181.42' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.16 cfs @ 2.50 fps)4=Orifice/Grate (Orifice Controls 0.08 cfs @ 1.24 fps)Secondary OutFlow Max=0.01 cfs @ 12.19 hrs HW=182.40' TW=177.29' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 225HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6: Surface 6InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,885 sfPeak Elev=182.40'Storage=30 cf0.24 cfs0.24 cfs0.23 cfs0.01 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 226HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6S: Subsurface 6Inflow = 0.03 cfs @ 12.22 hrs, Volume= 608 cfOutflow = 0.03 cfs @ 12.24 hrs, Volume= 608 cf, Atten= 0%, Lag= 1.0 minPrimary = 0.03 cfs @ 12.24 hrs, Volume= 608 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.29' @ 12.24 hrs Surf.Area= 63 sf Storage= 3 cfPlug-Flow detention time= 3.7 min calculated for 608 cf (100% of inflow)Center-of-Mass det. time= 3.1 min ( 917.9 - 914.7 )Volume Invert Avail.Storage Storage Description#1 177.17' 58 cfCustom Stage Data (Prismatic) Listed below (Recalc)147 cf Overall - 1 cf Embedded = 146 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 13.0'59 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 63 0 0179.50 63 147 147Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.03 cfs @ 12.24 hrs HW=177.29' TW=176.74' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.03 cfs @ 1.13 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 227HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6S: Subsurface 6InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Peak Elev=177.29'Storage=3 cf0.03 cfs0.03 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 228HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7: Surface 7Inflow Area = 3,343 sf, 13.79% Impervious, Inflow Depth = 1.96" for 25-YR eventInflow = 0.27 cfs @ 12.18 hrs, Volume= 546 cfOutflow = 0.26 cfs @ 12.20 hrs, Volume= 546 cf, Atten= 4%, Lag= 1.6 minPrimary = 0.25 cfs @ 12.20 hrs, Volume= 403 cf Routed to Pond 8 : Surface 8Secondary = 0.01 cfs @ 12.20 hrs, Volume= 143 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.42' @ 12.20 hrs Surf.Area= 106 sf Storage= 58 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 15.6 min ( 777.5 - 761.9 )Volume Invert Avail.Storage Storage Description#1 180.00' 69 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)180.00 2 0 0180.50 18 5 5181.00 58 19 24181.51 117 45 69Device Routing Invert Outlet Devices#1 Secondary 180.00'4.000 in/hr Exfiltration over Surface area #2 Primary 181.50'10.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 181.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 181.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.25 cfs @ 12.20 hrs HW=181.42' TW=180.10' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.16 cfs @ 2.58 fps)4=Orifice/Grate (Orifice Controls 0.09 cfs @ 1.31 fps)Secondary OutFlow Max=0.01 cfs @ 12.20 hrs HW=181.42' TW=176.82' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 229HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7: Surface 7InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=3,343 sfPeak Elev=181.42'Storage=58 cf0.27 cfs0.26 cfs0.25 cfs0.01 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 230HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7S: Subsurface 7[62] Hint: Exceeded Reach P1 OUTLET depth by 0.50' @ 12.20 hrsInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 7.94" for 25-YR eventInflow = 0.31 cfs @ 12.16 hrs, Volume= 1,667 cfOutflow = 0.29 cfs @ 12.19 hrs, Volume= 1,667 cf, Atten= 5%, Lag= 1.8 minPrimary = 0.29 cfs @ 12.19 hrs, Volume= 1,667 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 176.82' @ 12.19 hrs Surf.Area= 117 sf Storage= 31 cfPlug-Flow detention time= 3.8 min calculated for 1,667 cf (100% of inflow)Center-of-Mass det. time= 3.4 min ( 864.1 - 860.7 )Volume Invert Avail.Storage Storage Description#1 176.17' 108 cfCustom Stage Data (Prismatic) Listed below (Recalc)273 cf Overall - 2 cf Embedded = 271 cf x 40.0% Voids#2 176.18' 2 cf4.0" Round Pipe Storage Inside #1L= 21.0'110 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)176.17 117 0 0178.50 117 273 273Device Routing Invert Outlet Devices#1 Primary 176.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.29 cfs @ 12.19 hrs HW=176.82' TW=175.30' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.29 cfs @ 3.31 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 231HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7S: Subsurface 7InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfPeak Elev=176.82'Storage=31 cf0.31 cfs0.29 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 232HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8: Surface 8Inflow Area = 3,973 sf, 13.21% Impervious, Inflow Depth = 1.86" for 25-YR eventInflow = 0.30 cfs @ 12.18 hrs, Volume= 617 cfOutflow = 0.30 cfs @ 12.20 hrs, Volume= 617 cf, Atten= 1%, Lag= 0.8 minPrimary = 0.28 cfs @ 12.20 hrs, Volume= 368 cf Routed to Reach P2 : 8" PipeSecondary = 0.02 cfs @ 12.20 hrs, Volume= 249 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 180.10' @ 12.20 hrs Surf.Area= 167 sf Storage= 85 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 22.7 min ( 791.0 - 768.3 )Volume Invert Avail.Storage Storage Description#1 179.00' 164 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)179.00 7 0 0179.50 49 14 14179.75 120 21 35180.50 223 129 164Device Routing Invert Outlet Devices#1 Secondary 179.00'4.000 in/hr Exfiltration over Surface area #2 Primary 180.00'12inch-Dome Grate Capacity Primary OutFlow Max=0.28 cfs @ 12.20 hrs HW=180.10' TW=174.80' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.28 cfs)Secondary OutFlow Max=0.02 cfs @ 12.20 hrs HW=180.10' TW=175.30' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.02 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 233HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8: Surface 8InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=3,973 sfPeak Elev=180.10'Storage=85 cf0.30 cfs0.30 cfs0.28 cfs0.02 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 234HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8S: Subsurface 8Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 9.13" for 25-YR eventInflow = 0.30 cfs @ 12.19 hrs, Volume= 1,916 cfOutflow = 0.29 cfs @ 12.23 hrs, Volume= 1,916 cf, Atten= 4%, Lag= 1.9 minPrimary = 0.29 cfs @ 12.23 hrs, Volume= 1,916 cf Routed to Reach P2 : 8" PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 175.33' @ 12.23 hrs Surf.Area= 120 sf Storage= 33 cfPlug-Flow detention time= 3.7 min calculated for 1,916 cf (100% of inflow)Center-of-Mass det. time= 3.2 min ( 867.2 - 864.0 )Volume Invert Avail.Storage Storage Description#1 174.67' 111 cfCustom Stage Data (Prismatic) Listed below (Recalc)280 cf Overall - 2 cf Embedded = 278 cf x 40.0% Voids#2 174.68' 2 cf4.0" Round Pipe Storage Inside #1L= 24.0'113 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.67 120 0 0177.00 120 280 280Device Routing Invert Outlet Devices#1 Primary 174.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.29 cfs @ 12.23 hrs HW=175.33' TW=174.80' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.29 cfs @ 3.33 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 235HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8S: Subsurface 8InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfPeak Elev=175.33'Storage=33 cf0.30 cfs0.29 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 236HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9: Surface 9Inflow Area = 3,923 sf, 27.20% Impervious, Inflow Depth = 4.40" for 25-YR eventInflow = 0.45 cfs @ 12.13 hrs, Volume= 1,437 cfOutflow = 0.45 cfs @ 12.13 hrs, Volume= 1,437 cf, Atten= 0%, Lag= 0.2 minPrimary = 0.44 cfs @ 12.13 hrs, Volume= 1,170 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.13 hrs, Volume= 267 cf Routed to Pond 9S : Subsurface 9Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.38' @ 12.13 hrs Surf.Area= 65 sf Storage= 12 cfPlug-Flow detention time= 4.2 min calculated for 1,437 cf (100% of inflow)Center-of-Mass det. time= 4.2 min ( 810.9 - 806.6 )Volume Invert Avail.Storage Storage Description#1 174.00' 86 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.00 1 0 0175.00 170 86 86Device Routing Invert Outlet Devices#1 Primary 174.25'12inch-Dome Grate Capacity #2 Secondary 174.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.44 cfs @ 12.13 hrs HW=174.38' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.44 cfs)Secondary OutFlow Max=0.01 cfs @ 12.13 hrs HW=174.38' TW=170.73' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 237HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9: Surface 9InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.50.450.40.350.30.250.20.150.10.050Inflow Area=3,923 sfPeak Elev=174.38'Storage=12 cf0.45 cfs0.45 cfs0.44 cfs0.01 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 238HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9S: Subsurface 9Inflow = 0.01 cfs @ 12.13 hrs, Volume= 267 cfOutflow = 0.01 cfs @ 12.22 hrs, Volume= 265 cf, Atten= 11%, Lag= 5.1 minPrimary = 0.01 cfs @ 12.22 hrs, Volume= 265 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 170.73' @ 12.22 hrs Surf.Area= 170 sf Storage= 10 cfPlug-Flow detention time= 37.8 min calculated for 265 cf (99% of inflow)Center-of-Mass det. time= 34.5 min ( 958.9 - 924.3 )Volume Invert Avail.Storage Storage Description#1 170.67' 395 cfCustom Stage Data (Prismatic) Listed below (Recalc)396 cf Overall - 1 cf Embedded = 395 cf#2 170.68' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'396 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)170.67 170 0 0173.00 170 396 396Device Routing Invert Outlet Devices#1 Primary 170.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.22 hrs HW=170.73' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.73 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 239HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9S: Subsurface 9InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0070.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Peak Elev=170.73'Storage=10 cf0.01 cfs0.01 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 240HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10: Surface 10Inflow Area = 3,386 sf, 9.57% Impervious, Inflow Depth = 4.08" for 25-YR eventInflow = 0.37 cfs @ 12.13 hrs, Volume= 1,151 cfOutflow = 0.36 cfs @ 12.14 hrs, Volume= 1,151 cf, Atten= 0%, Lag= 0.4 minPrimary = 0.35 cfs @ 12.14 hrs, Volume= 668 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.14 hrs, Volume= 483 cf Routed to Pond 10S : Subsurface 10Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.36' @ 12.14 hrs Surf.Area= 121 sf Storage= 34 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 10.9 min ( 826.7 - 815.8 )Volume Invert Avail.Storage Storage Description#1 173.00' 142 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)173.00 68 0 0174.00 215 142 142Device Routing Invert Outlet Devices#1 Primary 173.25'12inch-Dome Grate Capacity #2 Secondary 173.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.35 cfs @ 12.14 hrs HW=173.36' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.35 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=173.36' TW=168.74' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 241HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10: Surface 10InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=3,386 sfPeak Elev=173.36'Storage=34 cf0.37 cfs0.36 cfs0.35 cfs0.01 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 242HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10S: Subsurface 10Inflow = 0.01 cfs @ 12.14 hrs, Volume= 483 cfOutflow = 0.01 cfs @ 12.18 hrs, Volume= 482 cf, Atten= 2%, Lag= 2.6 minPrimary = 0.01 cfs @ 12.18 hrs, Volume= 482 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 168.74' @ 12.18 hrs Surf.Area= 215 sf Storage= 6 cfPlug-Flow detention time= 11.5 min calculated for 482 cf (100% of inflow)Center-of-Mass det. time= 10.7 min ( 949.5 - 938.8 )Volume Invert Avail.Storage Storage Description#1 168.67' 200 cfCustom Stage Data (Prismatic) Listed below (Recalc)501 cf Overall - 2 cf Embedded = 499 cf x 40.0% Voids#2 168.68' 2 cf4.0" Round Pipe Storage Inside #1L= 18.0'201 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)168.67 215 0 0171.00 215 501 501Device Routing Invert Outlet Devices#1 Primary 168.68'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.18 hrs HW=168.74' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.83 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 243HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10S: Subsurface 10InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0130.0120.0110.0110.010.010.0090.0090.0080.0080.0070.0070.0060.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Peak Elev=168.74'Storage=6 cf0.01 cfs0.01 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 244HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11: Surface 11Inflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 4.62" for 25-YR eventInflow = 0.25 cfs @ 12.13 hrs, Volume= 1,110 cfOutflow = 0.25 cfs @ 12.14 hrs, Volume= 1,110 cf, Atten= 1%, Lag= 0.5 minPrimary = 0.24 cfs @ 12.14 hrs, Volume= 439 cf Routed to Reach P3 : 4" Outlet PipeSecondary = 0.01 cfs @ 12.14 hrs, Volume= 671 cf Routed to Pond 11S : Subsurface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 185.38' @ 12.14 hrs Surf.Area= 116 sf Storage= 53 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 39.0 min ( 1,016.7 - 977.8 )Volume Invert Avail.Storage Storage Description#1 184.50' 284 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)184.50 23 0 0185.00 56 20 20186.00 211 134 153186.50 310 130 284Device Routing Invert Outlet Devices#1 Secondary 184.50'4.000 in/hr Exfiltration over Surface area #2 Primary 185.30'12inch-Dome Grate Capacity Primary OutFlow Max=0.24 cfs @ 12.14 hrs HW=185.38' TW=183.30' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.24 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=185.38' TW=183.30' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 245HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11: Surface 11InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,880 sfPeak Elev=185.38'Storage=53 cf0.25 cfs0.25 cfs0.24 cfs0.01 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 246HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11S: Subsurface 11[90] Warning: Qout>Qin may require smaller dt or Finer RoutingInflow = 0.01 cfs @ 12.14 hrs, Volume= 671 cfOutflow = 0.02 cfs @ 12.23 hrs, Volume= 671 cf, Atten= 0%, Lag= 5.3 minPrimary = 0.02 cfs @ 12.23 hrs, Volume= 671 cf Routed to Reach P3 : 4" Outlet PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.31' @ 12.17 hrs Surf.Area= 310 sf Storage= 17 cfPlug-Flow detention time= 18.2 min calculated for 671 cf (100% of inflow)Center-of-Mass det. time= 18.0 min ( 1,198.1 - 1,180.1 )Volume Invert Avail.Storage Storage Description#1 183.17' 289 cfCustom Stage Data (Prismatic) Listed below (Recalc)722 cf Overall x 40.0% VoidsElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)183.17 310 0 0185.50 310 722 722Device Routing Invert Outlet Devices#1 Primary 183.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.23 hrs HW=183.30' TW=183.28' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 0.65 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 247HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11S: Subsurface 11InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0210.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=183.31'Storage=17 cf0.01 cfs0.02 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 248HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 29P: Landscape FilterInflow Area = 5,639 sf,100.00% Impervious, Inflow Depth = 5.66" for 25-YR eventInflow = 0.52 cfs @ 12.13 hrs, Volume= 2,658 cfOutflow = 0.46 cfs @ 12.18 hrs, Volume= 2,653 cf, Atten= 12%, Lag= 3.2 minPrimary = 0.46 cfs @ 12.18 hrs, Volume= 2,653 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 170.99' @ 12.18 hrs Surf.Area= 1,000 sf Storage= 198 cfPlug-Flow detention time= 21.3 min calculated for 2,653 cf (100% of inflow)Center-of-Mass det. time= 20.4 min ( 767.1 - 746.6 )Volume Invert Avail.Storage Storage Description#1 170.50' 1,000 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Voids Inc.Store Cum.Store(feet) (sq-ft) (%) (cubic-feet) (cubic-feet)170.50 1,000 0.0 0 0170.51 1,000 40.0 4 4171.50 1,000 40.0 396 400171.51 1,000 20.0 2 402174.50 1,000 20.0 598 1,000Device Routing Invert Outlet Devices#1 Primary 170.51'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.46 cfs @ 12.18 hrs HW=170.99' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.46 cfs @ 2.37 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 249HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 29P: Landscape FilterInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.550.50.450.40.350.30.250.20.150.10.050Inflow Area=5,639 sfPeak Elev=170.99'Storage=198 cf0.52 cfs0.46 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 250HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 30P: Porous PaversInflow Area = 443 sf, 33.86% Impervious, Inflow Depth = 4.50" for 25-YR eventInflow = 0.00 cfs @ 20.97 hrs, Volume= 166 cfOutflow = 0.00 cfs @ 21.04 hrs, Volume= 166 cf, Atten= 0%, Lag= 3.9 minPrimary = 0.00 cfs @ 21.04 hrs, Volume= 166 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.97' @ 21.04 hrs Surf.Area= 150 sf Storage= 3 cfPlug-Flow detention time= 21.3 min calculated for 166 cf (100% of inflow)Center-of-Mass det. time= 16.6 min ( 1,442.4 - 1,425.7 )Volume Invert Avail.Storage Storage Description#1 174.92' 135 cf31" section beneath paver (Prismatic) Listed below (Recalc)387 cf Overall - 2 cf Embedded = 385 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'137 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 150 0 0177.50 150 387 387Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 21.04 hrs HW=174.97' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.66 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 251HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 30P: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0040.0040.0040.0030.0030.0030.0030.0030.0020.0020.0020.0020.0020.0010.0010.0010.0010.0010.0000.0000Inflow Area=443 sfPeak Elev=174.97'Storage=3 cf0.00 cfs0.00 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 252HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 31P: Distribution Pipes[57] Hint: Peaked at 173.90' (Flood elevation advised)Inflow Area = 2,750 sf,100.00% Impervious, Inflow Depth = 5.86" for 25-YR eventInflow = 0.37 cfs @ 12.13 hrs, Volume= 1,343 cfOutflow = 0.37 cfs @ 12.13 hrs, Volume= 1,343 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.25 cfs @ 12.13 hrs, Volume= 1,297 cf Routed to Pond 29P : Landscape FilterSecondary = 0.11 cfs @ 12.13 hrs, Volume= 47 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.90' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'6.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.25 cfs @ 12.13 hrs HW=173.90' TW=170.97' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.25 cfs @ 2.91 fps)Secondary OutFlow Max=0.11 cfs @ 12.13 hrs HW=173.90' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.11 cfs @ 1.53 fps)Pond 31P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,750 sfPeak Elev=173.90'0.37 cfs0.37 cfs0.25 cfs0.11 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 253HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 33P: Distribution Pipes[57] Hint: Peaked at 173.95' (Flood elevation advised)Inflow Area = 2,889 sf,100.00% Impervious, Inflow Depth = 5.86" for 25-YR eventInflow = 0.39 cfs @ 12.13 hrs, Volume= 1,411 cfOutflow = 0.39 cfs @ 12.13 hrs, Volume= 1,411 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.27 cfs @ 12.13 hrs, Volume= 1,361 cf Routed to Pond 29P : Landscape FilterSecondary = 0.12 cfs @ 12.13 hrs, Volume= 50 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.95' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'4.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.27 cfs @ 12.13 hrs HW=173.95' TW=170.97' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.27 cfs @ 3.08 fps)Secondary OutFlow Max=0.12 cfs @ 12.13 hrs HW=173.95' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.12 cfs @ 1.69 fps)Pond 33P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,889 sfPeak Elev=173.95'0.39 cfs0.39 cfs0.27 cfs0.12 cfs NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 254HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PN: Porous PaversInflow Area = 676 sf, 77.51% Impervious, Inflow Depth = 5.40" for 25-YR eventInflow = 0.01 cfs @ 20.23 hrs, Volume= 304 cfOutflow = 0.01 cfs @ 20.93 hrs, Volume= 302 cf, Atten= 0%, Lag= 42.1 minPrimary = 0.01 cfs @ 20.93 hrs, Volume= 302 cf Routed to Pond 11 : Surface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 188.49' @ 20.93 hrs Surf.Area= 464 sf Storage= 11 cfPlug-Flow detention time= 49.9 min calculated for 302 cf (99% of inflow)Center-of-Mass det. time= 41.9 min ( 1,435.0 - 1,393.1 )Volume Invert Avail.Storage Storage Description#1 188.42' 417 cf31" section beneath pavers (Prismatic) Listed below (Recalc)1,197 cf Overall - 6 cf Embedded = 1,191 cf x 35.0% Voids#2 188.43' 6 cf4.0" Round Pipe Storage Inside #1L= 67.0'423 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)188.42 464 0 0191.00 464 1,197 1,197Device Routing Invert Outlet Devices#1 Primary 188.43'4.0" Round Culvert L= 7.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 188.43' / 186.00' S= 0.3471 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.09 sf Primary OutFlow Max=0.01 cfs @ 20.93 hrs HW=188.49' TW=185.30' (Dynamic Tailwater)1=Culvert (Inlet Controls 0.01 cfs @ 0.65 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 255HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PN: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0070.0070.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Inflow Area=676 sfPeak Elev=188.49'Storage=11 cf4.0"Round Culvertn=0.013L=7.0'S=0.3471 '/'0.01 cfs0.01 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 256HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PS: Porous PaversInflow Area = 2,379 sf, 11.60% Impervious, Inflow Depth = 4.08" for 25-YR eventInflow = 0.02 cfs @ 20.97 hrs, Volume= 809 cfOutflow = 0.02 cfs @ 21.09 hrs, Volume= 808 cf, Atten= 0%, Lag= 7.0 minPrimary = 0.02 cfs @ 21.09 hrs, Volume= 808 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 175.02' @ 21.09 hrs Surf.Area= 248 sf Storage= 9 cfPlug-Flow detention time= 13.5 min calculated for 808 cf (100% of inflow)Center-of-Mass det. time= 11.6 min ( 1,450.0 - 1,438.4 )Volume Invert Avail.Storage Storage Description#1 174.92' 223 cf31" section beneath paver (Prismatic) Listed below (Recalc)640 cf Overall - 2 cf Embedded = 637 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'226 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 248 0 0177.50 248 640 640Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 21.09 hrs HW=175.02' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 1.00 fps) NOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 257HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PS: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Inflow Area=2,379 sfPeak Elev=175.02'Storage=9 cf0.02 cfs0.02 cfsNOAA 24-hr D 25-YR Rainfall=6.10"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 258HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Link 33L: On-site Closed DrainageInflow Area = 27,635 sf, 35.49% Impervious, Inflow Depth = 4.56" for 25-YR eventInflow = 2.45 cfs @ 12.14 hrs, Volume= 10,508 cfPrimary = 2.45 cfs @ 12.14 hrs, Volume= 10,508 cf, Atten= 0%, Lag= 0.0 min Routed to Reach DP-PR : Proposed SitePrimary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsLink 33L: On-site Closed DrainageInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)210Inflow Area=27,635 sf2.45 cfs2.45 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 259HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCTime span=0.00-100.00 hrs, dt=0.01 hrs, 10001 points x 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CNReach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind methodRunoff Area=1,918 sf 33.52% Impervious Runoff Depth=6.22"Subcatchment PR1: Basin 1 Tc=6.0 min CN=86 Runoff=0.30 cfs 995 cfRunoff Area=3,386 sf 9.57% Impervious Runoff Depth=5.76"Subcatchment PR10: Basin 10 Tc=6.0 min CN=82 Runoff=0.51 cfs 1,624 cfRunoff Area=2,204 sf 27.72% Impervious Runoff Depth=6.11"Subcatchment PR11: Basin 11 Tc=6.0 min CN=85 Runoff=0.34 cfs 1,122 cfRunoff Area=2,493 sf 1.36% Impervious Runoff Depth=5.52"Subcatchment PR12: West site to Area Drain Tc=6.0 min CN=80 Runoff=0.36 cfs 1,147 cfRunoff Area=2,379 sf 11.60% Impervious Runoff Depth=5.76"Subcatchment PR13: Pavers front Tc=674.0 min CN=82 Runoff=0.03 cfs 1,141 cfRunoff Area=676 sf 77.51% Impervious Runoff Depth=7.17"Subcatchment PR14: Pavers North Tc=674.0 min CN=94 Runoff=0.01 cfs 404 cfRunoff Area=2,750 sf 100.00% Impervious Runoff Depth=7.65"Subcatchment PR15a: Roof West Tc=6.0 min CN=98 Runoff=0.48 cfs 1,753 cfRunoff Area=2,889 sf 100.00% Impervious Runoff Depth=7.65"Subcatchment PR15b: Roof East Tc=6.0 min CN=98 Runoff=0.50 cfs 1,842 cfRunoff Area=13,694 sf 44.87% Impervious Runoff Depth=6.46"Subcatchment PR16: Remainder of site Tc=6.0 min CN=88 Runoff=2.22 cfs 7,373 cfRunoff Area=443 sf 33.86% Impervious Runoff Depth=6.22"Subcatchment PR17: Pavers path Tc=674.0 min CN=86 Runoff=0.01 cfs 230 cfRunoff Area=164 sf 0.00% Impervious Runoff Depth=5.52"Subcatchment PR2: Basin 2 Tc=6.0 min CN=80 Runoff=0.02 cfs 75 cfRunoff Area=437 sf 3.20% Impervious Runoff Depth=5.64"Subcatchment PR3: Basin 3 Tc=6.0 min CN=81 Runoff=0.06 cfs 205 cfRunoff Area=2,525 sf 10.02% Impervious Runoff Depth=5.76"Subcatchment PR4: Basin 4 Tc=6.0 min CN=82 Runoff=0.38 cfs 1,211 cfRunoff Area=172 sf 18.02% Impervious Runoff Depth=5.87"Subcatchment PR5: Basin 5 Tc=6.0 min CN=83 Runoff=0.03 cfs 84 cfRunoff Area=188 sf 30.32% Impervious Runoff Depth=6.11"Subcatchment PR6: Basin 6 Tc=6.0 min CN=85 Runoff=0.03 cfs 96 cfRunoff Area=458 sf 26.20% Impervious Runoff Depth=6.11"Subcatchment PR7: Basin 7 Tc=6.0 min CN=85 Runoff=0.07 cfs 233 cfNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 260HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCRunoff Area=630 sf 10.16% Impervious Runoff Depth=5.76"Subcatchment PR8: Basin 8 Tc=6.0 min CN=82 Runoff=0.09 cfs 302 cfRunoff Area=3,923 sf 27.20% Impervious Runoff Depth=6.11"Subcatchment PR9: Basin 9 Tc=6.0 min CN=85 Runoff=0.61 cfs 1,997 cf Inflow=5.54 cfs 21,821 cfReach DP-PR: Proposed Site Outflow=5.54 cfs 21,821 cfAvg. Flow Depth=0.17' Max Vel=6.09 fps Inflow=0.35 cfs 1,275 cfReach P1: 4" Pipe Under Path6.0" Round Pipe n=0.013 L=15.0' S=0.0667 '/' Capacity=1.45 cfs Outflow=0.35 cfs 1,275 cfAvg. Flow Depth=0.36' Max Vel=4.05 fps Inflow=0.77 cfs 3,199 cfReach P2: 8" Pipe8.0" Round Pipe n=0.013 L=65.0' S=0.0129 '/' Capacity=1.37 cfs Outflow=0.77 cfs 3,199 cfAvg. Flow Depth=0.16' Max Vel=6.24 fps Inflow=0.33 cfs 1,524 cfReach P3: 4" Outlet Pipe6.0" Round Pipe n=0.013 L=136.0' S=0.0748 '/' Capacity=1.53 cfs Outflow=0.33 cfs 1,524 cfPeak Elev=183.45' Storage=20 cf Inflow=0.30 cfs 995 cfPond 1: Surface 1 Primary=0.29 cfs 858 cf Secondary=0.00 cfs 137 cf Outflow=0.30 cfs 995 cfPeak Elev=178.28' Storage=3 cf Inflow=0.00 cfs 137 cfPond 1S: Subsurface 1 Outflow=0.02 cfs 136 cfPeak Elev=182.00' Storage=0 cf Inflow=0.32 cfs 934 cfPond 2: Surface 2 Primary=0.00 cfs 0 cf Secondary=0.32 cfs 934 cf Outflow=0.32 cfs 934 cfPeak Elev=178.38' Storage=17 cf Inflow=0.32 cfs 1,070 cfPond 2S: Subsurface 2 Outflow=0.31 cfs 1,070 cfPeak Elev=181.83' Storage=11 cf Inflow=0.06 cfs 205 cfPond 3: Surface 3 Primary=0.06 cfs 77 cf Secondary=0.00 cfs 128 cf Outflow=0.06 cfs 205 cfPeak Elev=177.86' Storage=21 cf Inflow=0.31 cfs 1,198 cfPond 3S: Subsurface 3 Outflow=0.30 cfs 1,198 cfPeak Elev=183.47' Storage=110 cf Inflow=0.38 cfs 1,211 cfPond 4: Surface 4 Primary=0.31 cfs 651 cf Secondary=0.02 cfs 561 cf Outflow=0.33 cfs 1,211 cfPeak Elev=178.27' Storage=10 cf Inflow=0.02 cfs 561 cfPond 4S: Subsurface 4 Outflow=0.02 cfs 560 cfPeak Elev=182.98' Storage=34 cf Inflow=0.34 cfs 735 cfPond 5: Surface 5 Primary=0.33 cfs 632 cf Secondary=0.01 cfs 102 cf Outflow=0.33 cfs 735 cfPeak Elev=177.78' Storage=3 cf Inflow=0.03 cfs 662 cfPond 5S: Subsurface 5 Outflow=0.03 cfs 662 cfPeak Elev=182.49' Storage=36 cf Inflow=0.35 cfs 728 cfPond 6: Surface 6 Primary=0.34 cfs 628 cf Secondary=0.01 cfs 100 cf Outflow=0.35 cfs 728 cf NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 261HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPeak Elev=177.30' Storage=3 cf Inflow=0.03 cfs 762 cfPond 6S: Subsurface 6 Outflow=0.03 cfs 761 cfPeak Elev=181.51' Storage=68 cf Inflow=0.40 cfs 861 cfPond 7: Surface 7 Primary=0.38 cfs 680 cf Secondary=0.01 cfs 181 cf Outflow=0.39 cfs 861 cfPeak Elev=177.11' Storage=45 cf Inflow=0.39 cfs 2,218 cfPond 7S: Subsurface 7 Outflow=0.37 cfs 2,217 cfPeak Elev=180.13' Storage=90 cf Inflow=0.45 cfs 982 cfPond 8: Surface 8 Primary=0.43 cfs 670 cf Secondary=0.02 cfs 312 cf Outflow=0.45 cfs 982 cfPeak Elev=175.61' Storage=46 cf Inflow=0.38 cfs 2,529 cfPond 8S: Subsurface 8 Outflow=0.37 cfs 2,528 cfPeak Elev=174.41' Storage=14 cf Inflow=0.61 cfs 1,997 cfPond 9: Surface 9 Primary=0.60 cfs 1,709 cf Secondary=0.01 cfs 288 cf Outflow=0.61 cfs 1,997 cfPeak Elev=170.73' Storage=10 cf Inflow=0.01 cfs 288 cfPond 9S: Subsurface 9 Outflow=0.01 cfs 286 cfPeak Elev=173.39' Storage=37 cf Inflow=0.51 cfs 1,624 cfPond 10: Surface 10 Primary=0.49 cfs 1,051 cf Secondary=0.01 cfs 573 cf Outflow=0.50 cfs 1,624 cfPeak Elev=168.74' Storage=6 cf Inflow=0.01 cfs 573 cfPond 10S: Subsurface 10 Outflow=0.01 cfs 572 cfPeak Elev=185.41' Storage=55 cf Inflow=0.34 cfs 1,524 cfPond 11: Surface 11 Primary=0.33 cfs 777 cf Secondary=0.01 cfs 747 cf Outflow=0.34 cfs 1,524 cfPeak Elev=183.33' Storage=19 cf Inflow=0.01 cfs 747 cfPond 11S: Subsurface 11 Outflow=0.02 cfs 747 cfPeak Elev=171.05' Storage=220 cf Inflow=0.59 cfs 3,392 cfPond 29P: Landscape Filter Outflow=0.51 cfs 3,388 cfPeak Elev=174.97' Storage=3 cf Inflow=0.01 cfs 230 cfPond 30P: Porous Pavers Outflow=0.01 cfs 229 cfPeak Elev=173.98' Inflow=0.48 cfs 1,753 cfPond 31P: Distribution Pipes Primary=0.28 cfs 1,653 cf Secondary=0.20 cfs 100 cf Outflow=0.48 cfs 1,753 cfPeak Elev=174.08' Inflow=0.50 cfs 1,842 cfPond 33P: Distribution Pipes Primary=0.31 cfs 1,739 cf Secondary=0.19 cfs 103 cf Outflow=0.50 cfs 1,842 cfPeak Elev=188.50' Storage=13 cf Inflow=0.01 cfs 404 cfPond PN: Porous Pavers4.0" Round Culvert n=0.013 L=7.0' S=0.3471 '/' Outflow=0.01 cfs 402 cfPeak Elev=175.03' Storage=10 cf Inflow=0.03 cfs 1,141 cfPond PS: Porous Pavers Outflow=0.03 cfs 1,140 cfNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 262HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLC Inflow=3.34 cfs 14,448 cfLink 33L: On-site Closed Drainage Primary=3.34 cfs 14,448 cfTotal Runoff Area = 41,329 sf Runoff Volume = 21,834 cf Average Runoff Depth = 6.34"61.40% Pervious = 25,378 sf 38.60% Impervious = 15,951 sf NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 263HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR1: Basin 1Runoff = 0.30 cfs @ 12.13 hrs, Volume= 995 cf, Depth= 6.22" Routed to Pond 1 : Surface 1Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 643 98 Site Impervious1,275 80 >75% Grass cover, Good, HSG D1,918 86 Weighted Average1,275 66.48% Pervious Area643 33.52% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR1: Basin 1RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=1,918 sfRunoff Volume=995 cfRunoff Depth=6.22"Tc=6.0 minCN=860.30 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 264HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR10: Basin 10Runoff = 0.51 cfs @ 12.13 hrs, Volume= 1,624 cf, Depth= 5.76" Routed to Pond 10 : Surface 10Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 324 98 Site Impervious3,062 80 >75% Grass cover, Good, HSG D3,386 82 Weighted Average3,062 90.43% Pervious Area324 9.57% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR10: Basin 10RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.550.50.450.40.350.30.250.20.150.10.050NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=3,386 sfRunoff Volume=1,624 cfRunoff Depth=5.76"Tc=6.0 minCN=820.51 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 265HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR11: Basin 11Runoff = 0.34 cfs @ 12.13 hrs, Volume= 1,122 cf, Depth= 6.11" Routed to Pond 11 : Surface 11Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 611 98 Site Impervious1,593 80 >75% Grass cover, Good, HSG D2,204 85 Weighted Average1,593 72.28% Pervious Area611 27.72% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR11: Basin 11RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=2,204 sfRunoff Volume=1,122 cfRunoff Depth=6.11"Tc=6.0 minCN=850.34 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 266HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR12: West site to Area DrainRunoff = 0.36 cfs @ 12.13 hrs, Volume= 1,147 cf, Depth= 5.52" Routed to Link 33L : On-site Closed DrainageRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 34 98 Site Impervious2,459 80 >75% Grass cover, Good, HSG D2,493 80 Weighted Average2,459 98.64% Pervious Area34 1.36% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR12: West site to Area DrainRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=2,493 sfRunoff Volume=1,147 cfRunoff Depth=5.52"Tc=6.0 minCN=800.36 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 267HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR13: Pavers frontRunoff = 0.03 cfs @ 20.97 hrs, Volume= 1,141 cf, Depth= 5.76" Routed to Pond PS : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 28 98 Site Impervious* 248 98 Permeable Pavers2,103 80 >75% Grass cover, Good, HSG D2,379 82 Weighted Average2,103 88.40% Pervious Area276 11.60% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR13: Pavers frontRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=2,379 sfRunoff Volume=1,141 cfRunoff Depth=5.76"Tc=674.0 minCN=820.03 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 268HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR14: Pavers NorthRunoff = 0.01 cfs @ 20.23 hrs, Volume= 404 cf, Depth= 7.17" Routed to Pond PN : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 60 98 Site Impervious* 464 98 Porous Pavers152 80 >75% Grass cover, Good, HSG D676 94 Weighted Average152 22.49% Pervious Area524 77.51% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Pavers TcSubcatchment PR14: Pavers NorthRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0090.0090.0080.0080.0070.0070.0060.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=676 sfRunoff Volume=404 cfRunoff Depth=7.17"Tc=674.0 minCN=940.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 269HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15a: Roof WestRunoff = 0.48 cfs @ 12.13 hrs, Volume= 1,753 cf, Depth= 7.65" Routed to Pond 31P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 2,750 98 Roof2,750 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15a: Roof WestRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.50.450.40.350.30.250.20.150.10.050NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=2,750 sfRunoff Volume=1,753 cfRunoff Depth=7.65"Tc=6.0 minCN=980.48 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 270HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR15b: Roof EastRunoff = 0.50 cfs @ 12.13 hrs, Volume= 1,842 cf, Depth= 7.65" Routed to Pond 33P : Distribution PipesRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 2,889 98 Roof2,889 100.00% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR15b: Roof EastRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.550.50.450.40.350.30.250.20.150.10.050NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=2,889 sfRunoff Volume=1,842 cfRunoff Depth=7.65"Tc=6.0 minCN=980.50 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 271HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR16: Remainder of siteRunoff = 2.22 cfs @ 12.13 hrs, Volume= 7,373 cf, Depth= 6.46" Routed to Reach DP-PR : Proposed SiteRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 6,144 98 Site Impervious7,550 80 >75% Grass cover, Good, HSG D13,694 88 Weighted Average7,550 55.13% Pervious Area6,144 44.87% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR16: Remainder of siteRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)210NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=13,694 sfRunoff Volume=7,373 cfRunoff Depth=6.46"Tc=6.0 minCN=882.22 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 272HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR17: Pavers pathRunoff = 0.01 cfs @ 20.97 hrs, Volume= 230 cf, Depth= 6.22" Routed to Pond 30P : Porous PaversRunoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 150 98 Permeable Pavers293 80 >75% Grass cover, Good, HSG D443 86 Weighted Average293 66.14% Pervious Area150 33.86% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)674.0Direct Entry, Paver TcSubcatchment PR17: Pavers pathRunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=443 sfRunoff Volume=230 cfRunoff Depth=6.22"Tc=674.0 minCN=860.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 273HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR2: Basin 2Runoff = 0.02 cfs @ 12.13 hrs, Volume= 75 cf, Depth= 5.52" Routed to Pond 2 : Surface 2Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description164 80 >75% Grass cover, Good, HSG D164 100.00% Pervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR2: Basin 2RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=164 sfRunoff Volume=75 cfRunoff Depth=5.52"Tc=6.0 minCN=800.02 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 274HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR3: Basin 3Runoff = 0.06 cfs @ 12.13 hrs, Volume= 205 cf, Depth= 5.64" Routed to Pond 3 : Surface 3Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 14 98 Site Impervious423 80 >75% Grass cover, Good, HSG D437 81 Weighted Average423 96.80% Pervious Area14 3.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR3: Basin 3RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=437 sfRunoff Volume=205 cfRunoff Depth=5.64"Tc=6.0 minCN=810.06 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 275HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR4: Basin 4Runoff = 0.38 cfs @ 12.13 hrs, Volume= 1,211 cf, Depth= 5.76" Routed to Pond 4 : Surface 4Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 253 98 Impervious2,272 80 >75% Grass cover, Good, HSG D2,525 82 Weighted Average2,272 89.98% Pervious Area253 10.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR4: Basin 4RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=2,525 sfRunoff Volume=1,211 cfRunoff Depth=5.76"Tc=6.0 minCN=820.38 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 276HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR5: Basin 5Runoff = 0.03 cfs @ 12.13 hrs, Volume= 84 cf, Depth= 5.87" Routed to Pond 5 : Surface 5Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 31 98 Site Impervious141 80 >75% Grass cover, Good, HSG D172 83 Weighted Average141 81.98% Pervious Area31 18.02% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR5: Basin 5RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=172 sfRunoff Volume=84 cfRunoff Depth=5.87"Tc=6.0 minCN=830.03 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 277HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR6: Basin 6Runoff = 0.03 cfs @ 12.13 hrs, Volume= 96 cf, Depth= 6.11" Routed to Pond 6 : Surface 6Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 57 98 Site Impervious131 80 >75% Grass cover, Good, HSG D188 85 Weighted Average131 69.68% Pervious Area57 30.32% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR6: Basin 6RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=188 sfRunoff Volume=96 cfRunoff Depth=6.11"Tc=6.0 minCN=850.03 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 278HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR7: Basin 7Runoff = 0.07 cfs @ 12.13 hrs, Volume= 233 cf, Depth= 6.11" Routed to Pond 7 : Surface 7Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 120 98 Site Impervious338 80 >75% Grass cover, Good, HSG D458 85 Weighted Average338 73.80% Pervious Area120 26.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR7: Basin 7RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=458 sfRunoff Volume=233 cfRunoff Depth=6.11"Tc=6.0 minCN=850.07 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 279HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR8: Basin 8Runoff = 0.09 cfs @ 12.13 hrs, Volume= 302 cf, Depth= 5.76" Routed to Pond 8 : Surface 8Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 64 98 Site Impervious566 80 >75% Grass cover, Good, HSG D630 82 Weighted Average566 89.84% Pervious Area64 10.16% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR8: Basin 8RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.1050.10.0950.090.0850.080.0750.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=630 sfRunoff Volume=302 cfRunoff Depth=5.76"Tc=6.0 minCN=820.09 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 280HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Subcatchment PR9: Basin 9Runoff = 0.61 cfs @ 12.13 hrs, Volume= 1,997 cf, Depth= 6.11" Routed to Pond 9 : Surface 9Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsNOAA 24-hr D 100-YR Rainfall=7.89"Area (sf) CN Description* 1,067 98 Impervious2,856 80 >75% Grass cover, Good, HSG D3,923 85 Weighted Average2,856 72.80% Pervious Area1,067 27.20% Impervious AreaTc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)6.0Direct Entry, Min TcSubcatchment PR9: Basin 9RunoffHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.650.60.550.50.450.40.350.30.250.20.150.10.050NOAA 24-hr D100-YR Rainfall=7.89"Runoff Area=3,923 sfRunoff Volume=1,997 cfRunoff Depth=6.11"Tc=6.0 minCN=850.61 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 281HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach DP-PR: Proposed Site[40] Hint: Not Described (Outflow=Inflow)Inflow Area = 41,329 sf, 38.60% Impervious, Inflow Depth = 6.34" for 100-YR eventInflow = 5.54 cfs @ 12.14 hrs, Volume= 21,821 cfOutflow = 5.54 cfs @ 12.14 hrs, Volume= 21,821 cf, Atten= 0%, Lag= 0.0 minRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Reach DP-PR: Proposed SiteInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)6543210Inflow Area=41,329 sf5.54 cfs5.54 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 282HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P1: 4" Pipe Under Path[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 6.07" for 100-YR eventInflow = 0.35 cfs @ 12.16 hrs, Volume= 1,275 cfOutflow = 0.35 cfs @ 12.16 hrs, Volume= 1,275 cf, Atten= 0%, Lag= 0.0 min Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 6.09 fps, Min. Travel Time= 0.0 minAvg. Velocity = 2.03 fps, Avg. Travel Time= 0.1 minPeak Storage= 1 cf @ 12.16 hrsAverage Depth at Peak Storage= 0.17' , Surface Width= 0.47'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.45 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 15.0' Slope= 0.0667 '/'Inlet Invert= 177.18', Outlet Invert= 176.18' NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 283HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P1: 4" Pipe Under PathInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfAvg. Flow Depth=0.17'Max Vel=6.09 fps6.0"Round Pipen=0.013L=15.0'S=0.0667 '/'Capacity=1.45 cfs0.35 cfs0.35 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 284HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P2: 8" Pipe[52] Hint: Inlet/Outlet conditions not evaluatedInflow Area = 6,492 sf, 18.21% Impervious, Inflow Depth = 5.91" for 100-YR eventInflow = 0.77 cfs @ 12.20 hrs, Volume= 3,199 cfOutflow = 0.77 cfs @ 12.20 hrs, Volume= 3,199 cf, Atten= 0%, Lag= 0.3 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 4.05 fps, Min. Travel Time= 0.3 minAvg. Velocity = 1.31 fps, Avg. Travel Time= 0.8 minPeak Storage= 12 cf @ 12.20 hrsAverage Depth at Peak Storage= 0.36' , Surface Width= 0.66'Bank-Full Depth= 0.67' Flow Area= 0.3 sf, Capacity= 1.37 cfs8.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 65.0' Slope= 0.0129 '/'Inlet Invert= 174.50', Outlet Invert= 173.66' NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 285HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P2: 8" PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.850.80.750.70.650.60.550.50.450.40.350.30.250.20.150.10.050Inflow Area=6,492 sfAvg. Flow Depth=0.36'Max Vel=4.05 fps8.0"Round Pipen=0.013L=65.0'S=0.0129 '/'Capacity=1.37 cfs0.77 cfs0.77 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 286HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Reach P3: 4" Outlet Pipe[52] Hint: Inlet/Outlet conditions not evaluated[80] Warning: Exceeded Pond 11S by 0.01' @ 12.12 hrs (0.02 cfs 5 cf) Inflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 6.35" for 100-YR eventInflow = 0.33 cfs @ 12.14 hrs, Volume= 1,524 cfOutflow = 0.33 cfs @ 12.14 hrs, Volume= 1,524 cf, Atten= 0%, Lag= 0.2 min Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Max. Velocity= 6.24 fps, Min. Travel Time= 0.4 minAvg. Velocity = 1.68 fps, Avg. Travel Time= 1.3 minPeak Storage= 7 cf @ 12.14 hrsAverage Depth at Peak Storage= 0.16' , Surface Width= 0.46'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 1.53 cfs6.0" Round Pipen= 0.013 Corrugated PE, smooth interiorLength= 136.0' Slope= 0.0748 '/'Inlet Invert= 183.17', Outlet Invert= 173.00' NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 287HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCReach P3: 4" Outlet PipeInflowOutflowHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,880 sfAvg. Flow Depth=0.16'Max Vel=6.24 fps6.0"Round Pipen=0.013L=136.0'S=0.0748 '/'Capacity=1.53 cfs0.33 cfs0.33 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 288HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1: Surface 1Inflow Area = 1,918 sf, 33.52% Impervious, Inflow Depth = 6.22" for 100-YR eventInflow = 0.30 cfs @ 12.13 hrs, Volume= 995 cfOutflow = 0.30 cfs @ 12.14 hrs, Volume= 995 cf, Atten= 1%, Lag= 0.6 minPrimary = 0.29 cfs @ 12.14 hrs, Volume= 858 cf Routed to Pond 2 : Surface 2Secondary = 0.00 cfs @ 12.14 hrs, Volume= 137 cf Routed to Pond 1S : Subsurface 1Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.45' @ 12.14 hrs Surf.Area= 51 sf Storage= 20 cfPlug-Flow detention time= 6.7 min calculated for 995 cf (100% of inflow)Center-of-Mass det. time= 6.7 min ( 800.2 - 793.5 )Volume Invert Avail.Storage Storage Description#1 182.50' 23 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 2 0 0183.00 17 5 5183.51 55 18 23Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.29 cfs @ 12.14 hrs HW=183.45' TW=182.00' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.17 cfs @ 2.74 fps)4=Orifice/Grate (Orifice Controls 0.12 cfs @ 1.45 fps)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=183.45' TW=178.24' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 289HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1: Surface 1InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=1,918 sfPeak Elev=183.45'Storage=20 cf0.30 cfs0.30 cfs0.29 cfs0.00 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 290HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 1S: Subsurface 1[90] Warning: Qout>Qin may require smaller dt or Finer RoutingInflow = 0.00 cfs @ 12.14 hrs, Volume= 137 cfOutflow = 0.02 cfs @ 12.20 hrs, Volume= 136 cf, Atten= 0%, Lag= 3.9 minPrimary = 0.02 cfs @ 12.20 hrs, Volume= 136 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.28' @ 12.19 hrs Surf.Area= 52 sf Storage= 3 cfPlug-Flow detention time= 7.6 min calculated for 136 cf (100% of inflow)Center-of-Mass det. time= 6.5 min ( 893.6 - 887.1 )Volume Invert Avail.Storage Storage Description#1 178.16' 48 cfCustom Stage Data (Prismatic) Listed below (Recalc)122 cf Overall - 1 cf Embedded = 121 cf x 40.0% Voids#2 178.17' 1 cf4.0" Round Pipe Storage Inside #1L= 11.8'49 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.16 52 0 0180.50 52 122 122Device Routing Invert Outlet Devices#1 Primary 178.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.20 hrs HW=178.26' TW=178.22' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 0.94 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 291HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 1S: Subsurface 1InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=178.28'Storage=3 cf0.00 cfs0.02 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 292HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2: Surface 2Inflow Area = 2,082 sf, 30.88% Impervious, Inflow Depth = 5.38" for 100-YR eventInflow = 0.32 cfs @ 12.14 hrs, Volume= 934 cfOutflow = 0.32 cfs @ 12.14 hrs, Volume= 934 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routed to Pond 3 : Surface 3Secondary = 0.32 cfs @ 12.14 hrs, Volume= 934 cf Routed to Pond 2S : Subsurface 2Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.00' @ 0.00 hrs Surf.Area= 2 sf Storage= 0 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= (not calculated: outflow precedes inflow)Volume Invert Avail.Storage Storage Description#1 182.00' 28 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 25 7 7183.01 60 22 28Device Routing Invert Outlet Devices#1 Secondary 182.00'4.00 cfs Exfiltration at all elevations #2 Primary 183.00'8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=182.00' TW=181.50' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate ( Controls 0.00 cfs)4=Orifice/Grate ( Controls 0.00 cfs)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=182.00' TW=178.36' (Dynamic Tailwater)1=Exfiltration (Passes 0.00 cfs of 4.00 cfs potential flow) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 293HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2: Surface 2InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,082 sfPeak Elev=182.00'Storage=0 cf0.32 cfs0.32 cfs0.00 cfs0.32 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 294HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 2S: Subsurface 2[80] Warning: Exceeded Pond 1S by 0.13' @ 12.15 hrs (0.09 cfs 19 cf) Inflow = 0.32 cfs @ 12.14 hrs, Volume= 1,070 cfOutflow = 0.31 cfs @ 12.15 hrs, Volume= 1,070 cf, Atten= 3%, Lag= 0.7 minPrimary = 0.31 cfs @ 12.15 hrs, Volume= 1,070 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.38' @ 12.16 hrs Surf.Area= 57 sf Storage= 17 cfPlug-Flow detention time= 2.1 min calculated for 1,070 cf (100% of inflow)Center-of-Mass det. time= 2.0 min ( 803.6 - 801.7 )Volume Invert Avail.Storage Storage Description#1 177.66' 53 cfCustom Stage Data (Prismatic) Listed below (Recalc)133 cf Overall - 1 cf Embedded = 133 cf x 40.0% Voids#2 177.67' 1 cf4.0" Round Pipe Storage Inside #1L= 10.0'54 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.66 57 0 0180.00 57 133 133Device Routing Invert Outlet Devices#1 Primary 177.67'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.31 cfs @ 12.15 hrs HW=178.37' TW=177.83' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.31 cfs @ 3.53 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 295HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 2S: Subsurface 2InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Peak Elev=178.38'Storage=17 cf0.32 cfs0.31 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 296HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3: Surface 3Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 0.98" for 100-YR eventInflow = 0.06 cfs @ 12.13 hrs, Volume= 205 cfOutflow = 0.06 cfs @ 12.14 hrs, Volume= 205 cf, Atten= 0%, Lag= 0.4 minPrimary = 0.06 cfs @ 12.14 hrs, Volume= 77 cf Routed to Reach P1 : 4" Pipe Under PathSecondary = 0.00 cfs @ 12.14 hrs, Volume= 128 cf Routed to Pond 3S : Subsurface 3Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.83' @ 12.14 hrs Surf.Area= 52 sf Storage= 11 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 11.8 min ( 819.6 - 807.7 )Volume Invert Avail.Storage Storage Description#1 181.50' 22 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 15 0 0182.00 71 22 22Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 181.80'12inch-Dome Grate Capacity Primary OutFlow Max=0.06 cfs @ 12.14 hrs HW=181.83' TW=177.34' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.06 cfs)Secondary OutFlow Max=0.00 cfs @ 12.14 hrs HW=181.83' TW=177.79' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.00 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 297HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3: Surface 3InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.070.0650.060.0550.050.0450.040.0350.030.0250.020.0150.010.0050Inflow Area=2,519 sfPeak Elev=181.83'Storage=11 cf0.06 cfs0.06 cfs0.06 cfs0.00 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 298HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 3S: Subsurface 3Inflow = 0.31 cfs @ 12.15 hrs, Volume= 1,198 cfOutflow = 0.30 cfs @ 12.18 hrs, Volume= 1,198 cf, Atten= 4%, Lag= 1.4 minPrimary = 0.30 cfs @ 12.18 hrs, Volume= 1,198 cf Routed to Reach P1 : 4" Pipe Under PathRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.86' @ 12.17 hrs Surf.Area= 71 sf Storage= 21 cfPlug-Flow detention time= 2.5 min calculated for 1,198 cf (100% of inflow)Center-of-Mass det. time= 2.4 min ( 813.3 - 810.9 )Volume Invert Avail.Storage Storage Description#1 177.17' 66 cfCustom Stage Data (Prismatic) Listed below (Recalc)165 cf Overall - 1 cf Embedded = 164 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'67 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 71 0 0179.50 71 165 165Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.30 cfs @ 12.18 hrs HW=177.86' TW=177.35' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.30 cfs @ 3.45 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 299HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 3S: Subsurface 3InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Peak Elev=177.86'Storage=21 cf0.31 cfs0.30 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 300HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4: Surface 4Inflow Area = 2,525 sf, 10.02% Impervious, Inflow Depth = 5.76" for 100-YR eventInflow = 0.38 cfs @ 12.13 hrs, Volume= 1,211 cfOutflow = 0.33 cfs @ 12.16 hrs, Volume= 1,211 cf, Atten= 11%, Lag= 2.0 minPrimary = 0.31 cfs @ 12.16 hrs, Volume= 651 cf Routed to Pond 5 : Surface 5Secondary = 0.02 cfs @ 12.16 hrs, Volume= 561 cf Routed to Pond 4S : Subsurface 4Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.47' @ 12.16 hrs Surf.Area= 220 sf Storage= 110 cfPlug-Flow detention time= 21.2 min calculated for 1,211 cf (100% of inflow)Center-of-Mass det. time= 21.2 min ( 826.3 - 805.0 )Volume Invert Avail.Storage Storage Description#1 182.50' 119 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.50 14 0 0183.00 114 32 32183.51 229 87 119Device Routing Invert Outlet Devices#1 Secondary 182.50'4.000 in/hr Exfiltration over Surface area #2 Primary 183.50'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 183.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 183.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.31 cfs @ 12.16 hrs HW=183.47' TW=182.98' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.18 cfs @ 2.81 fps)4=Orifice/Grate (Orifice Controls 0.14 cfs @ 1.50 fps)Secondary OutFlow Max=0.02 cfs @ 12.16 hrs HW=183.47' TW=178.27' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.02 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 301HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4: Surface 4InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,525 sfPeak Elev=183.47'Storage=110 cf0.38 cfs0.33 cfs0.31 cfs0.02 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 302HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 4S: Subsurface 4Inflow = 0.02 cfs @ 12.16 hrs, Volume= 561 cfOutflow = 0.02 cfs @ 12.21 hrs, Volume= 560 cf, Atten= 4%, Lag= 3.1 minPrimary = 0.02 cfs @ 12.21 hrs, Volume= 560 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 178.27' @ 12.21 hrs Surf.Area= 229 sf Storage= 10 cfPlug-Flow detention time= 13.3 min calculated for 560 cf (100% of inflow)Center-of-Mass det. time= 12.3 min ( 932.5 - 920.2 )Volume Invert Avail.Storage Storage Description#1 178.17' 212 cfCustom Stage Data (Prismatic) Listed below (Recalc)534 cf Overall - 3 cf Embedded = 530 cf x 40.0% Voids#2 178.18' 3 cf4.0" Round Pipe Storage Inside #1L= 36.0'215 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)178.17 229 0 0180.50 229 534 534Device Routing Invert Outlet Devices#1 Primary 178.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.21 hrs HW=178.27' TW=177.78' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 1.02 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 303HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 4S: Subsurface 4InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0220.0210.020.0190.0180.0170.0160.0150.0140.0130.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=178.27'Storage=10 cf0.02 cfs0.02 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 304HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5: Surface 5Inflow Area = 2,697 sf, 10.53% Impervious, Inflow Depth = 3.27" for 100-YR eventInflow = 0.34 cfs @ 12.16 hrs, Volume= 735 cfOutflow = 0.33 cfs @ 12.17 hrs, Volume= 735 cf, Atten= 2%, Lag= 0.9 minPrimary = 0.33 cfs @ 12.17 hrs, Volume= 632 cf Routed to Pond 6 : Surface 6Secondary = 0.01 cfs @ 12.17 hrs, Volume= 102 cf Routed to Pond 5S : Subsurface 5Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.98' @ 12.17 hrs Surf.Area= 66 sf Storage= 34 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 6.3 min ( 758.1 - 751.9 )Volume Invert Avail.Storage Storage Description#1 182.00' 36 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)182.00 2 0 0182.50 36 10 10183.01 68 27 36Device Routing Invert Outlet Devices#1 Secondary 182.00'4.000 in/hr Exfiltration over Surface area #2 Primary 183.00'7.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.50'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.75'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.33 cfs @ 12.17 hrs HW=182.98' TW=182.49' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.18 cfs @ 2.85 fps)4=Orifice/Grate (Orifice Controls 0.15 cfs @ 1.54 fps)Secondary OutFlow Max=0.01 cfs @ 12.17 hrs HW=182.98' TW=177.78' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 305HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5: Surface 5InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,697 sfPeak Elev=182.98'Storage=34 cf0.34 cfs0.33 cfs0.33 cfs0.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 306HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 5S: Subsurface 5Inflow = 0.03 cfs @ 12.20 hrs, Volume= 662 cfOutflow = 0.03 cfs @ 12.22 hrs, Volume= 662 cf, Atten= 0%, Lag= 1.1 minPrimary = 0.03 cfs @ 12.22 hrs, Volume= 662 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.78' @ 12.22 hrs Surf.Area= 68 sf Storage= 3 cfPlug-Flow detention time= 3.7 min calculated for 662 cf (100% of inflow)Center-of-Mass det. time= 3.3 min ( 923.3 - 920.0 )Volume Invert Avail.Storage Storage Description#1 177.67' 63 cfCustom Stage Data (Prismatic) Listed below (Recalc)158 cf Overall - 1 cf Embedded = 157 cf x 40.0% Voids#2 177.68' 1 cf4.0" Round Pipe Storage Inside #1L= 12.0'64 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.67 68 0 0180.00 68 158 158Device Routing Invert Outlet Devices#1 Primary 177.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.03 cfs @ 12.22 hrs HW=177.78' TW=177.30' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.03 cfs @ 1.10 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 307HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 5S: Subsurface 5InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Peak Elev=177.78'Storage=3 cf0.03 cfs0.03 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 308HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6: Surface 6Inflow Area = 2,885 sf, 11.82% Impervious, Inflow Depth = 3.03" for 100-YR eventInflow = 0.35 cfs @ 12.17 hrs, Volume= 728 cfOutflow = 0.35 cfs @ 12.18 hrs, Volume= 728 cf, Atten= 1%, Lag= 0.8 minPrimary = 0.34 cfs @ 12.18 hrs, Volume= 628 cf Routed to Pond 7 : Surface 7Secondary = 0.01 cfs @ 12.18 hrs, Volume= 100 cf Routed to Pond 6S : Subsurface 6Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 182.49' @ 12.18 hrs Surf.Area= 62 sf Storage= 36 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 6.0 min ( 756.0 - 750.0 )Volume Invert Avail.Storage Storage Description#1 181.50' 37 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)181.50 2 0 0182.00 40 11 11182.51 63 26 37Device Routing Invert Outlet Devices#1 Secondary 181.50'4.000 in/hr Exfiltration over Surface area #2 Primary 182.50'9.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 182.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 182.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.34 cfs @ 12.18 hrs HW=182.49' TW=181.51' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)3=Orifice/Grate (Orifice Controls 0.18 cfs @ 2.90 fps)4=Orifice/Grate (Orifice Controls 0.16 cfs @ 1.58 fps)Secondary OutFlow Max=0.01 cfs @ 12.18 hrs HW=182.49' TW=177.29' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 309HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6: Surface 6InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,885 sfPeak Elev=182.49'Storage=36 cf0.35 cfs0.35 cfs0.34 cfs0.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 310HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 6S: Subsurface 6Inflow = 0.03 cfs @ 12.21 hrs, Volume= 762 cfOutflow = 0.03 cfs @ 12.23 hrs, Volume= 761 cf, Atten= 0%, Lag= 1.0 minPrimary = 0.03 cfs @ 12.23 hrs, Volume= 761 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.30' @ 12.23 hrs Surf.Area= 63 sf Storage= 3 cfPlug-Flow detention time= 3.2 min calculated for 761 cf (100% of inflow)Center-of-Mass det. time= 2.9 min ( 915.5 - 912.6 )Volume Invert Avail.Storage Storage Description#1 177.17' 58 cfCustom Stage Data (Prismatic) Listed below (Recalc)147 cf Overall - 1 cf Embedded = 146 cf x 40.0% Voids#2 177.18' 1 cf4.0" Round Pipe Storage Inside #1L= 13.0'59 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)177.17 63 0 0179.50 63 147 147Device Routing Invert Outlet Devices#1 Primary 177.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.03 cfs @ 12.23 hrs HW=177.30' TW=177.08' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.03 cfs @ 1.16 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 311HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 6S: Subsurface 6InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0340.0320.030.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Peak Elev=177.30'Storage=3 cf0.03 cfs0.03 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 312HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7: Surface 7Inflow Area = 3,343 sf, 13.79% Impervious, Inflow Depth = 3.09" for 100-YR eventInflow = 0.40 cfs @ 12.17 hrs, Volume= 861 cfOutflow = 0.39 cfs @ 12.18 hrs, Volume= 861 cf, Atten= 0%, Lag= 0.7 minPrimary = 0.38 cfs @ 12.18 hrs, Volume= 680 cf Routed to Pond 8 : Surface 8Secondary = 0.01 cfs @ 12.18 hrs, Volume= 181 cf Routed to Pond 7S : Subsurface 7Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 181.51' @ 12.18 hrs Surf.Area= 117 sf Storage= 68 cfPlug-Flow detention time= 13.4 min calculated for 861 cf (100% of inflow)Center-of-Mass det. time= 13.4 min ( 770.4 - 757.0 )Volume Invert Avail.Storage Storage Description#1 180.00' 69 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)180.00 2 0 0180.50 18 5 5181.00 58 19 24181.51 117 45 69Device Routing Invert Outlet Devices#1 Secondary 180.00'4.000 in/hr Exfiltration over Surface area #2 Primary 181.50'10.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Primary 181.00'3.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 181.25'5.0" W x 3.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.38 cfs @ 12.18 hrs HW=181.51' TW=180.13' (Dynamic Tailwater)2=Sharp-Crested Rectangular Weir (Weir Controls 0.02 cfs @ 0.28 fps)3=Orifice/Grate (Orifice Controls 0.19 cfs @ 2.96 fps)4=Orifice/Grate (Orifice Controls 0.17 cfs @ 1.67 fps)Secondary OutFlow Max=0.01 cfs @ 12.18 hrs HW=181.51' TW=177.09' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 313HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7: Surface 7InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.440.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=3,343 sfPeak Elev=181.51'Storage=68 cf0.40 cfs0.39 cfs0.38 cfs0.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 314HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 7S: Subsurface 7[62] Hint: Exceeded Reach P1 OUTLET depth by 0.77' @ 12.21 hrsInflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 10.57" for 100-YR eventInflow = 0.39 cfs @ 12.16 hrs, Volume= 2,218 cfOutflow = 0.37 cfs @ 12.20 hrs, Volume= 2,217 cf, Atten= 7%, Lag= 2.4 minPrimary = 0.37 cfs @ 12.20 hrs, Volume= 2,217 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 177.11' @ 12.20 hrs Surf.Area= 117 sf Storage= 45 cfPlug-Flow detention time= 3.2 min calculated for 2,217 cf (100% of inflow)Center-of-Mass det. time= 3.1 min ( 853.7 - 850.6 )Volume Invert Avail.Storage Storage Description#1 176.17' 108 cfCustom Stage Data (Prismatic) Listed below (Recalc)273 cf Overall - 2 cf Embedded = 271 cf x 40.0% Voids#2 176.18' 2 cf4.0" Round Pipe Storage Inside #1L= 21.0'110 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)176.17 117 0 0178.50 117 273 273Device Routing Invert Outlet Devices#1 Primary 176.18'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.37 cfs @ 12.20 hrs HW=177.11' TW=175.55' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.37 cfs @ 4.21 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 315HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 7S: Subsurface 7InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.440.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfPeak Elev=177.11'Storage=45 cf0.39 cfs0.37 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 316HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8: Surface 8Inflow Area = 3,973 sf, 13.21% Impervious, Inflow Depth = 2.97" for 100-YR eventInflow = 0.45 cfs @ 12.18 hrs, Volume= 982 cfOutflow = 0.45 cfs @ 12.19 hrs, Volume= 982 cf, Atten= 1%, Lag= 0.5 minPrimary = 0.43 cfs @ 12.19 hrs, Volume= 670 cf Routed to Reach P2 : 8" PipeSecondary = 0.02 cfs @ 12.19 hrs, Volume= 312 cf Routed to Pond 8S : Subsurface 8Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 180.13' @ 12.19 hrs Surf.Area= 172 sf Storage= 90 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 18.7 min ( 780.6 - 761.9 )Volume Invert Avail.Storage Storage Description#1 179.00' 164 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)179.00 7 0 0179.50 49 14 14179.75 120 21 35180.50 223 129 164Device Routing Invert Outlet Devices#1 Secondary 179.00'4.000 in/hr Exfiltration over Surface area #2 Primary 180.00'12inch-Dome Grate Capacity Primary OutFlow Max=0.43 cfs @ 12.19 hrs HW=180.13' TW=174.86' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.43 cfs)Secondary OutFlow Max=0.02 cfs @ 12.19 hrs HW=180.13' TW=175.51' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.02 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 317HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8: Surface 8InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.50.450.40.350.30.250.20.150.10.050Inflow Area=3,973 sfPeak Elev=180.13'Storage=90 cf0.45 cfs0.45 cfs0.43 cfs0.02 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 318HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 8S: Subsurface 8Inflow Area = 2,519 sf, 26.08% Impervious, Inflow Depth = 12.05" for 100-YR eventInflow = 0.38 cfs @ 12.20 hrs, Volume= 2,529 cfOutflow = 0.37 cfs @ 12.25 hrs, Volume= 2,528 cf, Atten= 5%, Lag= 2.6 minPrimary = 0.37 cfs @ 12.25 hrs, Volume= 2,528 cf Routed to Reach P2 : 8" PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 175.61' @ 12.24 hrs Surf.Area= 120 sf Storage= 46 cfPlug-Flow detention time= 3.4 min calculated for 2,528 cf (100% of inflow)Center-of-Mass det. time= 3.0 min ( 858.2 - 855.2 )Volume Invert Avail.Storage Storage Description#1 174.67' 111 cfCustom Stage Data (Prismatic) Listed below (Recalc)280 cf Overall - 2 cf Embedded = 278 cf x 40.0% Voids#2 174.68' 2 cf4.0" Round Pipe Storage Inside #1L= 24.0'113 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.67 120 0 0177.00 120 280 280Device Routing Invert Outlet Devices#1 Primary 174.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.37 cfs @ 12.25 hrs HW=175.60' TW=174.85' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.37 cfs @ 4.19 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 319HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 8S: Subsurface 8InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.420.40.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,519 sfPeak Elev=175.61'Storage=46 cf0.38 cfs0.37 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 320HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9: Surface 9Inflow Area = 3,923 sf, 27.20% Impervious, Inflow Depth = 6.11" for 100-YR eventInflow = 0.61 cfs @ 12.13 hrs, Volume= 1,997 cfOutflow = 0.61 cfs @ 12.13 hrs, Volume= 1,997 cf, Atten= 0%, Lag= 0.2 minPrimary = 0.60 cfs @ 12.13 hrs, Volume= 1,709 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.13 hrs, Volume= 288 cf Routed to Pond 9S : Subsurface 9Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.41' @ 12.13 hrs Surf.Area= 70 sf Storage= 14 cfPlug-Flow detention time= 3.3 min calculated for 1,996 cf (100% of inflow)Center-of-Mass det. time= 3.4 min ( 799.8 - 796.5 )Volume Invert Avail.Storage Storage Description#1 174.00' 86 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.00 1 0 0175.00 170 86 86Device Routing Invert Outlet Devices#1 Primary 174.25'12inch-Dome Grate Capacity #2 Secondary 174.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.60 cfs @ 12.13 hrs HW=174.41' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.60 cfs)Secondary OutFlow Max=0.01 cfs @ 12.13 hrs HW=174.41' TW=170.73' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 321HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9: Surface 9InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.650.60.550.50.450.40.350.30.250.20.150.10.050Inflow Area=3,923 sfPeak Elev=174.41'Storage=14 cf0.61 cfs0.61 cfs0.60 cfs0.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 322HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 9S: Subsurface 9Inflow = 0.01 cfs @ 12.13 hrs, Volume= 288 cfOutflow = 0.01 cfs @ 12.21 hrs, Volume= 286 cf, Atten= 12%, Lag= 4.9 minPrimary = 0.01 cfs @ 12.21 hrs, Volume= 286 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 170.73' @ 12.21 hrs Surf.Area= 170 sf Storage= 10 cfPlug-Flow detention time= 37.2 min calculated for 286 cf (99% of inflow)Center-of-Mass det. time= 34.0 min ( 922.5 - 888.6 )Volume Invert Avail.Storage Storage Description#1 170.67' 395 cfCustom Stage Data (Prismatic) Listed below (Recalc)396 cf Overall - 1 cf Embedded = 395 cf#2 170.68' 1 cf4.0" Round Pipe Storage Inside #1L= 17.0'396 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)170.67 170 0 0173.00 170 396 396Device Routing Invert Outlet Devices#1 Primary 170.68'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.21 hrs HW=170.73' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.74 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 323HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 9S: Subsurface 9InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0070.0070.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Peak Elev=170.73'Storage=10 cf0.01 cfs0.01 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 324HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10: Surface 10Inflow Area = 3,386 sf, 9.57% Impervious, Inflow Depth = 5.76" for 100-YR eventInflow = 0.51 cfs @ 12.13 hrs, Volume= 1,624 cfOutflow = 0.50 cfs @ 12.14 hrs, Volume= 1,624 cf, Atten= 0%, Lag= 0.4 minPrimary = 0.49 cfs @ 12.14 hrs, Volume= 1,051 cf Routed to Link 33L : On-site Closed DrainageSecondary = 0.01 cfs @ 12.14 hrs, Volume= 573 cf Routed to Pond 10S : Subsurface 10Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.39' @ 12.14 hrs Surf.Area= 125 sf Storage= 37 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 11.0 min ( 816.0 - 805.0 )Volume Invert Avail.Storage Storage Description#1 173.00' 142 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)173.00 68 0 0174.00 215 142 142Device Routing Invert Outlet Devices#1 Primary 173.25'12inch-Dome Grate Capacity #2 Secondary 173.00'4.000 in/hr Exfiltration over Surface area Primary OutFlow Max=0.49 cfs @ 12.14 hrs HW=173.39' TW=0.00' (Dynamic Tailwater)1=12inch-Dome Grate Capacity (Custom Controls 0.49 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=173.39' TW=168.74' (Dynamic Tailwater)2=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 325HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10: Surface 10InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.550.50.450.40.350.30.250.20.150.10.050Inflow Area=3,386 sfPeak Elev=173.39'Storage=37 cf0.51 cfs0.50 cfs0.49 cfs0.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 326HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 10S: Subsurface 10Inflow = 0.01 cfs @ 12.14 hrs, Volume= 573 cfOutflow = 0.01 cfs @ 12.18 hrs, Volume= 572 cf, Atten= 2%, Lag= 2.4 minPrimary = 0.01 cfs @ 12.18 hrs, Volume= 572 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 168.74' @ 12.18 hrs Surf.Area= 215 sf Storage= 6 cfPlug-Flow detention time= 11.2 min calculated for 572 cf (100% of inflow)Center-of-Mass det. time= 10.2 min ( 948.1 - 937.8 )Volume Invert Avail.Storage Storage Description#1 168.67' 200 cfCustom Stage Data (Prismatic) Listed below (Recalc)501 cf Overall - 2 cf Embedded = 499 cf x 40.0% Voids#2 168.68' 2 cf4.0" Round Pipe Storage Inside #1L= 18.0'201 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)168.67 215 0 0171.00 215 501 501Device Routing Invert Outlet Devices#1 Primary 168.68'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 12.18 hrs HW=168.74' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.84 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 327HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 10S: Subsurface 10InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0120.0110.010.0090.0080.0070.0060.0050.0040.0030.0020.0010Peak Elev=168.74'Storage=6 cf0.01 cfs0.01 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 328HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11: Surface 11Inflow Area = 2,880 sf, 39.41% Impervious, Inflow Depth = 6.35" for 100-YR eventInflow = 0.34 cfs @ 12.13 hrs, Volume= 1,524 cfOutflow = 0.34 cfs @ 12.14 hrs, Volume= 1,524 cf, Atten= 0%, Lag= 0.4 minPrimary = 0.33 cfs @ 12.14 hrs, Volume= 777 cf Routed to Reach P3 : 4" Outlet PipeSecondary = 0.01 cfs @ 12.14 hrs, Volume= 747 cf Routed to Pond 11S : Subsurface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 185.41' @ 12.14 hrs Surf.Area= 119 sf Storage= 55 cfPlug-Flow detention time= (not calculated: outflow precedes inflow)Center-of-Mass det. time= 32.0 min ( 993.8 - 961.7 )Volume Invert Avail.Storage Storage Description#1 184.50' 284 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)184.50 23 0 0185.00 56 20 20186.00 211 134 153186.50 310 130 284Device Routing Invert Outlet Devices#1 Secondary 184.50'4.000 in/hr Exfiltration over Surface area #2 Primary 185.30'12inch-Dome Grate Capacity Primary OutFlow Max=0.33 cfs @ 12.14 hrs HW=185.41' TW=183.33' (Dynamic Tailwater)2=12inch-Dome Grate Capacity (Custom Controls 0.33 cfs)Secondary OutFlow Max=0.01 cfs @ 12.14 hrs HW=185.41' TW=183.32' (Dynamic Tailwater)1=Exfiltration (Exfiltration Controls 0.01 cfs) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 329HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11: Surface 11InflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.380.360.340.320.30.280.260.240.220.20.180.160.140.120.10.080.060.040.020Inflow Area=2,880 sfPeak Elev=185.41'Storage=55 cf0.34 cfs0.34 cfs0.33 cfs0.01 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 330HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 11S: Subsurface 11[90] Warning: Qout>Qin may require smaller dt or Finer RoutingInflow = 0.01 cfs @ 12.14 hrs, Volume= 747 cfOutflow = 0.02 cfs @ 12.22 hrs, Volume= 747 cf, Atten= 0%, Lag= 5.2 minPrimary = 0.02 cfs @ 12.22 hrs, Volume= 747 cf Routed to Reach P3 : 4" Outlet PipeRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 183.33' @ 12.17 hrs Surf.Area= 310 sf Storage= 19 cfPlug-Flow detention time= 18.2 min calculated for 747 cf (100% of inflow)Center-of-Mass det. time= 17.9 min ( 1,199.9 - 1,182.0 )Volume Invert Avail.Storage Storage Description#1 183.17' 289 cfCustom Stage Data (Prismatic) Listed below (Recalc)722 cf Overall x 40.0% VoidsElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)183.17 310 0 0185.50 310 722 722Device Routing Invert Outlet Devices#1 Primary 183.17'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.02 cfs @ 12.22 hrs HW=183.31' TW=183.30' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 0.64 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 331HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 11S: Subsurface 11InflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Peak Elev=183.33'Storage=19 cf0.01 cfs0.02 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 332HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 29P: Landscape FilterInflow Area = 5,639 sf,100.00% Impervious, Inflow Depth = 7.22" for 100-YR eventInflow = 0.59 cfs @ 12.13 hrs, Volume= 3,392 cfOutflow = 0.51 cfs @ 12.18 hrs, Volume= 3,388 cf, Atten= 13%, Lag= 3.4 minPrimary = 0.51 cfs @ 12.18 hrs, Volume= 3,388 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 171.05' @ 12.18 hrs Surf.Area= 1,000 sf Storage= 220 cfPlug-Flow detention time= 18.9 min calculated for 3,387 cf (100% of inflow)Center-of-Mass det. time= 18.3 min ( 761.5 - 743.1 )Volume Invert Avail.Storage Storage Description#1 170.50' 1,000 cfCustom Stage Data (Prismatic) Listed below (Recalc)Elevation Surf.Area Voids Inc.Store Cum.Store(feet) (sq-ft) (%) (cubic-feet) (cubic-feet)170.50 1,000 0.0 0 0170.51 1,000 40.0 4 4171.50 1,000 40.0 396 400171.51 1,000 20.0 2 402174.50 1,000 20.0 598 1,000Device Routing Invert Outlet Devices#1 Primary 170.51'6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.51 cfs @ 12.18 hrs HW=171.05' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.51 cfs @ 2.59 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 333HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 29P: Landscape FilterInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.650.60.550.50.450.40.350.30.250.20.150.10.050Inflow Area=5,639 sfPeak Elev=171.05'Storage=220 cf0.59 cfs0.51 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 334HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 30P: Porous PaversInflow Area = 443 sf, 33.86% Impervious, Inflow Depth = 6.22" for 100-YR eventInflow = 0.01 cfs @ 20.97 hrs, Volume= 230 cfOutflow = 0.01 cfs @ 21.00 hrs, Volume= 229 cf, Atten= 0%, Lag= 1.9 minPrimary = 0.01 cfs @ 21.00 hrs, Volume= 229 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.97' @ 21.00 hrs Surf.Area= 150 sf Storage= 3 cfPlug-Flow detention time= 17.8 min calculated for 229 cf (100% of inflow)Center-of-Mass det. time= 14.1 min ( 1,429.8 - 1,415.7 )Volume Invert Avail.Storage Storage Description#1 174.92' 135 cf31" section beneath paver (Prismatic) Listed below (Recalc)387 cf Overall - 2 cf Embedded = 385 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'137 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 150 0 0177.50 150 387 387Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.01 cfs @ 21.00 hrs HW=174.97' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.01 cfs @ 0.72 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 335HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond 30P: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Inflow Area=443 sfPeak Elev=174.97'Storage=3 cf0.01 cfs0.01 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 336HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 31P: Distribution Pipes[57] Hint: Peaked at 173.98' (Flood elevation advised)Inflow Area = 2,750 sf,100.00% Impervious, Inflow Depth = 7.65" for 100-YR eventInflow = 0.48 cfs @ 12.13 hrs, Volume= 1,753 cfOutflow = 0.48 cfs @ 12.13 hrs, Volume= 1,753 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.28 cfs @ 12.13 hrs, Volume= 1,653 cf Routed to Pond 29P : Landscape FilterSecondary = 0.20 cfs @ 12.13 hrs, Volume= 100 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 173.98' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'6.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.28 cfs @ 12.13 hrs HW=173.98' TW=171.02' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.28 cfs @ 3.19 fps)Secondary OutFlow Max=0.20 cfs @ 12.13 hrs HW=173.98' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.20 cfs @ 1.79 fps)Pond 31P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.50.450.40.350.30.250.20.150.10.050Inflow Area=2,750 sfPeak Elev=173.98'0.48 cfs0.48 cfs0.28 cfs0.20 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 337HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond 33P: Distribution Pipes[57] Hint: Peaked at 174.08' (Flood elevation advised)Inflow Area = 2,889 sf,100.00% Impervious, Inflow Depth = 7.65" for 100-YR eventInflow = 0.50 cfs @ 12.13 hrs, Volume= 1,842 cfOutflow = 0.50 cfs @ 12.13 hrs, Volume= 1,842 cf, Atten= 0%, Lag= 0.0 minPrimary = 0.31 cfs @ 12.13 hrs, Volume= 1,739 cf Routed to Pond 29P : Landscape FilterSecondary = 0.19 cfs @ 12.13 hrs, Volume= 103 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 174.08' @ 12.13 hrsDevice Routing Invert Outlet Devices#1 Secondary 173.70'4.0" Vert. Overflow C= 0.600 Limited to weir flow at low heads #2 Primary 173.37'4.0" Vert. Distribution Pipe C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.31 cfs @ 12.13 hrs HW=174.08' TW=171.02' (Dynamic Tailwater)2=Distribution Pipe (Orifice Controls 0.31 cfs @ 3.53 fps)Secondary OutFlow Max=0.19 cfs @ 12.13 hrs HW=174.08' TW=0.00' (Dynamic Tailwater)1=Overflow (Orifice Controls 0.19 cfs @ 2.20 fps)Pond 33P: Distribution PipesInflowOutflowPrimarySecondaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.550.50.450.40.350.30.250.20.150.10.050Inflow Area=2,889 sfPeak Elev=174.08'0.50 cfs0.50 cfs0.31 cfs0.19 cfs NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 338HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PN: Porous PaversInflow Area = 676 sf, 77.51% Impervious, Inflow Depth = 7.17" for 100-YR eventInflow = 0.01 cfs @ 20.23 hrs, Volume= 404 cfOutflow = 0.01 cfs @ 20.70 hrs, Volume= 402 cf, Atten= 0%, Lag= 28.5 minPrimary = 0.01 cfs @ 20.70 hrs, Volume= 402 cf Routed to Pond 11 : Surface 11Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 188.50' @ 20.70 hrs Surf.Area= 464 sf Storage= 13 cfPlug-Flow detention time= 42.4 min calculated for 402 cf (100% of inflow)Center-of-Mass det. time= 36.4 min ( 1,422.4 - 1,386.0 )Volume Invert Avail.Storage Storage Description#1 188.42' 417 cf31" section beneath pavers (Prismatic) Listed below (Recalc)1,197 cf Overall - 6 cf Embedded = 1,191 cf x 35.0% Voids#2 188.43' 6 cf4.0" Round Pipe Storage Inside #1L= 67.0'423 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)188.42 464 0 0191.00 464 1,197 1,197Device Routing Invert Outlet Devices#1 Primary 188.43'4.0" Round Culvert L= 7.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 188.43' / 186.00' S= 0.3471 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.09 sf Primary OutFlow Max=0.01 cfs @ 20.70 hrs HW=188.50' TW=185.30' (Dynamic Tailwater)1=Culvert (Inlet Controls 0.01 cfs @ 0.70 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 339HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PN: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0090.0090.0080.0080.0070.0070.0060.0060.0050.0050.0040.0040.0030.0030.0020.0020.0010.0010.0000Inflow Area=676 sfPeak Elev=188.50'Storage=13 cf4.0"Round Culvertn=0.013L=7.0'S=0.3471 '/'0.01 cfs0.01 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 340HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Pond PS: Porous PaversInflow Area = 2,379 sf, 11.60% Impervious, Inflow Depth = 5.76" for 100-YR eventInflow = 0.03 cfs @ 20.97 hrs, Volume= 1,141 cfOutflow = 0.03 cfs @ 21.02 hrs, Volume= 1,140 cf, Atten= 0%, Lag= 2.9 minPrimary = 0.03 cfs @ 21.02 hrs, Volume= 1,140 cf Routed to Link 33L : On-site Closed DrainageRouting by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.01 hrs / 3Peak Elev= 175.03' @ 21.02 hrs Surf.Area= 248 sf Storage= 10 cfPlug-Flow detention time= 11.0 min calculated for 1,140 cf (100% of inflow)Center-of-Mass det. time= 9.8 min ( 1,437.2 - 1,427.5 )Volume Invert Avail.Storage Storage Description#1 174.92' 223 cf31" section beneath paver (Prismatic) Listed below (Recalc)640 cf Overall - 2 cf Embedded = 637 cf x 35.0% Voids#2 174.93' 2 cf4.0" Round Pipe Storage Inside #1L= 28.0'226 cf Total Available StorageElevation Surf.Area Inc.Store Cum.Store(feet) (sq-ft) (cubic-feet) (cubic-feet)174.92 248 0 0177.50 248 640 640Device Routing Invert Outlet Devices#1 Primary 174.93'4.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.03 cfs @ 21.02 hrs HW=175.03' TW=0.00' (Dynamic Tailwater)1=Orifice/Grate (Orifice Controls 0.03 cfs @ 1.09 fps) NOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 341HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCPond PS: Porous PaversInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)0.0280.0260.0240.0220.020.0180.0160.0140.0120.010.0080.0060.0040.0020Inflow Area=2,379 sfPeak Elev=175.03'Storage=10 cf0.03 cfs0.03 cfsNOAA 24-hr D 100-YR Rainfall=7.89"15150_HydroCAD-10-25-2023 Printed 10/31/2023Prepared by Nitsch EngineeringPage 342HydroCAD® 10.10-7c s/n 00546 © 2022 HydroCAD Software Solutions LLCSummary for Link 33L: On-site Closed DrainageInflow Area = 27,635 sf, 35.49% Impervious, Inflow Depth = 6.27" for 100-YR eventInflow = 3.34 cfs @ 12.14 hrs, Volume= 14,448 cfPrimary = 3.34 cfs @ 12.14 hrs, Volume= 14,448 cf, Atten= 0%, Lag= 0.0 min Routed to Reach DP-PR : Proposed SitePrimary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.01 hrsLink 33L: On-site Closed DrainageInflowPrimaryHydrographTime (hours)10095908580757065605550454035302520151050Flow (cfs)3210Inflow Area=27,635 sf3.34 cfs3.34 cfs Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 15 APPENDIX D Closed Drainage System Design Smith College Lazarus-Wurtele Nitsch Project #15150 CMH 10/31/2023 Rainfall Details 25 year(s)Return Period........................................................................ Smith College Lazarus-Wurtele Nitsch Project #15150 CMH 10/31/2023 Subbasin Summary Subbasin Area Weighted Peak Time of Name Runoff Runoff Concentration Coefficient (ac)(cfs)(days hh:mm:ss) Sub-01 0.11 0.63 0.52 0 00:06:00 Sub-02 0.06 0.31 0.13 0 00:06:00 Smith College Lazarus-Wurtele Nitsch Project #15150 CMH 10/31/2023 Link Summary Pipe From Inlet To Outlet Pipe Pipe Pipe Manning's Peak Peak Flow Pipe Design Q/Qf Name (Inlet)Invert (Outlet)Invert Length Slope Diameter Roughness Flow Velocity Capacity Ratio Node Elevation Node Elevation Q Qf (ft)(ft)(ft)(%)(in)(cfs)(ft/sec)(cfs) Link-01 SiltPrison105 185.00 DMH200 180.00 150 3.34 12 0.0130 0.51 4.82 6.52 0.08 Link-02 DMH200 179.90 DMH202 179.50 63 0.63 12 0.0130 0.48 2.57 2.84 0.17 Link-03 DMH202 176.40 DMH203 173.00 93 3.66 12 0.0130 4.45 8.34 6.81 0.65 Link-04 DMH203 170.00 DMH206 169.00 27 3.70 12 0.0130 6.15 7.84 6.86 0.90 Link-05 DMH206 168.60 DMH204 168.10 70 0.71 12 0.0130 7.69 9.79 3.01 2.55 Link-07 DMH201 177.68 DMH202 176.80 18 5.03 12 0.0130 4.13 7.80 7.99 0.52 Link-08 AD105 173.00 DMH206 172.50 24 2.06 6 0.0130 0.46 3.66 0.80 0.57 Smith College Lazarus-Wurtele Nitsch Project #15150 CMH 10/31/2023 Junction Input Juntion Invert Rim Name Elevation Elevation (ft)(ft) AD105 173.00 177.30 DMH200 179.90 191.00 DMH201 177.68 183.50 DMH202 176.40 181.85 DMH203 170.00 176.60 DMH206 168.60 175.41 SiltPrison105 185.00 191.25 Autodesk Storm and Sanitary AnalysisAutodesk Storm and Sanitary AnalysisAutodesk Storm and Sanitary Analysis 16 APPENDIX E Long-Term Pollution Prevention and Stormwater Operation and Maintenance Plan November 1, 2023 Long-Term Pollution Prevention Plan and Stormwater Operation and Maintenance Plan Smith College Lazarus-Wurtele Center College Lane Northampton, MA, 01603 Prepared for: TenBerke Architects D.P.C. 41 Madison Avenue, 17th Floor. New York, NY, 10001 Prepared by: Nitsch Engineering 2 Center Plaza, Suite 430 Boston, MA 02108 Nitsch Project #15150 Northampton, MA – Long-Term Pollution Prevention Plan and Stormwater Operation and Maintenance Plan 11/01/2023, 2023 | Nitsch #15150 i TABLE OF CONTENTS SECTION 1 INTRODUCTION ..................................................................................................................... 1 SECTION 2 LONG-TERM POLLUTION PREVENTION PLAN ................................................................... 2 Storage of Hazardous Materials ......................................................................................................................................... 2 Storage of Waste Products ................................................................................................................................................. 2 Spill Prevention and Response .......................................................................................................................................... 2 Minimize Soil Erosion ......................................................................................................................................................... 2 Vehicle Washing ................................................................................................................................................................. 2 Maintenance of Lawns, Gardens, and other Landscaped Areas ....................................................................................... 3 Management of Deicing Chemicals and Snow ................................................................................................................... 3 Coordination with other Permits and Requirements ........................................................................................................... 3 SECTION 3 STORMWATER MANAGEMENT SYSTEM OPERATION AND MAINTENANCE PLAN......... 4 Introduction ......................................................................................................................................................................... 4 Stormwater Operation and Maintenance Requirements .................................................................................................... 4 Street Sweeping ................................................................................................................................................................. 6 Organic Waste and Leaf Litter Collection ........................................................................................................................... 6 Repair of the Stormwater Management System ................................................................................................................ 7 Estimated Operations and Maintenance Budget ................................................................................................................ 7 Reporting ............................................................................................................................................................................ 7 STORMWATER MANAGEMENT SYSTEM INSPECTION FORM ................................................................ 8 FIGURES 9 Figure 1: Stormwater Management System Location Map ................................................................................................ 9 Figure 2: Snow Storage Map .............................................................................................................................................. 9 Northampton, MA – Long-Term Pollution Prevention Plan and Stormwater Operation and Maintenance Plan 11/01/2023 | Nitsch #15150 1 SECTION 1 Introduction The purpose of this document is to specify the pollution prevention measures and stormwater management system operation and maintenance for the Smith College Lazurus-Wurtele Center site. The Responsible Party indicated below shall implement the management practices outlined in this document and proactively conduct operations at the project site in an environmentally responsible manner. Compliance with this Manual does not in any way dismiss the responsible party, owner, property manager, or occupants from compliance with other applicable federal, state or local laws. Responsible Party: Trustees of the Smith College Charlie Conant, Senior Project Manager 126 West Street Northampton, MA 01063 413-585-2424 This Document has been prepared in compliance with Standards 4 and 9 of the 2008 Massachusetts Department of Environmental Protection (MassDEP) Stormwater Management Standards, which state: Standard 4 The Long-Term Pollution Prevention Plan shall include the proper procedures for the following: 1. Good housekeeping; 2. Storing materials and waste products inside or under cover; 3. Vehicle washing; 4. Routine inspections of stormwater best management practices; 5. Spill prevention and response; 6. Maintenance of lawns, gardens, and other landscaped areas; 7. Storage and use of fertilizers, herbicides, and pesticides; 8. Pet waste management; 9. Operation and management of septic systems; and 10. Proper management of deicing chemicals and snow. Standard 9 The Long-Term Operation and Maintenance Plan shall at a minimum include: 1. Stormwater management system(s) owner(s); 2. The party or parties responsible for operation and maintenance, including how future property owners shall be notified of the presence of the stormwater management system and the requirement for operation and maintenance; 3. The routine and non-routine maintenance tasks to be undertaken after construction is complete and a schedule for implementing those tasks; 4. A plan that is drawn to scale and shows the location of all stormwater BMPs in each treatment train along with the discharge point; 5. A description and delineation of public safety features; and 6. An estimated operations and maintenance budget. 2 SECTION 2 Long-Term Pollution Prevention Plan The Responsible Party shall implement the following good housekeeping procedures at the project site to reduce the possibility of accidental releases and to reduce safety hazards. Storage of Hazardous Materials To prevent leaks and spills, keep hazardous materials and waste products under cover or inside. Use drip pans or spill containment systems to prevent chemicals from entering the drainage system. Inspect storage areas for materials and waste products at least once per year to determine amount and type of the material on site, and if the material requires disposal. Securely store liquid petroleum products and other liquid chemicals in federally- and state-approved containers. Restrict access to maintenance personnel and administrators. Storage of Waste Products Collect and store all waste materials in securely lidded dumpster(s) or other secure containers as applicable to the material. Keep dumpster lids closed and the areas around them clean. Do not fill the dumpsters with liquid waste or hose them out. Sweep areas around the dumpster regularly and put the debris in the garbage, instead of sweeping or hosing it into the parking lot. Legally dispose of collected waste on a regular basis. Segregate liquid wastes from solid waste and recycle through hazardous waste disposal companies, whenever possible. Contact a hazardous waste hauler for proper disposal to a hazardous waste collection center. Spill Prevention and Response Implement spill response procedures for releases of significant materials such as fuels, oils, or chemical materials onto the ground or other area that could reasonably be expected to discharge to surface or groundwater. 1. For minor spills, keep fifty (50) gallon spill control kits and Speedy Dry at all shop and work areas. 2. Immediately contact applicable Federal, State, and local agencies for reportable quantities as required by law. 3. Immediately perform applicable containment and cleanup procedures following a spill release. 4. Promptly remove and dispose of all material collected during the response in accordance with Federal, State, and local requirements. A licensed emergency response contractor may be required to assist in cleanup of releases depending on the amount of the release, and the ability of the Contractor to perform the required response. 5. Reportable quantities of chemicals, fuels, or oils are established under the Clean Water Act and enforced through MassDEP. Minimize Soil Erosion Soil erosion facilitates mechanical transport of nutrients, pathogens, and organic matter to surface water bodies. Repair all areas where erosion is occurring throughout the project site. Stabilize bare soil with riprap, seed, mulch, or vegetation. Vehicle Washing Vehicle washing will not occur within the covered service area. Northampton, MA – Long-Term Pollution Prevention Plan and Stormwater Operation and Maintenance Plan 11/01/2023 | Nitsch #15150 3 Maintenance of Lawns, Gardens, and other Landscaped Areas Pesticides and fertilizers shall not be used in the landscaped areas associated with the project site and shall not be stored on-site. Dumping of lawn wastes, brush or leaves or other materials or debris is not permitted in any Resource Area. Grass clippings, pruned branches and any other landscaped waste should be disposed of or composted in an appropriate location. Site irrigation shall be used in the landscaped areas for this project. Management of Deicing Chemicals and Snow The qualified contractor selected for snow plowing and deicing shall be made fully aware of the requirements of this section. No road salt (sodium chloride) shall be stored on-site. The use of magnesium chloride de-icing product with a 0.5 to 1.0 percent sodium chloride mix for snow and ice treatment is permitted. The product shall be stored in a locked room inside the building and shall be used at exterior stairs and walkways. The snow plow contractor shall adhere to these magnesium chloride use and storage requirements. During typical snow plowing operations, snow shall be pushed to the designated snow removal areas noted on the Snow Storage Plan (Figure 2). Snow shall not be stockpiled in wetland resource areas or the 200-foot Riverfront Area, catch basins, or bioretention basins. In severe conditions where snow cannot be stockpiled on site, the snow shall be removed from the site and properly disposed of in accordance with DEP Guideline BRP601-01. Use of sand is permitted only for impervious roadways and parking areas. If sand is applied, the snow plowed from impervious areas shall not be stored on porous asphalt. Porous asphalt areas are proposed throughout the site, as indicated on the Stormwater Management System Location Map (Figure 1). These areas will be delineated on-site using pavement markings. Porous asphalt performs well in cold climates and can reduce meltwater runoff during the snowmelt period; however there are specific winter management techniques that must be followed for porous asphalt systems. The porous asphalt areas shall be maintained during snow events as provided below: 1. Apply anti-icing treatments only when absolutely necessary (in extreme events). It is not anticipated that deicing chemicals will be required for typical winter events. 2. Plow as needed after storm events. Avoid scarifying the porous asphalt surface. Special plow blades should be used whenever possible. Raised blade is not recommended. 3. Apply the minimum amount of deicing agents during and after storms required to control compact snow and ice that are not removed by plowing. 4. Do not apply sand in porous asphalt areas “No Sanding” signs shall be posted before the first snowfall and maintenance and snow removal contractors shall be made aware of this requirement. Before winter begins, the property owner and the contractor shall review snow plowing, deicing, and stockpiling procedures. Areas designated for stockpiling should be cleaned of any debris. Street and parking lot sweeping should be followed in accordance with the Operation and Maintenance Plan. Coordination with other Permits and Requirements Certain conditions of other approvals affecting the long-term management of the property shall be considered part of this Long-Term Pollution Prevention Plan. The Owner shall become familiar with those documents and comply with the guidelines set forth in those documents. 4 SECTION 3 Stormwater Management System Operation and Maintenance Plan Introduction This Operation and Maintenance Plan (O&M Plan) for Smith College Lazarus-Wurtele Center site is required under Standard 9 of the 2008 MassDEP Stormwater Handbook to provide best management practices for implementing maintenance activities for the stormwater management system in a manner that minimizes impacts to wetland resource areas. The Owner shall implement this O&M Plan and proactively conduct operations at the site in an environmentally responsible manner. Compliance with this O&M Plan does not in any way dismiss the Owner from compliance with other applicable Federal, State or local laws. Routine maintenance during construction and post-development phases of the project, as defined in the Operation and Maintenance Plan, shall be permitted without amendment to the Order of Conditions. A continuing condition in the Certificate of Compliance shall ensure that maintenance can be performed without triggering further filings under the Wetlands Protection Act. All stormwater best management practices (BMPs) shall be operated and maintained in accordance with the design plans and the Operation and Maintenance Plan approved by the issuing authority. The Owner shall: 1. Maintain an operation and maintenance log for the last three years, including inspections, repairs, replacement, and disposal (for disposal the log shall indicate the type of material and the disposal location). This is a rolling log in which the responsible party records all operation and maintenance activities for the past three years. 2. Make this log available to MassDEP and the Conservation Commission upon request; and 3. Allow members and agents of the MassDEP and the Conservation Commission to enter and inspect the premises to evaluate and ensure that the Owner complies with the Operation and Maintenance requirements for each BMP. Stormwater Operation and Maintenance Requirements Inspect and maintain the stormwater management system as directed below. Refer to the Stormwater Management System Location Map (Figure 1) for the location of each component of the system. Repairs to any component of the system shall be made as soon as possible to prevent any potential pollutants (including silt) from entering the resource areas. Deep Sump and Hooded Catch Basins and Silt Prisons Inspect or clean catch basins four times per year and at the end of foliage and snow-removal seasons. Other inspection and maintenance requirements include: 1. Remove organic material, sediment and hydrocarbons four times per year or whenever the depth of deposits is greater than or equal to one half the depth from the bottom of the invert of the lowest pipe in the basin. 2. Always clean out catch basins after street sweeping. If any evidence of hydrocarbons is found during inspection, immediately remove the material using absorbent pads or other suitable measures and dispose of legally. Remove other accumulated debris as necessary. 3. If handling runoff from land uses with higher potential pollutant loads or discharging runoff near or to a critical area, more frequent cleaning may be necessary. 4. Transport and disposal of accumulated sediment off-site shall be in accordance with applicable local, state and federal guidelines and regulations. Northampton, MA – Long-Term Pollution Prevention Plan and Stormwater Operation and Maintenance Plan 11/01/2023 | Nitsch #15150 5 5. Perform any additional maintenance per Silt Prison manufacturer guidelines and recommendations. Permeable Pavers Permeable paver areas are proposed throughout the site, as indicated on the Civil Utility Plan. Frequent cleaning and maintenance of the permeable paver surface is critical to prevent clogging. Frequent vacuum sweeping along with replenishing joint material or reseeding grass pavers is required. No winter sanding shall be conducted on the permeable surface. For proper maintenance: 1. Post signs identifying permeable paver areas. 2. Minimize salt use during winter months. 3. No winter sanding is allowed. 4. Keep landscaped areas well maintained to prevent soil from being transported onto the pavers. 5. Regularly monitor the permeable paver surface to make sure that it drains properly after storm events. Inspect surface annually for deterioration or spalling. 6. At a minimum, the permeable pavers shall be cleaned after the winter season and every three months thereafter. This requirement may be adjusted as needed, based on regular visual inspections of the permeable paver surface. 7. For paving stones, add joint material to replace material that has been transported. Reseed grass pavers to fill in bare spots. 8. Never reseal or repave with impermeable materials. 9. Once per year, the infiltrative capacity of the porous pavement should be tested by running a hose over each paver area for 30 minutes. 10. When infiltrative capacity of pavers is reduced to less than the design rate, the pavers shall be replaced down to the choker course. 11. Attach rollers to the bottoms of snowplows to prevent them from catching on the edges of grass pavers and some paving stones. Area Drains Inspect area drains at least once per month and remove debris from the grate. Clean out accumulated sediments at least once per year and more frequently as necessary. Green Roofs Perform routine maintenance on all components of the green roofs as directed by the system manufacturer. This includes monitoring the planting system and maintaining healthy vegetation. Landscape Filter Inspect access basins in the landscape filter at least once per year and more frequently as necessary. Vegetated Swales Vegetated swales shall be inspected twice per year during the first year after construction. In subsequent years, the swales shall be inspected annually and after rain events greater than 3 inches in 24 hours. Inspection and maintenance procedures for drainage channels are provided below: 1. Inspect the riprap on the channel bottom and side slopes for signs of erosion and formation of rills and gullies. Replace riprap as necessary. 2. Inspect channels the first few months after construction and twice per year thereafter to make sure 6 vegetation is adequate and for signs of rilling and gullying. Repair any rills or gullies. Replace dead vegetation. 3. Remove accumulated trash and debris annually. 4. Remove sediment as needed at least once per year. Use hand methods (i.e. a person with a shovel) when cleaning to minimize disturbance to vegetation and underlying soils. 5. Mow as necessary. Grass height shall be between 3 and 6 inches. 6. Reseed as necessary. 7. Check Dams: Inspect check dams after every significant rainfall event. Repair damage as needed. Remove sediment as needed. Bioretention Areas Perform annual maintenance of all components of the bioretention area, including plants, soil, and mulch. Table 1, below, outlines recommended maintenance activities. Table 1. Bioretention area maintenance recommendations Location Description Frequency Time of Year Surface Inspect and remove trash Monthly Year round Soil Inspect and repair erosion Monthly Year round Organic Layer Replenish void areas Annually Spring Plants Water vegetation at end of day for 14 consecutive days after planting Immediately after planting As needed Fertilize Annually Spring Mow grass 2 to 12 times per year As needed Remove and replace all dead and diseased vegetation that cannot be treated Annually Spring Treat all diseased trees and shrubs As needed Variable During and after storm events, record the length of time standing water remains in the bioretention areas. If the time is greater than 72 hours, thoroughly inspect the basins for signs of clogging and develop a corrective action plan. The corrective action plan, prepared by a qualified professional, will outline procedures to restore infiltrative function. The owner of the site shall take immediate action to implement these corrective measures. Inspect pretreatment devices and bioretention cells regularly for sediment build-up, structural damage, and standing water. Never store snow in bioretention areas. Street Sweeping Nitsch Engineering does not take credit for street sweeping of the site for annual load reduction of Phosphorus and TSS calculations as part of the Project. Organic Waste and Leaf Litter Collection Nitsch Engineering does not take credit for collection of organic waste and leaf litter for annual load reduction of Phosphorus and TSS calculations as part of the Project. Northampton, MA – Long-Term Pollution Prevention Plan and Stormwater Operation and Maintenance Plan 11/01/2023 | Nitsch #15150 7 Repair of the Stormwater Management System The stormwater management system shall be maintained. The repair of any component of the system shall be made as soon as possible to prevent any potential pollutants including silt from entering the resource areas or the existing closed drainage system. Estimated Operations and Maintenance Budget An Operations and Maintenance Budget was prepared in compliance with the MassDEP Stormwater Standards. Table 2. Operations and Maintenance Budget BMP Type # of BMPs Annual O & M Cost (per BMP) Total Cost Catch Basin with Silt Prisons 5 $240-$480 $1,200-$2,400 Area Drain 6 $60-$120 $360-$720 Bioretention Basin 11 $240-$480 $2,640-$5,280 Permeable Pavers 3 $200-$400 $600-$1,200 Total: $4,800-$9,600 Reporting The Owner shall maintain a record of drainage system inspections and maintenance (per this Plan) and submit a yearly report to the Northampton Conservation Commission. 8 STORMWATER MANAGEMENT SYSTEM INSPECTION FORM SMITH COLLEGE Inspected by:____________ Northampton, MA Date:_________________ Component Status/Inspection Action Taken Deep Sump Catch Basins, Area Drains and Drain Manholes, Silt Prisons Bioretention Basins Landscape Filter Green Roof Permeable Pavers General site conditions – evidence of erosion, etc. SUBMIT COPIES OF STORMWATER MANAGEMENT SYSTEM INSPECTION FORM TO THE NORTHAMPTON CONSERVATION COMMISSION WITH THE YEARLY REPORT. Northampton, MA – Long-Term Pollution Prevention Plan and Stormwater Operation and Maintenance Plan 11/01/2023 | Nitsch #15150 9 FIGURES Figure 1: Stormwater Management System Location Map Figure 2: Snow Storage Map THIS SIDE OF LINE:NHESP PRIORITY HABITATOF RARE SPECIES &NHESP ESTIMATED HABITATOF RARE WILDLIFETHIS SIDE OF LINE: NHESP PRIORITY HABITAT OF RARE SPECIES & NHESP ESTIMATED HABITAT OF RARE WILDLIFE PARK ANNEX HOPKINS HOUSE WESLEY HOUSE HAVEN HOUSE CAMPUS CENTER CHAPIN HOUSE LYMAN CONSERVATORY 8 COLLEGE LANE ADMISSION'S OFFICE CHAPIN LAWNCOLLEGE LANETenBerke Architects D.P.C. 41 Madison Avenue, 17th Floor New York NY 10001 212 229 9211 TenBerke.com 2023 TenBerke Architects D.P.C.C Architect: ALL WORK SHALL BE CARRIED OUT IN ACCORDANCE WITH ALL CODES AND REGULATIONS HAVING JURISDICTION OVER THIS SITE LOCATION. ALL DIMENSIONS AND INFORMATION SHALL BE CHECKED AND VERIFIED ON THE JOB AND ANY DISCREPANCIES MUST BE REPORTED TO THE ARCHITECT. THESE DRAWINGS MUST NOT BE SCALED. THE DESIGN AND CONTRACT DOCUMENTS ARE THE COPYRIGHT PROPERTY OF THE ARCHITECT AND MAY NOT BE REPRODUCED, ALTERED, OR REUSED WITHOUT THE ARCHITECT'S WRITTEN APPROVAL. Project: Drawing Status: Date: Drawing History: Scale: SEAL FOR PERMIT ONLY C 6 5 4 3 2 1 A B D E CODE CONSULTANT 617.523.8227 rwsullivan.com 529 Main Street, Suite 203 Boston, MA 02129 RW SULLIVAN GRAPHICS 1.347.529.4562 afreeman.co 63 Flushing Ave., Unit 243 Brooklyn, NY 11205 A FREEMAN HARDWARE 201.398.6583 somspec.net 462 Sheffield Road Ridgewood, NJ 07450 SOMSPEC ACOUSTICS / AV / IT / SECURITY 212.725.6800 www.smwllc.com 275 Madison Ave New York, NY 10016 SHEN MILSON WILKE LIGHTING 212.201.5790 www.oneluxstudio.com 158 West 29th Street, 10th Floor New York, NY 10001 ONE LUX STUDIO MEP-FP ENGINEER 203.663.5614 altieriseborwieber.com/ 171 Milk St 3rd Floor, Boston MA 02109 ALTIERI SEBOR WIEBER LLC STRUCTURAL ENGINEER / SUSTAINABILITY / FACADE 1.917.661.7800 www.thorntontomasetti.com 120 Broadway 15th Floor New York, NY 10271-0016 THORNTON TOMASETTI LANDSCAPE ARCHITECTURE 212.431.3609 www.mnlandscape.com 120 Broadway, #1040 New York, NY 10271 MNLA CIVIL ENGINEER 617.338.0063 www.nitscheng.com 2 Center Plaza, Suite 430, Boston, MA 02108 NITSCH ENGINEERING As indicated SMITH COLLEGE LAZARUS-WURTELE CENTER COLLEGE LN NORTHAMPTON, MA, 01063 DBP Project No. 4213 ISSUED FOR SITE PERMIT 11/01/2023 NO.DESCRIPTION DATE SITE PERMIT SUBMISSION 11/01/2023 C-400 SITE UTILITY PLAN STORMWATER MANAGEMENT SYSTEM LOCATION MAP FIG 1 BIORETENTION BASIN (TYP.) PERMEABLE PAVERS (TYP.) LANDSCAPE FILTER BIORETENTION BASIN (TYP.) SILT PRISON CATCH BASIN SILT PRISON CATCH BASIN SILT PRISON CATCH BASIN GRASSED SWALE GRASSED SWALE GREEN ROOF THIS SIDE OF LINE:NHESP PRIORITY HABITATOF RARE SPECIES &NHESP ESTIMATED HABITATOF RARE WILDLIFETHIS SIDE OF LINE: NHESP PRIORITY HABITAT OF RARE SPECIES & NHESP ESTIMATED HABITAT OF RARE WILDLIFE PARK ANNEX HOPKINS HOUSE WESLEY HOUSE HAVEN HOUSE CAMPUS CENTER CHAPIN HOUSE LYMAN CONSERVATORY 8 COLLEGE LANE ADMISSION'S OFFICE CHAPIN LAWNCOLLEGE LANECOLLEGE LANECHAPIN WAYCOLLEGE LANEC H A P I N W A Y TenBerke Architects D.P.C. 41 Madison Avenue, 17th Floor New York NY 10001 212 229 9211 TenBerke.com 2023 TenBerke Architects D.P.C.C Architect: ALL WORK SHALL BE CARRIED OUT IN ACCORDANCE WITH ALL CODES AND REGULATIONS HAVING JURISDICTION OVER THIS SITE LOCATION. ALL DIMENSIONS AND INFORMATION SHALL BE CHECKED AND VERIFIED ON THE JOB AND ANY DISCREPANCIES MUST BE REPORTED TO THE ARCHITECT. THESE DRAWINGS MUST NOT BE SCALED. THE DESIGN AND CONTRACT DOCUMENTS ARE THE COPYRIGHT PROPERTY OF THE ARCHITECT AND MAY NOT BE REPRODUCED, ALTERED, OR REUSED WITHOUT THE ARCHITECT'S WRITTEN APPROVAL. Project: Drawing Status: Date: Drawing History: Scale: SEAL FOR PERMIT ONLY C 6 5 4 3 2 1 A B D E CODE CONSULTANT 617.523.8227 rwsullivan.com 529 Main Street, Suite 203 Boston, MA 02129 RW SULLIVAN GRAPHICS 1.347.529.4562 afreeman.co 63 Flushing Ave., Unit 243 Brooklyn, NY 11205 A FREEMAN HARDWARE 201.398.6583 somspec.net 462 Sheffield Road Ridgewood, NJ 07450 SOMSPEC ACOUSTICS / AV / IT / SECURITY 212.725.6800 www.smwllc.com 275 Madison Ave New York, NY 10016 SHEN MILSON WILKE LIGHTING 212.201.5790 www.oneluxstudio.com 158 West 29th Street, 10th Floor New York, NY 10001 ONE LUX STUDIO MEP-FP ENGINEER 203.663.5614 altieriseborwieber.com/ 171 Milk St 3rd Floor, Boston MA 02109 ALTIERI SEBOR WIEBER LLC STRUCTURAL ENGINEER / SUSTAINABILITY / FACADE 1.917.661.7800 www.thorntontomasetti.com 120 Broadway 15th Floor New York, NY 10271-0016 THORNTON TOMASETTI LANDSCAPE ARCHITECTURE 212.431.3609 www.mnlandscape.com 120 Broadway, #1040 New York, NY 10271 MNLA CIVIL ENGINEER 617.338.0063 www.nitscheng.com 2 Center Plaza, Suite 430, Boston, MA 02108 NITSCH ENGINEERING As indicated SMITH COLLEGE LAZARUS-WURTELE CENTER COLLEGE LN NORTHAMPTON, MA, 01063 DBP Project No. 4213 ISSUED FOR SITE PERMIT 11/01/2023 NO.DESCRIPTION DATE SITE PERMIT SUBMISSION 11/01/2023 SS-100 SNOW STORAGE PLAN SNOW STORAGE MAP FIG 2 Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 17 APPENDIX F Draft Stormwater Pollution Prevention Plan (SWPPP) i DRAFT Stormwater Pollution Prevention Plan (SWPPP) For Construction Activities At: Smith College Lazarus-Wurtele Center College Lane Northampton, MA, 01063 Site Telephone Number: 413-584-2700 SWPPP Prepared For: TenBerke Architects D.P.C. Arthi Krishnamoorthy, Senior Principal 41 Madison Avenue, 17th Floor. New York, NY, 10001 T: 212-229-9211 TenBerke.com SWPPP Prepared By: Nitsch Engineering Coleman Horsley, PE Moses Matovu 2 Center Plaza Boston, MA 02108 T: 617-338-0063 F: 617-338-6472 SWPPP Preparation Date: 11/01/2023 Estimated Project Dates: Project Start Date: XX/XX/XXXX Project Completion Date: XX/XX/XXXX DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center ii Contents SECTION 1: CONTACT INFORMATION/RESPONSIBLE PARTIES ........................................ 0 1.1 Operator(s) / Subcontractor(s) ...................................................................................... 0 1.2 Stormwater Team ........................................................................................................... 2 SECTION 2: SITE EVALUATION, ASSESSMENT, AND PLANNING ....................................... 3 2.1 Project/Site Information ................................................................................................. 3 2.2 Discharge Information ................................................................................................... 4 2.3 Nature of the Construction Activities ........................................................................... 6 2.4 Sequence and Estimated Dates of Construction Activities ........................................ 7 2.5 Authorized Non-Stormwater Discharges...................................................................... 8 2.6 Site Maps ........................................................................................................................ 9 SECTION 3: DOCUMENTATION OF COMPLIANCE WITH OTHER FEDERAL REQUIREMENTS .....................................................................................................................10 3.1 Endangered Species Protection ..................................................................................10 3.2 Historic Properties Screening Process .......................................................................12 3.3 Safe Drinking Water Act Underground Injection Control Requirements ..................13 SECTION 4: EROSION AND SEDIMENT CONTROLS REQUIREMENTS ..............................13 4.1 Natural Buffers or Equivalent Sediment Controls ......................................................13 4.2 Perimeter Controls ........................................................................................................13 4.3 Sediment Track-Out ......................................................................................................15 4.4 Stockpiled Sediment or Soil .........................................................................................16 4.5 Minimize Dust ................................................................................................................17 4.6 Minimize the Disturbance of Steep Slopes .................................................................18 4.7 Preserve Native Topsoil ...............................................................................................19 4.8 Minimize Soil Compaction ............................................................................................19 DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center iii 4.9 Storm Drain Inlets .........................................................................................................20 4.10 Minimize Erosion of Stormwater Conveyances ..........................................................21 4.11 Sediment Basins ...........................................................................................................21 4.12 Chemical Treatment ......................................................................................................21 4.13 Dewatering Practices ....................................................................................................21 4.14 Other Stormwater Controls ..........................................................................................21 4.15 Site Stabilization ...........................................................................................................21 SECTION 5: POLLUTION PREVENTION STANDARDS .........................................................22 5.1 Potential Sources of Pollution .....................................................................................22 5.2 Spill Prevention and Response ....................................................................................24 5.3 Fueling and Maintenance of Equipment or Vehicles ..................................................24 5.4 Washing of Equipment and Vehicles ...........................................................................25 5.5 Storage, Handling, and Disposal of Construction Products, Materials, and Wastes 25 5.6 Washing of Applicators and Containers used for Paint, Concrete, or Other Materials 28 5.7 Fertilizers .......................................................................................................................29 5.8 Other Pollution Prevention Practices ..........................................................................29 SECTION 6: INSPECTION, MAINTENANCE, AND CORRECTIVE ACTION ...........................30 6.1 Inspection Personnel and Procedures ........................................................................30 6.2 Corrective Action ..........................................................................................................31 6.3 Delegation of Authority ................................................................................................31 SECTION 7: SWPPP TRAINING LOG .....................................................................................32 SECTION 8: CERTIFICATION AND NOTIFICATION ...............................................................33 SECTION 9: TURBIDITY BENCHMARK MONITORING FOR DEWATERING DISCHARGES 34 SWPPP ATTACHMENTS .........................................................................................................36 DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 0 SECTION 1: CONTACT INFORMATION/RESPONSIBLE PARTIES 1.1 Operator(s) / Subcontractor(s) Operator(s): Construction Manager Responsibilities: Construction Manager shall maintain the Stormwater Pollution Prevention Plan (SWPPP) documentation and will conduct and document self-inspections required under the 2022 Construction General Permit (CGP) once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. Construction Manager will provide copies of inspections reports to the Owner’s Representative within 24 hours following each inspection. Incidents of non-compliance will be immediately brought to the attention of the Owner’s Representative. Construction Manager shall be responsible for maintaining compliance with the SWPPP, including all requirements in the CGP and will maintain erosion and sediment control Best Management Practices (BMPs) in all areas of the site under its day-to-day control. Construction Manager shall file a Notice of Intent (NOI) to be covered by the CGP and obtain coverage by the Environmental Protection Agency (EPA) before beginning construction at the project. Permit coverage will be maintained throughout the project. Construction Manager shall not file a Notice of Termination (NOT) until all disturbed areas of the site under its day-to-day control have been fully stabilized with permanent erosion controls that satisfy the final stabilization requirements in the CGP or have met another criteria of the NOT. Photo documentation shall be included with the NOT. Construction Manager will maintain a clean site and construction trash and debris will be picked up and disposed of properly by the end of each day. Each Operator is responsible for advising employees and subcontractors working on this project of the requirements in the CGP and SWPPP. Particular emphasis should be placed on ensuring that employees and subcontractors do not damage BMPs and maintain compliance with the CGP. Construction Manager Company Name Construction Manager Contact Person, Position Street Address Town, State, Zip Code T: xxx-xxx-xxxx Email address: DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 1 Owner’s Representative Responsibilities: TenBerke Architects D.P.C. shall provide general oversight of the project including review of the SWPPP and any amendments, inspection reports, and corrective actions. TenBerke Architects D.P.C. shall file a NOI to be covered by the CGP and obtain coverage by the EPA before beginning construction at the project. Permit coverage will be maintained throughout the project. TenBerke Architects D.P.C. shall not file a notice of Termination until all disturbed areas of the site have been fully stabilized with permanent erosion controls that satisfy the final stabilization requirements in the CGP. Photo documentation shall be included with the NOT. TenBerke Architects D.P.C. will coordinate with the Construction Manager to maintain a clean site so that trash and debris will be picked up and disposed of properly by the end of the day. Each Operator is responsible for advising employees and subcontractors working on this project of the requirements in the CGP and SWPPP. Particular emphasis should be placed on ensuring that employees and subcontractors do not damage BMPs and maintain compliance with the CGP. TenBerke Architects D.P.C. Arthi Krishnamoorthy, Senior Principal 220 Fifth Avenue, 7th Floor. New York, NY, 10001 T: 212-229-9211 Email Address: info@tenberke.com Site Contractor: Company Name Contact person, Position Street Address Town, State, Zip Code T: xxx-xxx-xxxx Email Address: Emergency 24-Hour Contact: Company Emergency Contact person, Position T: xxx-xxx-xxxx DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 2 1.2 Stormwater Team Construction Manager: Company Stormwater Role/Responsibility: Responsible for overseeing the development of the SWPPP, modifications and updates to the SWPPP, and for compliance with the requirements in the CGP (e.g., installing and maintaining stormwater controls, conducting site inspections, picking up trash, application and storage of treatment chemicals (if applicable), taking corrective actions where required, etc.). Responsible for having ready access to an electronic or paper copy of the 2022 CGP and the SWPPP. Contact: Construction Manager Contact Person, Position T: xxx-xxx-xxxx Email address I, Construction Manager Contact Person, have read the CGP and Understand the Applicable Requirements and have completed Training Required by CGP Part 6.2. ☐ Yes Date: __________ Site Contractor: Company Stormwater Role/Responsibility: Responsible for compliance with the requirements in this permit (e.g., installing and maintaining stormwater controls, conducting site inspections, repairing controls and taking corrective actions where required, etc.). Responsible for having ready access to an electronic or paper copy of the 2022 CGP and the SWPPP. Contact: Contact Person, Position T: xxx-xxx-xxxx Email Address I, Site Contractor Contact Person, have read the CGP and Understand the Applicable Requirements and have completed Training Required by CGP Part 6.2. ☒ Yes Date: __________ Refer to the Subcontractor Certifications/Agreements in Attachment G. Refer to SWPPP Training Documentation in Attachment I. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 3 SECTION 2: SITE EVALUATION, ASSESSMENT, AND PLANNING 2.1 Project/Site Information Project Name and Address Project/Site Name: Smith College Lazarus-Wurtele Center Project Street/Location: College Lane City/Town: Northampton State: Massachusetts ZIP Code: 01063 County or Similar Subdivision: Hampshire County Project Latitude/Longitude (Use one of three possible formats, and specify method) Latitude: Longitude: 1. 42º 18' 58.68'' N (degrees, minutes, seconds) 1. 72º 38' 25.11'' W (degrees, minutes, seconds) Method for determining latitude/longitude: USGS topographic map (specify scale: ) GPS Other (please specify): Google Earth Pro Horizontal Reference Datum: NAD 27 NAD 83 WGS 84 If you used a U.S.G.S topographic map, what was the scale? ____________________________ Additional Project Information Is the project/site located on Indian country lands, or located on a property of religious or cultural significance to an Indian tribe? Yes No Are you applying for permit coverage as a “federal operator” as defined in Appendix A of the CGP? Yes No Will there be demolition of any structure built or renovated before January 1, 1980? Yes No If yes, do any of the structures being demolished have at least 10,000 square feet of floor space? Yes No Was pre-development land use used for agriculture (see Appendix A of the CGP for definition of “agricultural land”)? Yes No Type of Construction Site (check all that apply): Single-Family Residential Multi-Family Residential Commercial Industrial Institutional Highway or Road Utility Other _____________ DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 4 2.2 Discharge Information Does your project/site discharge stormwater into a Municipal Separate Storm Sewer System (MS4)? Yes No Are there any surface waters that are located within 50 feet of your construction disturbances? Yes No DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 5Table 1 – Names of Receiving Waters Name(s) of the first surface water that receives stormwater directly from your site and/or from the MS4 (note: multiple rows provided where your site has more than one point of discharge that flows to different surface waters) 001. Paradise Pond (part of the Mill River) Table 2 – Impaired Waters / TMDLs (Answer the following for each surface water listed in Table 1 above) Is this surface water listed as “impaired” on the CWA303(d) list? If you answered yes, then answer the following: What pollutant(s) are causing the impairment? Has a TMDL been completed? Title and ID of the TMDL document Pollutant(s) for which there is a TMDL 001. YES NO Escherichia Coli (E. coli) YES NO Table 3 – Tier 2, 2.5, or 3 Waters (Answer the following for each surface water listed in Table 1 above) Is this surface water designated as a Tier 2, Tier 2.5, or Tier 3 water? If you answered yes, specify which Tier (2, 2.5, or 3) the surface water is designated as? 001. YES NO DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 6 2.3 Nature of the Construction Activities General Description of Project The project is a redevelopment of the existing site and includes demolition of the existing building to construct a new building, construction of new accessible and pedestrian walkways and utilities to support the proposed building in addition to construction of a new stormwater management system. Size of Construction Project Size of Property: 1.26 acres Total Area of Construction Disturbances: 0.94 acres Maximum Area to be Disturbed at Any One Time: 0.94 acres Type of Construction Site (check all that apply): Single-Family Residential Multi-Family Residential Commercial Industrial Institutional Highway or Road Utility Other Will you be discharging dewatering water from your site? ☐ Yes ☒ No If yes, will you be discharging dewatering water from a current or former Federal or State remediation site? ☐ Yes ☒ No Construction Support Activities Include a description of the construction support activities or reference Site Maps in Attachment A that include this information. Contact Information for Construction Support Activity: Name: XXX Telephone: XXX-XXX-XXXX Email: XXXX Address and/or Latitude and Longitude: Business Hours Day-Day Xa.m-Xp.m. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 7 2.4 Sequence and Estimated Dates of Construction Activities Phase I: Demolition This phase consists of the demolition of site features and utilities as shown on the Site Preparation Plan provided in Attachment A. · Schedule: XXX-XXX · Area Disturbed During Phase: 0.94 acres. · This phase will include the installation of all stormwater control measures as shown on the Site Preparation Plan provided in Attachment A. Stormwater controls will be removed at the end of Phase III upon stabilization of the site. Phase II: Exterior Utilities This phase consists of the installation of all exterior utilities on the site. · Schedule: XXX-XXX · Area Disturbed During Phase: 0.94 acres. · All stormwater controls will be installed prior to earth disturbance as described in Phase I. Stormwater controls will be removed at the end of Phase III upon stabilization of the site. Phase III: Landscaping and Paving This phase consists of the landscaping and paving of the site. · Schedule: XXX-XXX · Area Disturbed During Phase: 0.94 acres · Stormwater controls will be installed as described in Phase I. Stormwater controls will remain in place until site work is complete and the site is stabilized. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 8 2.5 Authorized Non-Stormwater Discharges List of Allowable Non-Stormwater Discharges Present at the Site Type of Allowable Non-Stormwater Discharge Likely to be Present at Your Site? Discharges from emergency fire-fighting activities YES NO Fire hydrant flushings YES NO Landscape irrigation YES NO Waters used to wash vehicles and equipment, provided that there is no discharge of soaps, solvents, or detergents used for such purposes YES NO Water used to control dust YES NO Potable water including uncontaminated water line flushings YES NO External building washdown, provided soaps, solvents, and detergents are not used, and external surfaces do not contain hazardous substances (as defined in Appendix A of the CGP) (e.g., paint or caulk containing polychlorinated biphenyls (PCBs)) YES NO Pavement wash waters, provided spills or leaks of toxic or hazardous substances have not occurred (unless all spill material has been removed) and where soaps, solvents, and detergents are not used. YES NO Uncontaminated air conditioning or compressor condensate YES NO Uncontaminated, non-turbid discharges of ground water or spring water YES NO Foundation or footing drains where flows are not contaminated with process materials such as solvents or contaminated groundwater YES NO Uncontaminated construction dewatering water discharged in accordance with Part 2.4 of the CGP YES NO Note: You are prohibited from directing pavement wash waters directly into any water of the U.S., storm drain inlet, or stormwater conveyance, unless the conveyance is connected to a sediment basin, sediment trap, or similarly effective control. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 9 2.6 Site Maps Site Maps must include the following: a) Boundaries of the property. The map(s) in the SWPPP must show the overall boundary of the property. b) Locations where construction activities will occur. The map(s) in the SWPPP must show the locations where construction activities will occur, including i. Locations where earth-disturbing activities will occur (note any phasing), including any demolition activities; ii. Approximate slopes before and after major grading activities (note any steep slopes); iii. Locations where sediment, soil, or other construction materials will be stockpiled; iv. Any water of the U.S. crossings; v. Designated points where vehicles will exit onto paved roads; vi. Locations of structures and other impervious surfaces upon completion of construction; and vii. Locations of onsite and off-site construction support activity areas covered by the permit (see Part 1.2.1.c). c) Locations of any receiving waters, including wetlands within and one mile downstream of the site’s discharge point(s). Also identify if any are listed as impaired, or are identified as a Tier 2, Tier 2.5, or Tier 3 water. d) Areas of federally-listed critical habitats for endangered or threatened species within the site and/or at discharge locations. e) Type and extent of pre-construction cover on the site (e.g., vegetative cover, forest, pasture, pavement, structures). f) Drainage patterns of stormwater and authorized non-stormwater before and after major grading activities. g) Stormwater and authorized non-stormwater discharge locations. The permit requires the site map to show information pertaining to discharge locations including: i. Locations where stormwater and/or authorized non-stormwater will be discharged to storm drain inlets, including a notation of whether the inlet conveys stormwater to a sediment basin, sediment trap, or similarly effective control; and ii. Locations where stormwater or allowable non-stormwater will be discharged directly to receiving waters, including wetlands (i.e., not via a storm drain inlet). iii. Locations where turbidity benchmark monitoring will take place to comply with Part 3.3, if applicable to your site. h) Locations of all potential pollutant-generating activities identified in Part 7.2.3.g. The permit requires identification in the site map of all potential pollutant-generating activities identified in Part 7.2.3.g. i) Designated areas where construction wastes that are covered by the exception in Part 2.3.3e.ii (i.e., they are not pollutant-generating) will be stored. j) Locations of stormwater controls, including natural buffer areas and any shared controls utilized to comply with this permit. The permit requires identification on the site map of the location of stormwater control measures. k) Locations where polymers, flocculants, or other treatment chemicals will be used and stored. The permit requires identification on the site map of the locations where polymers, flocculants, or other treatment chemicals will be used and stored. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 10 SECTION 3: DOCUMENTATION OF COMPLIANCE WITH OTHER FEDERAL REQUIREMENTS 3.1 Endangered Species Protection The following section identifies which criterion the project is eligible for coverage under the 2022 CGP using information from both the National Marine Fisheries Services (NMFS) and U.S. Fish and Wildlife Service (USFWS) to identify Endangered Species Act-listed (ESA-listed) species and designated critical habitat. Eligibility Criterion Under which criterion listed in Appendix D of the CGP are you eligible for coverage under this permit? A B C D E F Check to confirm you have provided documentation in your SWPPP as required by CGP Appendix D. For reference purposes, the eligibility criteria listed in Appendix D of the CGP are as follows: Criterion A. No ESA-listed species and/or designated critical habitat present in action area. Using the process outlined in Appendix D of the CGP, you certify that ESA-listed species and designated critical habitat(s) under the jurisdiction of the USFWS or NMFS are not likely to occur in your site’s “action area” as defined in Appendix A of the CGP. Note: NMFS’ jurisdiction includes ESA-listed marine and estuarine species that spawn in inland rivers. Criterion B. Eligibility requirements met by another operator under the 2022 CGP. The construction site’s discharges and discharge-related activities were already addressed in another operator’s valid certification of eligibility for your action area under eligibility Criterion A, C, D, E, or F of the 2022 CGP and you have confirmed that no additional ESA-listed species and/or under the jurisdiction of USFWS and/or NMFS not considered in the prior certification may be present or located in the “action area”. To certify your eligibility under this Criterion, there must be no lapse of NPDES permit coverage in the other operator’s certification. By certifying eligibility under this Criterion, you agree to comply with any conditions upon which the other upon which the other CGP operator's certification was based. You must include in your NOI the NPDES ID from the other operator’s notification of authorization under this permit and list any measures that you must comply with. If your certification is based on another 2022 CGP operator’s certification under Criterion C, you must provide EPA with the relevant supporting information required of existing dischargers in Criterion C in your NOI form. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 11 Criterion C. Discharges not likely to result in any short- or long-term adverse effects to ESA-listed species and/or designated critical habitat. ESA-listed species and/or designated critical habitat(s) under the jurisdiction of the USFWS and/or NMFS are likely to occur in or near your site’s “action area,” and you certify to EPA that your site’s discharges and discharge-related activities are not likely to result in any short- or long-term adverse effects to ESA-listed threatened or endangered species and/or designated critical habitat. This certification may include consideration of any stormwater controls and/or management practices you will adopt to ensure that your discharges and discharge- related activities are not likely to result in any short- or long-term adverse effects to ESA-listed species and/or designated critical habitat. To certify your eligibility under this criterion, indicate in your NOI: 1) the ESA-listed species and/or designated habitat located in your “action area” using the process outlined in Appendix D of this permit; 2) the distance between the site and the listed species and/or designated critical habitat in the action area (in miles); and 3) a rationale describing specifically how short- or long- term adverse effects to ESA-listed species will be avoided from the discharges and discharge-related activities. Note: You must also include a copy of your site map from your SWPPP showing the upland and in-water extent of your “action area” with your NOI.) Criterion D. Coordination with USFWS and/or NMFS has successfully concluded. Coordination between you and the USFWS and/or NMFS has concluded. The coordination must have addressed the effects of your site’s discharges and discharge-related activities on ESA-listed species and/or designated critical habitat under the jurisdiction of USFWS and/or NMFS, and resulted in a written confirmation from USFWS and/or NMFS that the effects of your site’s discharges and discharge-related activities are not likely to result in any short- or long-term adverse effects By certifying eligibility under this criterion, you agree to comply with any conditions you must meet for your site’s discharges and discharge-related activities to not likely result in any short- or long-term adverse effects. You must include copies of the correspondence between yourself and the Services in your SWPPP and your NOI. Criterion E. ESA Section 7 consultation has successfully concluded. Consultation between a Federal Agency and the USFWS and/or NMFS under section 7 of the ESA has been concluded. Consultation can be either formal or informal, and would have occurred only as a result of a separate Federal action (e.g. during application for an individual wastewater discharge permit or the issuance of a wetlands dredge and fill permit), and the consultation must have addressed the effects of the construction site activity’s discharges and discharge-related activities on all ESA-listed threatened or endangered species and all designated critical habitat under the jurisdiction of each Service, as appropriate, in your action area. The result of this consultation must be either: i. a biological opinion currently in effect that determined that the action in question (taking into account the effects of your site’s discharges and discharge-related activities) is likely to adversely affect, but is not likely to jeopardize the continued existence of listed species or result in the destruction or adverse modification of critical habitat; The biological opinion must have included the effects of your facility’s discharges and discharge-related activities on all the listed species and designated critical habitat in your action area under the jurisdiction of each Service, as appropriate. To be eligible under (i), any reasonable and prudent measures specified in the incidental take statement must be implemented; DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 12 ii. written concurrence (e.g. letter of concurrence) from the applicable Service(s) with a determination that your site’s discharges and discharge-related activities are not likely to adversely affect USFWS and/or NMFS as part of this worksheet. ESA-listed species and/or designated critical habitat. The concurrence letter must have included the effects of your facility’s discharges and discharge-related activities on all the ESA-listed species and/or designated critical habitat on your species list(s) acquired The consultation does not warrant reinitiation under 50 CFR §402.16; or, if reinitiation of consultation is required (e.g., due to a new species listing, critical habitat designation, or new information), the Federal action agency has reinitiated the consultation and the result of the consultation is consistent with the statements above. (Note: you must include any reinitiation documentation from the Services or consulting Federal agency with your NOI.) You must include copies of the correspondence between yourself and the Services in your SWPPP and your NOI. Criterion F. Issuance of section 10 permit. Your construction activities are authorized through the issuance of a permit under section 10 of the ESA, and this authorization addresses the effects of the site’s discharges and discharge-related activities on federally-listed species and federally-designated critical habitat. You must include copies of the correspondence between yourself and the Services in your SWPPP and your NOI. For criterion C, provide the following information:  Refer to Attachment K for list of endangered species. 3.2 Historic Properties Screening Process Appendix E (of the CGP), Step 1 Do you plan on installing any of the following stormwater controls at your site? Check all that apply below, and proceed to Appendix E, Step 2. Dike Berm Catch Basin Pond Stormwater Conveyance Channel (e.g., ditch, trench, perimeter drain, swale, etc.) Culvert Other type of ground-disturbing stormwater control: Sewer Manhole, Drain Manhole, Area Drain, Bioretention If you will not be installing any ground-disturbing stormwater controls, no further documentation is required for Section 3.2 of the Template. Appendix E, Step 2 If you answered yes in Step 1, have prior cultural resource surveys or other evaluations determined that historic properties do not exist, or that prior disturbances at the site have precluded the existence of historic properties? YES NO If yes, provide documentation of the basis for your determination. If no, proceed to Appendix E, Step 3. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 13 3.3 Safe Drinking Water Act Underground Injection Control Requirements Do you plan to install any of the following controls? Check all that apply below. Infiltration trenches (if stormwater is directed to any bored, drilled, driven shaft or dug hole that is deeper than its widest surface dimension, or has a subsurface fluid distribution system); Commercially manufactured pre-cast or pre-built proprietary subsurface detention vaults, chambers, or other devices designed to capture and infiltrate stormwater flow; and Drywells, seepage pits, or improved sinkholes (if stormwater is directed to any bored, drilled, driven shaft or dug hole that is deeper than its widest surface dimension, or has a subsurface fluid distribution system) SECTION 4: EROSION AND SEDIMENT CONTROLS REQUIREMENTS Section 4 of this document describes the stormwater controls that will be implemented throughout construction. The operator must install and maintain all stormwater controls in compliance with Parts 2.2 and 2.3 of the CGP. The operator must install stormwater controls by the time construction activity in any givern portion of the site begins. The stormwater controls shall be designed and installed in accordance with good engineering practices and applicable design specifications. Specifications titled “312500- Erosion and Sedimentation Controls,” dated 11/01/2023 and prepared by Nitsch Engineering and details titled “Erosion and Sedimentation Control Details,” dated 11/01/2023 and prepared by Nitsch Engineering have been provided to the contractor under separate cover. 4.1 Natural Buffers or Equivalent Sediment Controls Buffer Compliance Alternatives Are there any surface waters within 50 feet of your project’s earth disturbances? YES NO (Note: If no, no further documentation is required for Part 4.1 in the SWPPP Template. Continue to Part 4.2.) 4.2 Perimeter Controls General The site will be enclosed by a temporary construction fence as shown on the Erosion and Sedimentation Control Plan in Attachment A. Construction gates will be located at the entrance to the site as shown on the Erosion and Sedimentation Control Plan and all entrances will have stabilized construction entrances. All gates and entrances to the site will be secured during non-working hours. The areas of the site that will receive pollutant discharges will be surrounded by a Specific Perimeter Control listed below as shown on the Erosion and Sedimentation Control Plan in Attachment A. Sediment tracked offsite must be removed by the end of the same workday. Specific Perimeter Controls Perimeter Control # 1 · BMP Description: Silt Fence. · Installation Schedule: Prior to the Start of Construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 14 greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as described in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Perimeter Control # 2 · BMP Description: Silt Fence with Wattles. · Installation Schedule: Prior to the Start of Construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as described in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Perimeter Control # 3 · BMP Description: Super Silt Fence. · Installation Schedule: Prior to the Start of Construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as described in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Perimeter Control # 4 · BMP Description: Wattles. · Installation Schedule: Prior to the Start of Construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as described in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Perimeter Control # 5 · BMP Description: Silt Fence with Straw Bales. · Installation Schedule: Prior to the Start of Construction and/or immediately after stockpile is established. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 15 · Responsible Staff: Construction Manager and Site Contractor(s). 4.3 Sediment Track-Out General Gates will be located as shown on the Erosion and Sedimentation Control Plan in Attachment A to allow for construction vehicle access. Construction access points will have a stabilized construction entrance station or wheel wash station to minimize the track-out of sediment onto off-site streets, other paved areas, and sidewalks from vehicles exiting the construction site. Where sediment has been tracked out from your site onto paved roads, sidewalks, or other paved areas outside of your site, remove the deposited sediment by the end of the same business day in which the track-out occurs or by the end of the next business day if track-out occurs on a non- business day. Remove the track-out by sweeping, shoveling, or vacuuming these surfaces, or by using other similarly effective means of sediment removal. You are prohibited from hosing or sweeping tracked out sediment into any stormwater conveyance, storm drain inlet, or water of the U.S. Specific Track-Out Controls Track-Out Control # 1 · BMP Description: Street Sweeping. · Installation Schedule: Start of construction. · Inspection Schedule: The areas adjacent to the site should be inspected daily to determine if street sweeping is required. · Responsible Staff Construction Manager and Site Contractor(s). Track-Out Control # 2 · BMP Description: Stabilized Construction Entrance. · Installation Schedule: Start of construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as described in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). Track-Out Control # 3 · BMP Description: Wheel Wash Station. · Installation Schedule: Start of construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective. condition as described in part 2.1.4 of the CGP(s). The operator must provide an effective means of minimizing the discharge of pollutants from equipment and vehicle washing, wheel wash water, and other types of wash waters. The operator must ensure there is no discharge of soaps, solvents, or detergents in equipment and vehicle wash water. For storage of soaps, detergents, or solvents, the operator shall provide either a cover to minimze the exposure of these detergents to precipitation and to stormwater, or a similarily effective means designed to minimze discharge of pollutants from these areas. · Responsible Staff: Construction Manager and Site Contractor. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 16 4.4 Stockpiled Sediment or Soil General All soil stockpiles will be located outside of any natural buffers and away from existing and proposed catch basins and area drains and outside of proposed infiltration system footprints. A sediment barrier shall be installed along all downgradient perimeter areas. Examples of sediment barriers include silt fence, super silt fence, or wattles. You are prohibited from hosing down or sweeping soil or sediment accumulated on pavement or other impervious surfaces into any stormwater conveyance, storm drain inlet, or water of the U.S. For stockpiles that will be unused for 14 or more days, a cover such as a tarp or blown straw shall be provided or temporary stabilization should be provided (consistent with Part 2.2.14 of the CGP). Exposure while adding or removing materials from a pile shall be minimized. Specific Stockpile Controls Stockpile Control # 1 · BMP Description: Silt Fence. · Installation Schedule: Immediately after stockpile is established. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Stockpile Control # 2 · BMP Description: Wattles. · Installation Schedule: Immediately after stockpile is established. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Stockpile Control # 3 · BMP Description: Tarp. · Installation Schedule: When stockpile will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 17 Stockpile Control # 4 · BMP Description: Straw Bales. · Installation Schedule: Immediately after stockpile is established. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Stockpile Control # 5 · BMP Description: Blown Straw. · Installation Schedule: When stockpile will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). Stockpile Control # 6 · BMP Description: Hydroseeding. · Installation Schedule: When stockpile will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). 4.5 Minimize Dust General Disturbed land will be temporarily stabilized as required by the CGP. Dust will be minimized using measures including sprinkling/irrigation, vegetative cover, mulch, and/or stone. Stockpiles will be handled in accordance with section 4.4 of the SWPPP. Earth-disturbing activities are considered temporarily ceased when work will not resume for a period of 14 or more calendar days. Stabilization shall be initiated when earth-disturbing activities are temporarily or permanently ceased. Stabilization activities shall be complete within 14 calendar days after the initiation of soil stabilization measures. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 18 Specific Dust Controls Dust Control # 1 · BMP Description: Sprinkling/Irrigation. · Installation Schedule: As needed throughout earthwork activities as determined by the site contractor and construction manager. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). Dust Control # 2 · BMP Description: Straw or Mulch. · Installation Schedule: As needed throughout earthwork activities as determined by the site contractor and construction manager. When disturbed land will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). 4.6 Minimize the Disturbance of Steep Slopes General Steep slopes are defined as slopes of 15% or greater in grade. No steep slopes are proposed as part of this project. The EPA notes that the requirement to minimize disturbances to steep slopes does not apply to the creation of stockpiles. Specific Steep Slope Controls Steep Slope Control # 1 · BMP Description: Straw or Mulch. · Installation Schedule: When disturbed land will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective. condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). Steep Slope Control # 2 · BMP Description: Hydroseeding. · Installation Schedule: When disturbed land will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 19 greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). Steep Slope Control # 3 · BMP Description: Soil Stabilization Mats. · Installation Schedule: When disturbed land will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). Steep Slope Control # 4 · BMP Description: Rip-Rap. · Installation Schedule: When disturbed land will remain inactive for 14 or more calendar days. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). 4.7 Preserve Native Topsoil Onsite native topsoil shall be preserved, unless infeasible. Preserving native topsoil is not required where the intended function of a specific area of the site dictates that the topsoil be disturbed or removed. Stockpiling topsoil at off-site locations or transferring topsoil to other locations is an example of a way to preserve native topsoil. The contractor shall perform construction sequencing such that earth materials are exposed for a minimum of time before they are covered, seeded, or otherwise stabilized. 4.8 Minimize Soil Compaction General In areas where infiltration practices will be installed or areas of the site where final vegetative stabilization will occur, soil compaction shall be minimized. This includes restricting vehicle access and equipment use. Areas used for post-construction infiltration shall be constructed after all ground surfaces are fully stabilized when feasible. If proposed infiltration areas are constructed prior to the site being fully stabilized, additional erosion controls shall be installed. All stockpiled and material storage areas shall be located outside of the areas proposed for post-construction infiltration. Areas of post-construction landscaping shall be constructed after all ground surfaces are fully stabilized. If proposed landscaped areas are constructed prior to the site being fully stabilized, additional erosion controls shall be DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 20 installed. All soil stockpiles and material storage areas shall be located outside of the areas proposed for post- construction landscaping where feasible. Where this is not feasible, use techniques that rehabilitate and condition the soils as necessary to support vegetative growth prior to planting. 4.9 Storm Drain Inlets General All existing and proposed storm drain inlets affected by construction activities should be protected using an Inlet Sediment Filter as shown on the Erosion and Sedimentation Control Plan provided in Attachment A. Clean or remove and replace the protection measures as sediment accumulates, the filter becomes clogged, and/or performance is compromised. Where there is evidence of sediment accumulation adjacent to the inlet protection measure, remove the deposited sediment by the end of the same business day in which it is found or by the end of the following business day if removal by the same business day is not feasible. Specific Storm Drain Inlet Controls Storm Drain Inlet Control # 1 · BMP Description: Inlet Sediment Filter. · Installation Schedule: Prior to the Start of Construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective. condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). Storm Drain Inlet Control # 2 · BMP Description: Inlet Protection with Gravel. · Installation Schedule: Prior to the Start of Construction . · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). Storm Drain Inlet Control # 3 · BMP Description: Inlet Protection with Block and Gravel. · Installation Schedule: Prior to the Start of Construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 21 4.10 Minimize Erosion of Stormwater Conveyances There are no proposed stormwater conveyance channels associated with this project. 4.11 Sediment Basins There are no proposed sediment basins associated with this project. 4.12 Chemical Treatment There are no proposed chemical treatments associated with this project. 4.13 Dewatering Practices Dewatering isn’t expected to occur onsite. 4.14 Other Stormwater Controls Any changes in construction activity that that include means of stormwater control not included in this document will be identified, the SWPPP will be amended, and the appropriate erosion and sedimentation controls will be implemented. 4.15 Site Stabilization Initiate the installation of stabilization measures immediately in any areas of exposed soil where construction activities have permanently ceased or will be temporarily inactive for 14 or more calendar days. Complete the installation of stabilization measures as soon as practicable, but no later than X calendar days after stabilization has been initiated. Site Stabilization Practice #1 Vegetative Non-Vegetative Temporary Permanent · BMP Description: Soil Stabilization Mat. · Installation Schedule: As/if required. · Maintenance and Inspection: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Responsible Staff: Construction Manager and Site Contractor(s). Site Stabilization Practice #2 Vegetative Non-Vegetative Temporary Permanent · BMP Description: Temporary Seeding. · Installation Schedule: As/if required. · Maintenance and Inspection: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Responsible Staff: Construction Manager and Site Contractor(s). DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 22 SECTION 5: POLLUTION PREVENTION STANDARDS 5.1 Potential Sources of Pollution Potential sources of sediment to stormwater runoff: · Stockpiles and construction staging · Clearing and grubbing operations · Grading and site excavation · Topsoil stripping · Landscape operations · Soil tracking offsite from construction vehicles · Runoff from unstabilized areas · Construction debris Potential pollutants and sources, other than sediment, to stormwater runoff: · Combined Staging Area – fueling activities, equipment maintenance, sanitary facilities, and hazardous waste storage · Materials Storage Area – building materials, solvents, adhesives, paving materials, paints, aggregates, trash, etc. · Construction Activity-paving, curb installation, concrete pouring, and building construction Staging areas are shown on the Erosion and Sedimentation Control Plan provided in Attachment A. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 23 Construction Site Pollutants Pollutant-Generating Activity Pollutants or Pollutant Constituents (that could be discharged if exposed to stormwater) Location on Site (or reference SWPPP site map where this is shown) Pesticides (insecticides, fungicides, herbicides, rodenticides) Chlorinated hydrocarbons, organophosphates, carbonates, arsenic Herbicides used for noxious weed control Fertilizers Nitrogen, phosphorous Newly seeded areas Plaster Calcium sulphate, calcium carbonate, sulfuric acid Building construction Cleaning Solvents Perchloroethylene, methylene chloride, trichloroethylene, petroleum distillates No equipment cleaning allowed in project limits Asphalt Oil, petroleum distillates Streets and parking lots Concrete Limestone, sand pH, chromium Curb and gutter, sidewalk, building construction Glue, Adhesives Polymers, epoxies Building construction Paints Metal oxides, Stoddard solvent, talc, calcium carbonate, arsenic Building construction Curing compounds Naphtha Curb and gutter, building construction Wood preservatives Stoddard solvent, petroleum distillates, arsenic, copper, chromium Timber pads, bracing, building construction Hydraulic Oils/fluids Mineral oil Leaks/broken hoses from equipment Gasoline Benzene, ethyl benzene, toluene, xylene, MTBE Secondary containment/staging area Diesel Fuel Petroleum distillate, oil & grease, naphthalene, xylenes Secondary containment/staging area Kerosene Coal oil, petroleum distillates Secondary containment/staging area Antifreeze/coolant Ethylene glycol, propylene glycol, heavy metals (copper, lead, zinc) Leaks or broken hoses from equipment Sanitary toilets Bacteria, parasites, and viruses Staging area DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 24 5.2 Spill Prevention and Response BMP Description: Spill kit, vehicle washing, silt sack catch basin protection, silt fence Installation Schedule: Start of construction activity Maintenance and Inspection: Minimum weekly & as necessary Responsible Staff: Construction Manager and Site Contractor · Major vehicle maintenance onsite is prohibited · Re-fueling of vehicles within 25 feet of a drainage structure is prohibited · Spill kit shall be kept onsite consisting of: - Gloves - Absorbent mats - Drip pan Spill Prevention and Control Plan · Refer to contractor’s Spill Plan. · Manufacturers’ recommended spill control methods will be posted onsite and site personnel will be made aware of the requirements. · Cleanup supplies will be kept onsite in a materials storage area. This equipment will include: goggles, brooms, dustpans, mops, rags, gloves, oil absorbent, sawdust, plastic and metal trash cans, and other materials and supplies specifically designated for cleanup. · All spills will be immediately cleaned up after discovery. · The spill area will be well ventilated. · Cleanup personnel will wear suitable protective clothing. · Spills of toxic and/or hazardous material will be reported to state, local, and Federal authorities, as required by law. Spills shall also be reported immediately to the owner. · A spill incident report will be filed detailing the amount and extent of the spill, material(s) involved, and effectiveness of the cleanup. This report will be on file at the Construction Manager/Site Contractor office, as well as kept onsite in the field office. A copy shall also be filed with the Hazard Communication Coordinator (HCC). The Construction Manager/Site Contractor will designate someone onsite that will serve as the Spill Cleanup Coordinator. At least two other personnel will be designated as alternate spill coordinators. All spill control personnel will be trained in spill prevention, control, and cleanup. The names of the responsible personnel will be posted at the jobsite office of the Construction Manager/ Site Contractor. 5.3 Fueling and Maintenance of Equipment or Vehicles General Minor vehicle and equipment emergency maintenance can be performed onsite away from drainage structures. Major vehicle and equipment maintenance must be performed offsite. Equipment/vehicle storage areas and any onsite fuel tanks will be inspected weekly and after storm events. Equipment and vehicles will be inspected for leaks, equipment damage, and other service problems on each day of use. Any leaks will be repaired immediately or the equipment/vehicle will be removed from the site. Minor vehicle and equipment emergency maintenance shall occur when a vehicle cannot be safely removed from the site. The vehicle should be repaired so it can be taken off-site so that the rest of the maintenance can occur. Major vehicle maintenance onsite is prohibited. Re-fueling or maintenance of vehicles within 25 feet of a drainage structure shall be prohibited. Drip pans, drip cloths, or absorbent pads should be used when replacing spent fluids. Secondary containment and cover should be provided where appropriate. The fluids should be collect and stored prior to being disposed of offsite. Spill kits should be readily available. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 25 Specific Pollution Prevention Practice #1 · BMP Description: Spill Kit. · Installation Schedule: Onsite throughout construction. · Responsible Staff: Construction Manager and Site Contractor. Specific Pollution Prevention Practice #1 · BMP Description: Drip Pans, Drip Cloths, Absorbent Pads. · Installation Schedule: Onsite throughout construction. · Responsible Staff: Construction Manager and Site Contractor. 5.4 Washing of Equipment and Vehicles General Vehicle and equipment washout areas shall be constructed by the contractor away from receiving water and storm drain inlets or constructed or natural site drainage features so that no untreated water enters the storm drain system. Soaps, detergents, or solvents must be stored in a way to prevent these detergents from coming into contact with rainwater, or a similarly effective means designed to prevent the discharge of pollutants from these areas. Specific Pollution Prevention Practices Pollution Prevention Practice # 1 · BMP Description: Designated vehicle/equipment washing areas · Installation Schedule: Start of construction. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Responsible Staff: Construction Manager and Site Contractor Pollution Prevention Practice # 2 · BMP Description: Spill kit, vehicle washing, straw bale catch basin protection, silt fence · Installation Schedule: Start of construction activity · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Responsible Staff: Construction Manager and Site Contractor 5.5 Storage, Handling, and Disposal of Construction Products, Materials, and Wastes 5.5.1 Building Products General The contractor will recycle all construction materials possible. For materials that cannot be recycled, solid waste will be disposed of in accordance with DEP Regulations for Solid Waste Facilities, 310 CMR 10.00. Any building materials required to be stored onsite will be stored at a combined staging and materials storage area as shown on the CMP. Larger items will be elevated by appropriate methods to minimize contact with runoff. The DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 26 storage area will be inspected weekly and after storm events. It will be kept clean, organized, and equipped with appropriate cleaning supplies. Building product usage shall follow the following good housekeeping BMPs: · The Responsible Staff: Construction Manager or Site Contractor representative will inspect daily for inspection of the work area to ensure proper management of waste materials. · Store only enough material onsite required for that job as to satisfy current construction needs. · Store required materials in tightly lidded containers under cover. · Store materials in original containers with clearly legible labels. · Separate and store materials apart from each other. · Do not mix materials unless specifically in accordance with manufacturers’ recommendations. · Use all products from a container before disposing of the container. · Follow manufacturers’ instructions for handling, storage, and disposing of all materials. · All materials shall be stored in an area to prevent the discharge of pollutants from building products. Specific Pollution Prevention Practices Pollution Prevention Practice # 1 · BMP Description: Perimeter Protection control around Stockpiles. · Installation Schedule: Start of construction/ Immediately after stockpile is established. · Inspection Schedule: Once every 14 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. Remove any sediment before it has accumulated to one-half of the above-ground height of any perimeter control. · Responsible Staff: Construction Manager and Site Contractor(s). 5.5.2 Pesticides, Herbicides, Insecticides, Fertilizers, and Landscape Materials · In storage areas, provide either (1) cover to minimize the exposure of these chemicals to precipitation and to stormwater or (2) a similarly effective means designed to minimize the discharge of pollutants from these areas. · Comply with all application and disposal requirements included on the registered pesticide, herbicide, insecticide, and fertilizer label. 5.5.3 Diesel Fuel, Oil, Hydraulic Fluids, Other Petroleum Products, and Other Chemicals General · Only skilled personnel in a designated area will perform fueling of vehicles onsite. · Vehicles used onsite will be monitored for fuel and oil leaks. · Vehicles used onsite will be maintained in good working order. · Asphalt substances will be applied in accordance with manufacturers’ recommendations. · The use of petroleum products as a release agent for asphalt transport trucks is prohibited. · Vehicle fueling will only be done in vehicle fueling areas located by the contractor. See section 5.3 of the SWPPP. · The contractor shall be responsible for locating the fuel storage and re-fueling area onsite to minimize disturbance to construction activates and site area. · Construction equipment not in active use for 5 minutes or more will be turned off. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 27 5.5.4 Hazardous or Toxic Waste (Note: Examples include paints, solvents, petroleum-based products, wood preservatives, additives, curing compounds, acids.) General · Keep products in their original containers. · Original container labels should be clearly visible. · Material safety data sheets will be kept onsite and be available. · Follow all state, local, and Federal regulations regarding the handling, use, storage, and disposal of hazardous material. Paints: · All paint containers will be tightly sealed when not in use. · Remove excess paint in original labeled containers from the jobsite. · Paint will not be disposed of onsite. Remove excess paint material from the site and legally dispose of. · Paint shall not be disposed of in the storm drain system. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 28 5.5.5 Construction and Domestic Waste General The contractor will manage domestic waste onsite. The contractor will provide waste containers of sufficient size and number to contain construction and domestic wastes. The waste container lids will be kept closed when not in use and lids will be closed at the end of the business day for those containers that are actively used throughout the day. For waste containers that do not have lids, provide either a cover or a similarly effective means designed to minimize discharge of pollutants. Clean up immediately if containers overflow. Pollution Prevention Practice # 1 · BMP Description: Dumpster. · Installation Schedule: Start of construction. · Maintenance and Inspection: Weekly and covered daily. · Responsible Staff: Construction Manager and Site Contractor(s). Pollution Prevention Practice # 2 · BMP Description: Litter/debris pick-up. · Installation Schedule: Start of construction. · Maintenance and Inspection: Daily. · Responsible Staff: Construction Manager and Site Contractor(s). 5.5.6 Sanitary Waste All sanitary waste portable toilets shall be positioned so that they are secure and will not be tipped or knocked over, and located away from any stormwater inlets or conveyances. Pollution Prevention Practice # 1 · BMP Description: Porta John. · Installation Schedule: Start of construction. · Maintenance and Inspection: As manufacturer requires. · Responsible Staff: Construction Manager and Site Contractor(s). 5.6 Washing of Applicators and Containers used for Paint, Concrete, or Other Materials General Washing of applicators and containers used for paint, concrete, or other materials shall follow the following good housekeeping BMPs: · An effective means of eliminating the discharge of water from the washout and cleanout of stucco, paint, concrete, form release oils, curing compounds, and other construction materials. · All washwater must be directed into a leak-proof container or leak-proof pit. The container or pit must be designed so that no overflows can occur due to inadequate sizing or precipitation. · Washout and cleanout wastes should be handled as follows: ― Do not dump liquid wastes into storm sewers. ― Dispose of liquid wastes in accordance with applicable requirements. ― Remove and dispose of hardened concrete waste consistent with the handling of other construction wastes. · Locate any washout or cleanout activities as far away as possible from surface waters and stormwater inlets or conveyances, and to the extent practicable, designate areas to be used for these activities and conduct such activities only in these areas. DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 29 Pollution Prevention Practice # 1 · BMP Description: Designated applicator and container washing areas. · Installation Schedule: Start of construction. · Maintenance and Inspection: Daily. · Responsible Staff: Construction Manager and Site Contractor(s). 5.7 Fertilizers General If fertilizer is required onsite, installation will follow the following guidelines: · Fertilizers will be used at the application rates called for in the specifications for the project. · Once applied, fertilizer will be worked into the soil to minimize wash off from irrigation and stormwater. · Fertilizer will be stored under cover. · The contents of partially used fertilizer bags will be transferred to re-sealable, watertight containers clearly labeled with their contents. · Avoid applying before heavy rains. · Never apply to frozen ground. · Never apply to stormwater conveyance channels with flowing water. 5.8 Other Pollution Prevention Practices Any changes in construction activity that produce other allowable non-stormwater discharges will be identified, the SWPPP will be amended and the appropriate erosion and sedimentation controls will be implemented. Control # X · BMP Description: Description of control to be installed. · Installation Schedule: Approximate date of installation. · Inspection Schedule: Pick Inspection schedule from above. · Maintenance: Ensure that all stormwater controls remain in effective condition as decribed in part 2.1.4 of the CGP. · Responsible Staff: Construction Manager and Site Contractor(s). DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 30 SECTION 6: INSPECTION, MAINTENANCE, AND CORRECTIVE ACTION 6.1 Inspection Personnel and Procedures Personnel Responsible for Inspections Construction Manager Contact Person Site Contractor Contact person (Note: All personnel conducting inspections must be considered a “qualified person.” CGP Part 4.1.1 clarifies that a “qualified person” is a person knowledgeable in the principles and practices of erosion and sediment controls and pollution prevention, who possesses the skills to assess conditions at the construction site that could impact stormwater quality, and the skills to assess the effectiveness of any stormwater controls selected and installed to meet the requirements of this permit.) Inspection Schedule Specific Inspection Frequency The contractor shall inspect and maintain erosion control measures, and remove sediment therefrom, once every 7 days and within 24 hours of a storm event 0.25” or greater and within 24 hours of a snowmelt from a storm event that produces 3.25 inches or more of snow. Rain Gauge Location: (USGS) Latitude 42º 23' 36'', Longitude 72º 14' 21'' NAD83 Worcester County, Massachusetts Hydrologic Unit 01080204 Reductions in Inspection Frequency (if applicable): Inspection frequency may be reduced to twice per month (no more than 14 days apart) for the first month in areas of the site where the stabilization steps outlines in Parts 2.2.14 of the CGP have been completed. After the first month, inspection frequency may be reduced to once per month. If construction activity resumes in this portion of the site at a later date, the inspection frequency immediately increases to that required in Parts 4.2 and 4.3 as applicable. You must document the beginning and ending dates of this period in the SWPPP. Inspection frequency may be reduced to once per month and within 24 hours of the occurrence of a storm event of 0.25 inches or greater if the project is located in an arid, semi-arid, or drought-stricken area and construction is occurring during the seasonally dry period or a period in which drought is predicted to occur. If this inspection frequency is followed, you must document the beginning and ending dates of this period in the SWPPP. Inspections can be temporarily suspended under the following conditions: · Earth-disturbing activity is suspended due to frozen condition; · Runoff is unlikely due to continuous frozen conditions that are likely to continue at the site for at least three months based on historic seasonal averaged. If unexpected weather conditions make discharges likely, the operators must immediately resume the regular inspection schedule; DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 31 · Land disturbances have been suspended; and · All disturbed areas of the site have been stabilized in accordance with Part 2.2.14a of the CGP. Inspection frequency may be reduced to once per month under the following conditions: · The operator is still conducting earth disturbing activities under frozen conditions; · Runoff is unlikely due to continuous frozen conditions that are likely to continue at the site for at least three months based on historic seasonal averages. If unexpected weather conditions make discharges likely, the operator must immediately resume the regular inspection schedule; and · Except for areas in which the operator is conducting earth-disturbing activities, disturbed areas of the site have been stabilized in accordance with Part 2.2.14a of the CGP. Inspection Report Forms Copies of inspection reports are in Attachment D. 6.2 Corrective Action Personnel Responsible for Corrective Actions Contact Person, Construction Manager Company Contact Person, Site Contractor Corrective Action Forms A copy of the Corrective Action Form is in Attachment E. 6.3 Delegation of Authority Duly Authorized Representative(s) or Position(s): Construction Manager Company Contact Person Contact Person Title Street Address Town/City, State Zip Code xxx-xxx-xxxx Email address DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 32 SECTION 7: SWPPP TRAINING DOCUMENTATION Refer to Attachment I for a Training Log to be completed for each SWPPP training session. Refer to Attachment I for certificates from completion of EPA Inspector course Table 7-1: Documentation for Completion of Training Name Date Training Completed DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 33 SECTION 8: CERTIFICATION AND NOTIFICATION Operator – Owner’s Representative I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I have no personal knowledge that the information submitted is other than true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Name: Title: Signature: Date: Operator – Construction Manager I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I have no personal knowledge that the information submitted is other than true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Name: Title: Signature: Date: DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 34 SECTION 9: TURBIDITY BENCHMARK MONITORING FOR DEWATERING DISCHARGES If required to comply with Part 3.3 turbidity benchmark monitoring requirements for discharging to sensitive waters, the following procedures will be followed. Procedures: Collecting and evaluating samples Describe how you will collect and evaluate samples Reporting results and keeping monitoring information records Describe how you will report results to EPA and keep monitoring information records Taking corrective action when necessary Describe how you will take corrective action when necesary Turbidity Meter: Type of turbidity meter Insert the type of turbidity meter Turbidity meter manuals and manufacturer instructions Insert a copy of any manuals and manufacturer instructions in Appendix N of this SWPPP Template. Coordinating Arrangements for Turbidity Monitoring (if applicable): Permitted operator name Insert operator name Permitted operator NPDES ID Insert operator NPDES ID Coordinating Arrangement Describe the coordinating arrangement including which parties are tasked with specifc responsibilities DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 35 [Repeat as necessary.] Alternate turbidity benchmark (if applicable – alternate benchmarks must be approved by EPA): Alternate turbidity benchmark (NTU) Insert alternate turbidity benchmark Data and documentation used to request the alternate benchmark Insert the data and documentation that was submitted to EPA to request the alternate benchmark DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center SWPPP ATTACHMENTS Attachment A – Site Maps Attachment B – 2022 Construction General Permit Attachment C – NOI and EPA Authorization Email Attachment D – Site Inspection Form and Dewatering Inspection Form (If Applicable) Attachment E – Corrective Action Form Attachment F – SWPPP Amendment Log Attachment G – Subcontractor Certifications/Agreements Attachment H – Grading and Stabilization Activities Log Attachment I – SWPPP Training Documentation Attachment J – Delegation of Authority Form Attachment K – Endangered Species Documentation Attachment L – Historic Preservation Documentation Attachment M – Rainfall Gauge Recording Attachment N – Turbidity Meter Manual and Manufacturer’s Instructions Attachment O – Order of Conditions DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment A – Site Maps DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment B – 2022 Construction General Permit DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment C – NOI and EPA Authorization Email DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment D – Site Inspection Form and Dewatering Inspection Form DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment E – Corrective Action Form DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment F – SWPPP Amendment Log DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center No. Description of the Amendment Date of Amendment Amendment Prepared by [Name(s) and Title] DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment G –Subcontractor Certifications/Agreements DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center SUBCONTRACTOR CERTIFICATION STORMWATER POLLUTION PREVENTION PLAN Project Number: Project Title: Operator(s): As a subcontractor, you are required to comply with the Stormwater Pollution Prevention Plan (SWPPP) for any work that you perform onsite. Any person or group who violates any condition of the SWPPP may be subject to substantial penalties or loss of contract. You are encouraged to advise each of your employees working on this project of the requirements of the SWPPP. A copy of the SWPPP is available for your review at the office trailer. Each subcontractor engaged in activities at the construction site that could impact stormwater must be identified and sign the following certification statement: I certify under the penalty of law that I have read and understand the terms and conditions of the SWPPP for the above designated project and agree to follow the practices described in the SWPPP. This certification is hereby signed in reference to the above named project: Company: Address: Telephone Number: Type of construction service to be provided: Signature: Title: Date: DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment H – Grading and Stabilization Activities Log DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Date Grading Activity Initiated Description of Grading Activity Description of Stabilization Measure and Location Date Grading Activity Ceased (Indicate Temporary or Permanent) Date When Stabilization Measures Initiated DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment I – SWPPP Training Documentation DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Stormwater Pollution Prevention Training Documentation Project Name: Project Location: Instructor’s Name(s): Instructor’s Title(s): Course Location: Date: Course Length (hours): Stormwater Training Topic: (check as appropriate)  Sediment and Erosion Controls  Emergency Procedures  Stabilization Controls  Inspections/Corrective Actions  Pollution Prevention Measures Specific Training Objective: Attendee Roster: (attach additional pages as necessary) No. Name of Attendee Company 1 2 3 4 5 6 7 8 DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 50 Attachment J – Delegation of Authority Form DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 51 Delegation of Authority I, _______________________ (name), hereby designate the person or specifically described position below to be a duly authorized representative for the purpose of overseeing compliance with environmental requirements, including the Construction General Permit, at the ____________________________________ construction site. The designee is authorized to sign any reports, stormwater pollution prevention plans and all other documents required by the permit. ________________________________________ (name of person or position) ________________________________________ (company) ________________________________________ (address) ________________________________________ (city, state, zip) ________________________________________ (phone) By signing this authorization, I confirm that I meet the requirements to make such a designation as set forth in Appendix I of EPA’s Construction General Permit (CGP), and that the designee above meets the definition of a “duly authorized representative” as set forth in Appendix I. I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Name: Company: Title: Signature: Date: DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment K – Endangered Species Documentation DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 53 Attachment L – Historic Preservation Documentation DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment M – Rainfall and Snowfall Gauge Recording Use the table below to record the rainfall and snowfall gauge readings at the beginning and end of each work day. An example table follows. Month/Year Month/Year Month/Year Day Start time End time Day Start time End time Day Start time End time 1 1 1 2 2 2 3 3 3 4 4 4 5 5 5 6 6 6 7 7 7 8 8 8 9 9 9 10 10 10 11 11 11 12 12 12 13 13 13 14 14 14 15 15 15 16 16 16 17 17 17 18 18 18 19 19 19 20 20 20 21 21 21 22 22 22 23 23 23 24 24 24 25 25 25 26 26 26 27 27 27 28 28 28 29 29 29 30 30 30 31 31 31 DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center 55 Attachment N – Turbidity Meter Manual and Manufacturer’s Instructions DRAFT Stormwater Pollution Prevention Plan Smith College Lazarus-Wurtele Center Attachment O – Order of Conditions 18 APPENDIX G Soil Investigations NRCS Soil Maps and Descriptions Geotechnical Report Soil Test Pit Logs HALEY & ALDRICH, INC. 465 Medford St. Suite 2200 Boston, MA 02129 617.886.7400 www.haleyaldrich.com MEMORANDUM 19 June 2023 File No. 204385-000 TO: Smith College Charlie Conant C: Thornton Tomasetti; Attn: Jamie Kirkland TenBerke Architects; Attn: Harsha Sharma, Joshua Wujek, Arthi Krishnamoorthy Consigli; Attn: Mari Creatini, Rich Scopelliti FROM: Haley & Aldrich, Inc. Rich Genovesi; Bradford Aldinger SUBJECT: Preliminary Geotechnical Guidance Lazarus-Wurtele Center, Smith College Northampton, MA This memorandum presents preliminary geotechnical guidance, before issuance of our geotechnical report, to help the design team advance their design efforts and help Consigli, the construction manager, advance their pricing efforts. The preliminary design and construction guidance provided below is based on the results of two recently completed test boring programs, during the periods of 15- 17 May and 7-8 June 2023, and our discussions with you and the project team. For your reference we have included the following attachments:  Draft copy of Figure 2 – Site and subsurface exploration location plan, dated June 2023.  Draft test boring logs.  A photograph of recently collected rock core. Preliminary Geotechnical Recommendations  Design groundwater level: El. 183  Foundation Type: As discussed in calls with the project team, we recommend evaluation of both shallow and deep foundations.  Shallow foundations: Footings and/or mat foundations – General considerations Smith College 19 June 2023 Page 2 ▪ Typically, less expensive. ▪ Technical feasibility will depend on the predicted settlements associated with the provided structural loads. ▪ Economic feasibility will depend on their relative costs due to the size required and cost of the foundations to accommodate the structural loads based on the allowable bearing pressure provided below. – Preliminary design considerations ▪ Assume a gross allowable bearing capacity of 1,500 psf (no net stress increase on the clay).  Deep foundations: H-piles, drilled micropiles (DMPs) – General considerations ▪ Typically, more expensive. ▪ If project design and pricing suggest that one or more of the conditions indicated below are true, deep foundations may be an advantageous approach: • Relatively high uplift pressures in the structure require tiedown anchors. • Relatively large shear forces in the structure require more efficient lateral load resistance. • Soil generated from pile caps is less than soil generated from shallow foundation excavations, resulting in lower soil transport fees and overall lower costs for the deep foundation approach. – Preliminary design considerations ▪ Driven H-Piles – Provided there are no settlement sensitive receptors nearby and the potential disruption to campus students, personnel, and activities from their installation is acceptable, driven H-Piles appear feasible. ▪ Initial recommendations for pricing of common pile sizes used for lightly loaded structures are below: • HP10x42: 75 ton compression, 15 ton tension, approximate tip at El. 125. • HP12x74: 170 ton compression, 20 ton tension, approximate tip at El. 125. • We have assumed: o minimum yield stress of 50 ksi; o 1/16 in. corrosion around the pile perimeter; o drive shoes on the pile; and o load test required. ▪ Drilled Micropiles • Assume: Smith College 19 June 2023 Page 3 o 100-ton compression, 50 ton tension o 7 in. dia. pile with permanent steel casing advanced 1 ft into bedrock and a 12 ft rock socket. o Pile tip elevation roughly El. 115. o Allowable skin friction in the rock of 70 psi. o Pile load test or successful waiver needed.  Seismic Design (using Mass Building code 10th Edition): – Site Class D, Ss= 0.167g, S1= 0.056g. – Site soils not considered liquefaction susceptible during the Code design earthquake.  Lateral Pressures – Design new building foundation walls serving as retaining walls in accordance with the applicable below-listed lateral pressures. – The recommendations assume that the walls are drained full height, including a perimeter drain at the base of the wall, and grades behind the wall are flat to a horizontal distance behind the wall equal to the height of the wall (H). – The height of the wall (H) is herein defined as the distance in feet between the top of upper finished floor level (or finished site grade) on the retained earth side of the wall and the bottom of the lower finished floor level (or finished site grade) on the down- slope side of the wall. – For seismic loading conditions, walls should be designed to resist static plus seismic earth pressures. Surcharge loading does not need to be considered for seismic design unless the surcharge will be applied over an extended time. – Static Earth: ▪ Restrained walls ((braced at the top and bottom): Equivalent fluid unit weight equal to 60 pounds per square foot (psf) per foot depth applied to the bottom of the foundation element. ▪ Unrestrained walls (walls that are free to deflect at the top of the wall): Equivalent fluid unit weight equal to 40 psf per foot depth applied to the bottom of the foundation element. – Seismic Earth: ▪ Inverted triangular pressure applied over the height of the wall (H) with a magnitude of 8.3H (psf) at the top of the wall. – Surcharge: ▪ Uniform pressure applied from the elevation of the surcharge to the bottom of the foundation element with a magnitude of 0.5q or 0.3q (psf), where q is the vertical surcharge load (psf), uniformly distributed over the height of the wall for restrained and unrestrained walls, respectively. Smith College 19 June 2023 Page 4 – Foundation walls designed as retaining walls should be designed for a factor of safety of 1.5 against sliding and overturning under static loading conditions and 1.2 under seismic loading conditions. – Passive soil pressure should not be included as a resisting force.  Resistance to Lateral Loads (for shallow foundations) – Lateral loads may be resisted using a combination of friction between footing bases and underlying bearing materials, and passive restraint on the sides of footings and walls. – The resistance to lateral loads provided by friction between footing concrete and underlying Lacustrine Clay Deposits should be calculated using a coefficient of friction (ultimate) equal to 0.3. Lateral capacities for pile supported structure will be provided in our forthcoming geotechnical report.  Temporary Lateral Earth Support, SOE, system – Preliminarily, we recommend assuming steel sheeting driven some depth into the clay, to cut off groundwater, or deeper as contractor designer deems necessary. – Soil nail wall: Preliminary analyses indicate a soil nail wall would be challenged from a global slope stability perspective (FS < 1 for assumed soil properties), leading to undesirable movements of the wall and behind it. – All things being equal, and assuming a soil nail wall is not feasible, it is likely that steel sheeting would be the least expensive option. We would be happy to work directly with Thornton Tomasetti on specific aspects of design (e.g., lateral load analysis for piles, etc.) as required to complete their structural analysis. Please do not hesitate to contact us for specific information requests. Feel free to contact us with questions. Attachments Figure 2 – Site and subsurface exploration location plan, dated June 2023 Draft test boring logs Photograph of recently collected rock core \\haleyaldrich.com\share\CF\Projects\0204385\Deliverables\Prelim-GT-Guidelines\2023-0619-HAI-M-Smith-Laz-Wurtele-Prelim-Geotech-D1.docx HA23-1HA23-2HA23-6 (OW)HA23-3 (OW)HA23-4HA23-5185.5178.5145.0<145187.5181.5147.5<143.5190.5184.5150.5125.5188.0179.0157.0128.0184.0175.0<174<174192.0176.0<161<161LEGENDDESIGNATION AND APPROXIMATE LOCATION OFTEST BORING DRILLED BY SEABOARD DRILLING, LLCDURING THE PERIOD OF 15 MAY TO 9 JUNE 2023EL. GROUND SURFACEEL. TOP OF LACUSTRINE CLAYEL. TOP OF GLACIAL TILLEL. TOP OF BEDROCKNOTES1.BASE PLAN IS PDF OF DRAWING C-500 TITLED "ROADWAY LAYOUTPLAN" PREPARED BY NITSCH ENGINEERING DATED 10 MAY 2023.03060SCALE IN FEET\\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\CAD\0204385 - BLP.DWGRGENOVESIHA-FIG-B-L-H6/19/2023 2:24 PM Sheet:Printed:FIGURE 2LAZARUS-WURTELE CENTERSMITH COLLEGENORTHAMPTON, MASSACHUSETTSSITE AND SUBSURFACEEXPLORATION LOCATION PLANSCALE: AS SHOWNJUNE 2023HA23-1188.0179.0140.0125.0Draft Print06/19/2023 5:11:49 PM S1 12 S2 18 S315 S420 S520 S6 24 0.0 2.0 2.0 4.0 5.0 7.0 7.0 9.0 10.0 12.0 15.0 17.0 3322 2 222 5655 4546 32 1 2 WOH WOHWOHWOH SM SP- SM SP- SM ML CL CL 15 15 25 35 50 45 5 15 20 15 10 15 15 10 10 90 80 100 15 5 5 50.0 0.0 0.0 0.0 0.0 185.20.3 183.52.0 178.57.0 175.510.0 -BITUMINOUS CONCRETE PAVEMENT- Loose brown silty SAND with gravel (SM), mps 0.25 in., no structure, no odor, moist Very loose red-brown poorly graded SAND with silt (SP-SM), mps 0.25 in., weak structure, no odor, moist Medium dense red-brown poorly graded SAND with silt (SP-SM), mps 0.25 in., weak structure, no odor, moist -FILL- Loose dark gray SILT (ML), no structure, no odor, wet Soft gray lean CLAY (CL), no odor, moist Very soft dark gray lean CLAY (CL), no odor, wet -LACUSTRINE DEPOSITS- 7 File No. 42.0 Location HA23-1 Time (hr.) 5/15/2023 Inside Diameter (in.)None Boring No. Driller Datum Type Barrel Rig Make & Model: Grout Screen Well Diagram Sheet No. 15 May 2023 of Hole 30 1 3/8 - Elapsed Riser Pipe Start Bit Type:S H&A Rep. Plasticity: N - Nonplastic L - Low M - Medium H - HighDry Strength: N - None L - Low M - Medium H - High V - Very High Drilling 0204385-000 See Plan NAVD88 30 Summary Field Tests: 2 Drill Mud: Hammer Weight (lb)-140140 Date Bottom Filter Sand Dilatancy: R - Rapid S - Slow N - NoneToughness: L - Low M - Medium H - High Cuttings MiniRAE 2000 10.6 eV HA23-1 Samples S11 Water Concrete Hammer Fall (in.) Bentonite Seal Finish Elevation - of Casing Bottom Spun Winch Automatic Hammer Time Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Sample ID Boring No. J. NitshDrilling Equipment and Procedures 15 May 20231 Truck T. Danaher Casing Casing: PID Make & Model: Hoist/Hammer: - Depth (ft) to: Sampler Overburden (ft) Rock Cored (ft) of HSA Cutting Head O - Open End Rod T - Thin Wall Tube U - Undisturbed Sample S - Split Spoon Sample 3.25 - 185.5 (est.) †Note: Maximum particle size is determined by direct observation within the limitations of sampler size. Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)0 5 10 15 20 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptionsGEOLOGIC INTERPRETATION) S724 S824 S9 24 S1024 S1120 20.0 22.0 25.0 27.0 30.0 32.0 35.0 37.0 40.0 42.0 WOHWOHWOHWOH 2 1 11 WOHWOHWOHWOH WOHWOHWOHWOH WOH 3 9 14 CL CL CL CL SM 5 10 70 100 100 100 100 15 0.0 0.0 0.0 0.0 0.0 145.040.5 143.542.0 Similar to S6 Similar to S7 Similar to S8 Similar to S9 -LACUSTRINE DEPOSITS- Medium dense red-brown silty SAND (SM), mps 3 mm, no structure, no odor, wet -GLACIAL TILL- BOTTOM OF EXPLORATION 42.0 FT File No. Boring No.HA23-1 Sheet No. HA23-1 2of2 NOTE: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Boring No. 0204385-000 Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)20 25 30 35 40 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptions GEOLOGIC INTERPRETATION) S1 10 S2 16 S318 S424 S522 S6 24 0.0 2.0 2.0 4.0 5.0 7.0 7.0 9.0 10.0 12.0 15.0 17.0 4343 3 545 4745 3338 24 6 6 WOH WOHWOHWOH SP- SM SP SP ML-CL SM CL 15 5 5 5 50 15 15 5 5 25 10 75 75 15 15 45 10 5 5 80 80 25 100 1050.0 0.0 0.0 0.0 0.0 0.0 187.10.4 185.52.0 181.56.0 177.510.0 172.515.0 -ASPHALT- Loose red-brown poorly graded SAND with silt and gravel (SP-SM), mps 0.25 in., weak structure, no odor, moist Loose light brown poorly graded SAND (SP), mps 4 mm, weak structure, no odor, moist -FILL- Similar to S2, except medium dense Meidum stiff olive-brown to gray-brown sandy SILT (ML) interbedded with silty CLAY (CL), mps 0.1 mm, strong structure, no odor, moist to wet Similar to S3 below 6 ft Medium dense gray-brown to red-brown sitly SAND (SM), mps 0.25 in., no odor, wet Very soft gray-brown lean CLAY (CL), laminated, no odor, wet -LACUSTRINE DEPOSITS- 7 File No. 44.0 Location HA23-2 Time (hr.) 5/15/2023 Inside Diameter (in.)None Boring No. Driller Datum Type Barrel Rig Make & Model: Grout Screen Well Diagram Sheet No. 15 May 2023 of Hole 30 1 3/8 - Elapsed Riser Pipe Start Bit Type:S H&A Rep. Plasticity: N - Nonplastic L - Low M - Medium H - HighDry Strength: N - None L - Low M - Medium H - High V - Very High Drilling 0204385-000 See Plan NAVD88 30 Summary Field Tests: 2 Drill Mud: Hammer Weight (lb)-140140 Date Bottom Filter Sand Dilatancy: R - Rapid S - Slow N - NoneToughness: L - Low M - Medium H - High Cuttings MiniRAE 2000 10.6 eV HA23-2 Samples S12 Water Concrete Hammer Fall (in.) Bentonite Seal Finish Elevation - of Casing Bottom Spun Winch Automatic Hammer Time Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Sample ID Boring No. J. NitshDrilling Equipment and Procedures 15 May 20231 Truck T. Danaher Casing Casing: PID Make & Model: Hoist/Hammer: - Depth (ft) to: Sampler Overburden (ft) Rock Cored (ft) of HSA Cutting Head O - Open End Rod T - Thin Wall Tube U - Undisturbed Sample S - Split Spoon Sample 3.25 - 187.5 (est.) †Note: Maximum particle size is determined by direct observation within the limitations of sampler size. Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)0 5 10 15 20 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptionsGEOLOGIC INTERPRETATION) S724 S824 S9 24 S1024 S1115 S1218 20.0 22.0 25.0 27.0 30.0 32.0 35.0 37.0 40.0 42.0 42.0 44.0 WOHWOHWOHWOH WOH WOH WOHWOH WOHWOHWOHWOH WOHWOHWOHWOH 1 6 9 9 7 17 21 50 CL CL CL CL SM SM 10 10 50 50 15 15 100 100 100 100 15 15 5 5 5 5 0.0 0.0 0.0 0.0 0.0 0.0 147.540.0 143.544.0 Similar to S6 Similar to S7 Similar to S8 Similar to S9 -LACUSTRINE DEPOSITS- Medium dense gray-brown silty SAND (SM), mps 0.25 in., bonded, no odor, wet Similar to S11, except dense -GLACIAL TILL- Note: HSA refusal at 44 ft on probable boulder. BOTTOM OF EXPLORATION 44.0 FT File No. Boring No.HA23-2 Sheet No. HA23-2 2of2 NOTE: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Boring No. 0204385-000 Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)20 25 30 35 40 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptions GEOLOGIC INTERPRETATION) S1 11 S2 4 S38 S4 14 S514 S6 10 0.0 2.0 2.0 4.0 4.0 6.0 6.0 8.0 10.0 12.0 15.0 17.0 3323 2 222 2232 3466 57 8 7 1 2WOHWOH SP- SM SM SM SP- SM CL CL 5 5 5 70 45 45 70 15 25 25 20 10 20 20 10 100 100 5 5 0.0 0.0 0.0 0.0 0.0 0.0 190.20.3 188.52.0 184.56.0 180.510.0 -TOPSOIL- Loose dark brown poorly graded SAND with silt (SP-SM), mps 0.25 in., no structure, no odor, moist Loose dark brown silty SAND (SM), mps 0.25 in., no structure, no odor, moist Similar to S2 -FILL- Loose brown poorly graded SAND with silt (SP-SM), no structure, no odor, moist -GLACIOFLUVIAL DEPOSITS- Stiff gray lean CLAY (CL), no odor, wet Very soft gray-brown lean CLAY (CL), laminated, no odor, wet -LACUSTRINE DEPOSITS- File No. 65.0 Location HA23-3 Time (hr.) Inside Diameter (in.)None Boring No. Driller Datum Type Barrel Rig Make & Model: Grout Screen Well Diagram Sheet No. 17 May 2023 of Hole 30 1 3/8 NX Elapsed Riser Pipe Start Bit Type:S H&A Rep. Plasticity: N - Nonplastic L - Low M - Medium H - HighDry Strength: N - None L - Low M - Medium H - High V - Very High 0204385-000 See Plan NAVD88 24 Summary Field Tests: 4 Drill Mud: Hammer Weight (lb)-140300 Date Bottom Filter Sand Dilatancy: R - Rapid S - Slow N - NoneToughness: L - Low M - Medium H - High Cuttings MiniRAE 2000 10.6 eV HA23-3 Samples S14, C1 Water Concrete Hammer Fall (in.) Bentonite Seal Finish Elevation - of Casing Bottom Driven Winch Automatic Hammer Time Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Sample ID Boring No. J. NitshDrilling Equipment and Procedures 16 May 20231 Truck T. Danaher Casing Casing: PID Make & Model: Hoist/Hammer: 2.0 Depth (ft) to: Sampler Overburden (ft) Rock Cored (ft) of HW Roller Bit O - Open End Rod T - Thin Wall Tube U - Undisturbed Sample S - Split Spoon Sample 4.0 5.0 190.5 (est.) †Note: Maximum particle size is determined by direct observation within the limitations of sampler size. Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)0 5 10 15 20 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT Well DiagramStratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptionsGEOLOGIC INTERPRETATION) S720 S812 S9 22 S1024 S113 S12 0 20.0 22.0 25.0 27.0 30.0 32.0 35.0 37.0 40.0 40.3 45.0 45.2 WOHWOHWOHWOH WOH WOH WOHWOH WOHWOHWOHWOH WOHWOHWOHWOH 50/3" 50/2" CL CL CL CL 100 100 100 100 0.0 0.0 0.0 0.0 0.0 150.540.0 Similar to S6 Similar to S7 Similar to S8 Similar to S9 -LACUSTRINE DEPOSITS- Rock fragments in tip, mps 0.75 in. Note: Numerous cobbles and boulders from 41 to 50 ft. Difficult drilling. No recovery -GLACIAL TILL- File No. Boring No.HA23-3 Sheet No. HA23-3 4of2 NOTE: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Boring No. 0204385-000 Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)20 25 30 35 40 45 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT Well DiagramStratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptions GEOLOGIC INTERPRETATION) S13 3 S140 50.0 50.4 55.0 55.0 50/4" 50/0" 125.565.0 SM 15 25 15 2015100.0 Very dense gray silty SAND with gravel (SM), mps 1.0 in., weak structure, no odor, wet No recovery. Sampler appeared to bounce on probable cobble/boulder. Note: Advanced borehole to bedrock using a roller bit then drive casing into bedrock to faciliate collection of bedrock core. -GLACIAL TILL- SEE CORE BORING REPORT FOR ROCK DETAILS File No. Boring No.HA23-3 Sheet No. HA23-3 4of3 NOTE: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Boring No. 0204385-000 Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)50 55 60 65 70 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT Well DiagramStratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptions GEOLOGIC INTERPRETATION) C16.9 5.7 5.8 5.5 5.7 125.565.0 120.570.0 Hard, slightly weathered, red brown, fine to coarse grained SANDSTONE.Primary joint set: horizontal to low angle, very close to close, rough, discolored,open. -BEDROCK- BOTTOM OF EXPLORATION 70.0 FT 60 40 100 67 65.0 70.0 Recovery/RQD 300 S T. Danaher -30 2.0 NAVD88 17 May 2023 Winch, Automatic Hammer Casing: Sampler Type Sheet No.of See Plan Roller Bit HW Drilling Equipment and Procedures Driven Datum Elevation Location Start 140 - Truck Finish Hammer Weight (lb) Hammer Fall (in.) 16 May 2023 Rig Make & Model: 24 Driller Bit Type: None4.0 Drill Mud: Hoist/Hammer: Casing 1 3/8 H&A Rep. J. NitshBarrel NX File No. 4 HA23-3 Inside Diameter (in.) 0204385-000 Boring No. 190.5 (est.) 1 Bentonite Seal 65.0 5.0 GroutG - Geoprobe S - Split Spoon Boring No. Screen Summary Riser Pipe Water Depth (ft.) to:Time Bottom Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. U - Undisturbed Sample O - Open End Rod Sample Identification Well Diagram Overburden (lin. ft.)Elapsed HA23-3 T - Thin Wall Tube Rock Cored (lin. ft.) Concrete Cuttings Filter Sand S14, C1 of Casing Bottom of Hole Date Samples Time (hr.) Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA H+A CORE LOG PG1-07-1 HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-1.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 13 Jun 23CORE BORING REPORT Weath-eringRunNo. DrillingRate(min./ft) Depth(ft) 65 70 75 80 85 Well Dia- gram Elev./Depth(ft) Visual Descriptionand Remarksin. % Run Depth (ft) DRAFT S1 17 S2 14 S318 S4 19 S514 S6 20 0.0 2.0 2.0 4.0 4.0 6.0 6.0 8.0 8.0 10.0 15.0 17.0 23810 6 766 3653 1222 21 2 2 1 WOH1WOH SP- SM SP SP SM CL CL 15 5 5 5 5 50 25 25 25 25 10 65 65 45 45 10 5 5 25 25 100 100 1050.0 0.0 0.0 0.0 0.0 0.0 0.0 187.70.3 186.02.0 182.06.0 179.09.0 -BITUMINOUS CONCRETE PAVEMENT- Medium dense red-brown poorly graded SAND with silt and gravel, mps 0.75 in., no structure, no odor, moist Very loose brown poorly graded SAND (SP), mps 0.25 in., no structure, no odor, moist Similar to S2 -FILL- Very loose gray to gray-brown silty SAND (SM), weak structure, no odor, moist -GLACIOFLUVIAL DEPOSITS- Similar to S4 Medium stiff gray lean CLAY (CL), no odor, wet -LACUSTRINE DEPOSITS- Very soft gray-brown lean CLAY (CL), laminated, no odor, wet File No. 10 Location HA23-4 Time (hr.) Inside Diameter (in.)None Boring No. Driller Datum Type Barrel Rig Make & Model: Grout Screen Well Diagram Sheet No. 7 June 2023 of Hole 30 1 3/8 NX Elapsed Riser Pipe Start Bit Type:S H&A Rep. Plasticity: N - Nonplastic L - Low M - Medium H - HighDry Strength: N - None L - Low M - Medium H - High V - Very High 0204385-000 See Plan NAVD88 24 Summary Field Tests: 4 Drill Mud: Hammer Weight (lb)-140300 Date Bottom Filter Sand Dilatancy: R - Rapid S - Slow N - NoneToughness: L - Low M - Medium H - High Cuttings MiniRAE 2000 10.6 eV HA23-4 Samples S12 Water Concrete Hammer Fall (in.) Bentonite Seal Finish Elevation - of Casing Bottom Driven Winch Automatic Hammer Time Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Sample ID Boring No. J. NitshDrilling Equipment and Procedures 17 May 20231 Truck T. Danaher Casing Casing: PID Make & Model: Hoist/Hammer: 2.0 Depth (ft) to: Sampler Overburden (ft) Rock Cored (ft) of HW Roller Bit O - Open End Rod T - Thin Wall Tube U - Undisturbed Sample S - Split Spoon Sample 4.0 10 188.0 (est.) †Note: Maximum particle size is determined by direct observation within the limitations of sampler size. Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)0 5 10 15 20 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptionsGEOLOGIC INTERPRETATION) S724 S822 S9 19 S108 20.0 22.0 25.0 27.0 30.0 32.0 40.0 41.1 WOHWOHWOHWOH WOH WOH WOHWOH WOHWOH39 31 40 50/1" CL CL CL SW- SM SM 20 25 15 100 100 100 100 151015 0.0 0.0 0.0 0.0 0.0 157.031.0 Similar to S6 Similar to S7 Similar to S7 Medium dense red-brown to gray-brown well graded SAND with silt and gravel (SW- SM), mps 1 in., no structure, no odor, wet Note: Difficult drilling with numerous cobbles and boulders throughout glacial till stratum. Very dense gray-brown silty SAND with gravel, mps 1 in., moderately bonded in-situ, no odor, wet File No. Boring No.HA23-4 Sheet No. HA23-4 4of2 NOTE: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Boring No. 0204385-000 Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)20 25 30 35 40 45 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptions GEOLOGIC INTERPRETATION) S11 0 S128 50.0 50.1 55.0 55.8 50/1" 4050/4" 128.0 60.0 SM 20 25 15 1510150.0 No recovery Very dense gray-brown silty SAND with gravel, mps 1 in., moderately bonded in-situ, no odor, wet SEE CORE BORING REPORT FOR ROCK DETAILS File No. Boring No.HA23-4 Sheet No. HA23-4 4of3 NOTE: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Boring No. 0204385-000 Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)50 55 60 65 70 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptions GEOLOGIC INTERPRETATION) 128.0 60.0 118.0 70.0 6.4 7.3 7.3 6.5 6.6 7.5 7.5 7.2 6.3 8.0 Moderately hard, moderately weathered, red brown, medium to coarse grainedSANDSTONE. Primary joint set: horizontal to low angle, very close to close, rough,discolored, open. Moderately hard to hard, moderately to slightly weathered, red brown, fine to coarsegrained SANDSTONE. Primary joint set: horizontal to low angle, extremely close toclose, rough, discolored, open. -BEDROCK- BOTTOM OF EXPLORATION 70.0 FT 28 0 50 8 47 0 83 13 60.0 65.0 65.0 70.0 Recovery/RQD 300 S T. Danaher -30 2.0 NAVD88 7 June 2023 Winch, Automatic Hammer Casing: Sampler Type Sheet No.of See Plan Roller Bit HW Drilling Equipment and Procedures Driven Datum Elevation Location Start 140 - Truck Finish Hammer Weight (lb) Hammer Fall (in.) 17 May 2023 Rig Make & Model: 24 Driller Bit Type: None4.0 Drill Mud: Hoist/Hammer: Casing 1 3/8 H&A Rep. J. NitshBarrel NX File No. 4 HA23-4 Inside Diameter (in.) 0204385-000 Boring No. 188.0 (est.) 1 Bentonite Seal 10 10 GroutG - Geoprobe S - Split Spoon Boring No. Screen Summary Riser Pipe Water Depth (ft.) to:Time Bottom Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. U - Undisturbed Sample O - Open End Rod Sample Identification Well Diagram Overburden (lin. ft.)Elapsed HA23-4 T - Thin Wall Tube Rock Cored (lin. ft.) Concrete Cuttings Filter Sand S12 of Casing Bottom of Hole Date Samples Time (hr.) Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA H+A CORE LOG PG1-07-1 HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-1.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 13 Jun 23CORE BORING REPORT Elev./Depth (ft) Weath-eringRunNo. DrillingRate(min./ft) Depth(ft) 60 65 70 75 80 Visual Descriptionand Remarksin. % Run Depth (ft) DRAFT S1 17 S2 17 S316 S4 17 S520 0.0 2.0 2.0 4.0 4.0 6.0 6.0 8.0 8.0 10.0 8866 7 644 3332 2212 23 3 2 SP- SM SP SP SM CL 15 5 5 5 5 50 15 25 25 25 10 75 65 45 45 10 5 5 25 25 100 1050.0 0.0 0.0 0.0 0.0 0.0 183.70.3 182.02.0 178.06.0 175.09.0 174.010.0 -BITUMINOUS CONCRETE PAVEMENT- Medium dense red-brown poorly graded SAND with silt and gravel, mps 0.75 in., no structure, no odor, moist Loose light brown poorly graded SAND (SP), mps 0.25 in., no structure, no odor, moist Similar to S2 -FILL- Very loose gray to gray-brown silty SAND (SM), weak structure, no odor, moist -GLACIOFLUVIAL DEPOSITS- Similar to S4, except loose Medium stiff gray lean CLAY (CL), no odor, wet -LACUSTRINE DEPOSITS- BOTTOM OF EXPLORATION 10.0 FT File No. 10 Location HA23-5 Time (hr.) Inside Diameter (in.)None Boring No. Driller Datum Type Barrel Rig Make & Model: Grout Screen Well Diagram Sheet No. 17 May 2023 of Hole 30 1 3/8 -- Elapsed Riser Pipe Start Bit Type:S H&A Rep. Plasticity: N - Nonplastic L - Low M - Medium H - HighDry Strength: N - None L - Low M - Medium H - High V - Very High 0204385-000 See Plan NAVD88 Summary Field Tests: 1 Drill Mud: Hammer Weight (lb)-140 Date Bottom Filter Sand Dilatancy: R - Rapid S - Slow N - NoneToughness: L - Low M - Medium H - High Cuttings MiniRAE 2000 10.6 eV HA23-5 Samples S5 Water Concrete Hammer Fall (in.) Bentonite Seal Finish Elevation - of Casing Bottom Winch Automatic Hammer Time Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Sample ID Boring No. J. NitshDrilling Equipment and Procedures 17 May 20231 Truck T. Danaher Casing Casing: PID Make & Model: Hoist/Hammer: -- Depth (ft) to: Sampler Overburden (ft) Rock Cored (ft) of O - Open End Rod T - Thin Wall Tube U - Undisturbed Sample S - Split Spoon Sample 184.0 (est.) †Note: Maximum particle size is determined by direct observation within the limitations of sampler size. Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)0 5 10 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptionsGEOLOGIC INTERPRETATION) S1 14 S1 13 S318 S419 S520 S6 20 S7 24 0.0 2.0 2.0 4.0 5.0 7.0 7.0 9.0 10.0 12.0 15.0 17.0 17.0 19.0 2864 3 334 2333 4445 34 5 6 2 5109 1 112 SP- SM SP SP SP SP SP ML CL 10 5 50 80 75 75 60 60 25 10 20 20 35 35 10 10 5 5 5 5 5 90 100 50.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 191.70.3 190.02.0 187.05.0 176.016.0 -TOPSOIL- Medium dnese brown poorly graded SAND with silt (SP-SM), mps 0.5 in., no structure, no odor, moist Loose red-brown poorly graded SAND (SP), mps 4 mm., no structure, no odor, moist -FILL- Loose yellow brown to brown poorly graded SAND (SP), mps 2 mm, no structure, no odor, moist Similar to S3 -GLACIOFLUVIAL DEPOSITS- Loose brown poorly graded SAND (SP), mps 1 mm, no structure, no odor, moist Similar to S5 Stiff olive-brown to gray-brown sandy SILT (ML) interbedded with silty CLAY (CL), mps 0.1 mm, strong structure, no odor, moist to wet Very soft gray-brown lean CLAY (CL), laminated, no odor, wet -LACUSTRINE DEPOSITS- 15 File No. 31 Location HA23-6 Time (hr.) 6/8/2023 Inside Diameter (in.)None Boring No. Driller Datum Type Barrel Rig Make & Model: Grout Screen Well Diagram Sheet No. 8 June 2023 of Hole 30 1 3/8 -- Elapsed Riser Pipe Start Bit Type:S H&A Rep. Plasticity: N - Nonplastic L - Low M - Medium H - HighDry Strength: N - None L - Low M - Medium H - High V - Very High Drilling 0204385-000 See Plan NAVD88 24 Summary Field Tests: 2 Drill Mud: Hammer Weight (lb)-140300 Date Bottom Filter Sand Dilatancy: R - Rapid S - Slow N - NoneToughness: L - Low M - Medium H - High Cuttings MiniRAE 2000 10.6 eV HA23-6 Samples S7, U2 Water Concrete Hammer Fall (in.) Bentonite Seal Finish Elevation - of Casing Bottom Driven Winch Automatic Hammer Time Water Level Data Note: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Sample ID Boring No. J. NitshDrilling Equipment and Procedures 8 June 20231 Truck T. Danaher Casing Casing: PID Make & Model: Hoist/Hammer: -- Depth (ft) to: Sampler Overburden (ft) Rock Cored (ft) of HW Roller Bit O - Open End Rod T - Thin Wall Tube U - Undisturbed Sample S - Split Spoon Sample 4.0 192.0 (est.) †Note: Maximum particle size is determined by direct observation within the limitations of sampler size. Client Contractor Seaboard Drilling, LLC Project Smith College Lazarus-Wurtele Center, Smith College, Northampton, MA Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)0 5 10 15 20 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptionsGEOLOGIC INTERPRETATION) U1 S824 U2 20.0 22.0 25.0 27.0 29.0 31.0 WOH WOH WOHWOH CL CL CL 100 100 100 0.0 161.031.0 Note: Collected Shelby Tube sample (U1) Similar to S7 -LACUSTRINE DEPOSITS- Note: Collected Shelby Tube sample (U2) BOTTOM OF EXPLORATION 31.0 FT File No. Boring No.HA23-6 Sheet No. HA23-6 2of2 NOTE: Soil identification based on visual-manual methods of the USCS as practiced by Haley & Aldrich, Inc. Boring No. 0204385-000 Sample No.& Rec. (in.)SampleDepth (ft)TEST BORING REPORT H&A-TEST BORING-07-2 REV-W/PID COL-NO FT HA-LIB09-BOS-HAR - COPY.GLB HA-TB+CORE+WELL-07-2 W FENCE.GDT \\HALEYALDRICH.COM\SHARE\CF\PROJECTS\0204385\GINT\0204385-000.GPJ 19 Jun 23Depth (ft)20 25 30 Sampler Blowsper 6 in.USCS SymbolGravel Sand % Fine% Coarse% Medium% Fine% Fines% CoarsePID Readings(ppm)(sample/bkgd)DRAFT StratumChangeElev/Depth (ft)VISUAL-MANUAL IDENTIFICATION AND DESCRIPTION (Density/consistency, color, GROUP NAME, max. particle size†,structure, odor, moisture, optional descriptions GEOLOGIC INTERPRETATION) Northampton MA – Stormwater Report 11/01/2023 | Nitsch #15150 19 APPENDIX H Phosphorus, Nitrogen, and TSS Removal Calculations Phosphorus, Nitrogen, and TSS Removal Calculation (MS4 Methodology) PHOSPHORUS REMOVAL CALCULATIONS Project Name: Smith College Project Location:Northampton MA Project Number:15150 Prepared by: SEK Checked By:CMH Date:10/30/2023 Step 1 - Baseline Phosphorus Loading (Existing Land Cover Loading) Land Use:Commercial/Industrial (Institutional) Area Export Rate P Load ac lbs/acre/yr lbs P/yr Impervious Site Area 0.34 1.78 0.61 Pervious Site Area 0.61 0.37 0.22 Total Site Area 0.95 0.83 Step 2 - Development Phosphorus Loading (Proposed Land Cover Loading) Area Export Rate P Load ac lbs/acre/yr lbs P/yr Impervious Site Area 0.34 1.78 0.61 Pervious Site Area 0.61 0.37 0.22 Total Site Area 0.95 0.83 Step 3 - Required Phosphorus Load Reduction Phosphorus Reduction Requirement (Refer to City/Town Regulations)50% Phosphorus Reduction Required (lbs/year)0.42 Total Phosphorus Reduction through Land Conversion (Ex - Pr Phosphorus Load) lbs/year 0.00 Remaining Reduction Required After Land Conversion (lbs/year)0.42 Step 4 - Structural Stormwater Strategies Surface Type Treated Area (ac) P Load Rate (lbs/ac/yr) Starting P Load (lbs/yr) Phosphorus Removal (%) % of Year Used P Removed (lbs/yr) Permeable Pavers Impervious 0.02 1.78 0.04 100%0.03 Pervious 0.06 0.37 0.02 100%0.02 0.04 Bioretention Basins Impervious 0.07 1.78 0.13 100%0.12 Pervious 0.29 0.37 0.11 100%0.10 0.21 Impervious 0.11 1.78 0.19 100%0.14 Pervious 0.02 0.37 0.01 100%0.01 0.15 Impervious 0.12 1.78 0.22 100% 0.11 Pervious 0.16 0.37 0.06 100% 0.03 0.14 0.55 Silt Prison Existing Proposed 70% 89% Phosphorus Removed through Structural Stormwater Strategies 50% Roof Treatment (thorugh landscape filter structure)76% Calculate baseline phosphorus load per Appendix F, Attachment 1 of the MS4 permit. Export rate determined from Table 1-2 Calculate phosphorus load changes due to development per Appendix F, Attachment 1 of the MS4 Permit. Export rate determined from Table 1-2. Calculate Phosphorus load reduction for structural BMPs in the Watershed per EPA MS4 Permit Appendix F Attachment 3 Step 5 - Operational Strategies Enhanced Sweeping Program Impervious Area to be Swept (ac) P Load Rate (lbs/ac/yr) Sweeping Type P Reduction Factor Annual Frequency P Removed (lbs/yr) 0 1.78 0.00 0.00 0.000 Catch Basin Cleaning Program Impervious Area to Catch Basins (ac) P Load Rate (lbs/ac/yr) P Reduction Factor P Removed (lbs/yr) 0 1.78 0.00 0.000 Organic Waste and Leaf Litter Collection Program Impervious Area (ac) P Load Rate (lbs/ac/yr) P Reduction Factor P Removed (lbs/yr) 0 1.78 0.00 0.000 0.00 Step 6 - Phosphorus Removal Summary Total Phosphorus Reduction Required 0.42 Total Phosphorus Reduction through Land Conversion 0.00 Total Phosphorus Removal Through Structural Stormwater Strategies 0.55 Total Phosphorus Removal Through Operational Strategies 0.00 Total Phosphorus Reduction 0.55 Total Phosphorus Reduction Provided by Project (% Reduction)66% Total Phosphorus Removed through Operational Strategies (lbs/year) Calculate Phosphorus load reduction for operational BMPs in the Watershed per EPA MS4 Permit Appendix F Attachment 2 methodology using Enhanced sweeping nutrient reduction (Table 2-4), Catch Basin Cleaning Nutrient Reduction (Table 2-5) and Enhanced Organic Waste and Leaf Litter. TSS REMOVAL CALCULATIONS Project Name: Smith college Project Number:15150 Prepared by: SEK Checked By:CMH Date:10/30/2023 Step 1 - Baseline TSS Loading (Existing Land Cover Loading) Area Export Rate TSS Load ac lbs/acre/yr lbs P/yr Impervious Site Area 0.34 337.39 115.72 Pervious Site Area 0.61 91 55.15 Total Site Area 0.95 170.87 Step 2 - Development TSS Loading (Proposed Land Cover Loading) Land Use:Commercial/Industrial (institutional) Area Export Rate TSS Load ac lbs/acre/yr lbs P/yr Impervious Site Area 0.34 337.39 115.72 Pervious Site Area 0.61 91 55.15 Total Site Area 0.95 170.87 Step 3 - Required TSS Load Reduction TSS Reduction Requirement (Refer to City/Town Regulations)80% TSS Reduction Required 136.70 Total TSS Removal through Land Conversion (Ex - Pr TSS Load)0.00 Remaining Reduction Required After Land Conversion (lbs/year)136.70 Step 4 - Structural Stormwater Strategies Surface Type Treated Area (ac) TSS Load Rate (lbs/ac/yr) Starting TSS Load (lbs/yr) TSS Removal (%) % of Year Used TSS Removed (lbs/yr) Permeable Pavers Impervious 0.02 337.39 7.42 100%6.98 Pervious 0.06 91 5.37 100%5.05 12.02 Bioretention Basins Impervious 0.07 337.39 24.63 100%24.63 Pervious 0.29 91 26.75 100%26.75 51.38 Landscape Filter for Roof Impervious 0.11 337.39 36.10 100%35.74 (Biofiltration)Pervious 0.02 91 2.09 100%2.07 37.81 Silt Prisons Impervious 0.12 337.39 42.09 100%26.52 Pervious 0.16 91 14.63 100%9.21 35.73 136.95 TSS Removed through Structural Stormwater Strategies Existing Proposed 94% 100% 99% 63% Calculate TSS load changes due to development per Appendix F, Attachment 1 of the MS4 Permit. Export rate determined from the EPA BATT Calculate TSS load changes due to development per Appendix F, Attachment 1 of the MS4 Permit. Export rate determined from the EPA BATT Step 5 - TSS Removal Summary Total TSS Reduction Required 136.70 Total TSS Reduction Through Land Conversion 0.00 Total TSS Removal Through Structural Stormwater Strategies 136.95 Total TSS Reduction 136.95 Total TSS Reduction Provided by Project (% Reduction)80% POLLUTANT REMOVAL CALCULATIONS- POROUS PAVEMENT Project Name: Smith College Project Number:15150 Prepared by: SEK Checked By:CMH Date:10/30/2023 BMP Name:Permeable Pavers Depth of Filter Course (in):18 Provided Phosphorus Removal 70% Provided Nitrogen Removal 77% Provided TSS Removal 94% POLLUTANT REMOVAL CALCULATIONS- BIOFILTRATION Project Name: Smith College Project Number:15150 Prepared by: SEK Checked By:CMH Date:######### BMP Name:Bioretention Basins Impervious Area Tributary to BMP (ac):0.073 Impervious Area Tributary to BMP (sf):3179.88 Outlet Elevation from Infiltration System:varies; see hydroCAD Design Storage Volume of the surface pond (cf)*:240 Surface Area of the Basin (sf):1528 Planting Soil Depth (ft):2 Planting Soil Void Ratio:20% Planting Soil Volume (CF):611.2 Pea Stone Depth (ft) 0.33 Pea Stone Void Ratio 40% Pea Stone Volume (CF) 201.696 Crushed Stone Reservoir Depth 1 Crushed Stone Reservoir Void Ratio 40% Crushed Stone Reservoir Storage Volume (cf)611.2 Total Design Storage Volume (cf)1664.096 Treatment Depth Provided (ft):0.5233204 Treatment Depth Provided (in):6.2798445 Provided Phosphorus Removal 89% Provided Nitrogen Removal 86% Provided TSS Removal 100% *Note that the design storage volume was determined from HydroCAD, the volume of storage provided below the lowest outlet was used POLLUTANT REMOVAL CALCULATIONS- BIOFILTRATION Project Name: Smith College Project Number:15150 Prepared by: SEK Checked By:CMH Date:10/30/2023 BMP Name:Landscape Filter Impervious Area Tributary to BMP (ac):0.1295 Impervious Area Tributary to BMP (sf):5641.02 Outlet Elevation from Infiltration System:Distribution Pipe Design Storage Volume of the surface pond (cf)*:0 Surface Area of the Basin (sf):593 Planting Soil Depth (ft):2 Planting Soil Void Ratio:20% Planting Soil Volume (CF):237.2 Crushed Stone Reservoir Depth 1 Crushed Stone Reservoir Void Ratio 40% Crushed Stone Reservoir Storage Volume (cf) 237.2 Total Design Storage Volume (cf)474.4 Treatment Depth Provided (ft):0.084098266 Treatment Depth Provided (in):1.009179191 Provided Phosphorus Removal 76% Provided Nitrogen Removal 75% Provided TSS Removal 99%