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13-073 Rockridge Drainage Report_Stamped_02-10-15.pdf Stormwater Hydrology Report i Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  TABLE OF CONTENTS   1. NARRATIVE, FIGURES, & CHECKLIST    1.1 Narrative    1.2 Figures   Locus Plan  1 FEMA Flood Insurance Rate Map  2 Priority and Estimated Habitats of Rare Species & Wildlife Map  3 USDA Soils Map    1.3 Stormwater Checklist    1.4 References    2. CONSTRUCTION & LONG‐TERM POLLUTION PREVENTION AND OPERATION & MAINTENANCE PLAN    2.1 Recommended Construction & Long‐Term Stormwater Pollution Prevention Plan and  Operation & Maintenance Plan    2.2 Illicit Discharge Statement    3. HYDROLOGY MODEL USING HYDROCAD    3.1 HydroCAD Pre  3.1.1 Pre‐Drainage Subcatchment Area Plan (PRE)  3.1.2 Pre‐Drainage Routing    3.2 HydroCAD Post  3.2.1 Post‐Drainage Subcatchment Area Plan (POST)  3.2.2 Post‐Drainage Routing    4. STORMWATER MANAGEMENT CALCULATIONS    4.1 Supplemental Stormwater Calculations    4.2 Total Suspended Solids Calculations    4.3 Hydrodynamic Separator Data    5. SOIL DATA    5.1 Record Testing Data, Record Boring Logs, and Building Boring Logs    5.2 NRCS Soil Survey  Section 1 Narrative, Figures, & Checklist   ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   Stormwater Narrative for a Three‐Story Residential Building  Addition at Rockridge Retirement Facility    EXECUTIVE SUMMARY  Deaconess Abundant Life Communities (“Applicant”) proposes to construct a three‐story residential  building addition located in the southeast corner of the developed residential property designated as  Assessor’s Parcel 13‐073‐001 with street addresses of 25 & 37 Coles Meadow Road in Northampton,  Massachusetts. The parcel is owned by New England Deaconess Association and is occupied by one‐ and  three‐story buildings/cottages housing a residential retirement community consisting of 100  independent, assisted living, and memory support residential units.  The project is identified by the  Applicant as “Proposed Addition to Rockridge Retirement Facility.”  The subject property is an 11.524 acre± trapezoidal parcel with the long axis oriented northeast to  southwest. An internal lot line under common ownership separates two properties described by Deed  1539~634 and Deed 1541~127. The parcel’s Coles Meadow Road frontage is located to the southwest  and North King Street (US Route 5 & MA Route 10) frontage is located to the southeast. The property to  the northwest and northeast is owned by the Homeowner’s at Laurel Park Condominium Trust.  An  existing single‐story residential house with attached garage and asphalt driveway occupy the southeast  corner of the property.  Two detached garages and a small utility shed are located northwest of the  house.  A single‐story building abutted on each end by three‐story buildings is located in the center of  the property.  Along the rear (northwest) property line are 12 single‐story cottages.  Several parking  areas, driveways, and sidewalks provide vehicular and pedestrian access through the site.  The  remainder of the site north and east of the buildings is wooded uplands bisected by a bordering  vegetated wetland depression.  The bordering vegetated wetlands adjacent to the project area were  delineation on November 25, 2014 by Northeast Land & Water, LLC.  A record ALTA dated December 1,  2011 provided approximate locations for the remainder of the wetlands on the property.  The entire parcel slopes towards the two discharge points under North King Street (US Route 5 & MA  Route 10) along the east side of the bordering vegetated wetland.  An existing 24” concrete box culvert  drains the southern portion of the property, and existing 30” twin culverts drain the northern portion of  the property.  Because the entire proposed limits of work reside within the southern section of the  property, this report is limited to the areas of development and only focuses on potential stormwater  runoff reaching the 24” concrete box culvert.  The remainder of the developed site is tributary to the  existing stormwater system and underground detention developed in 2003.  The parcel is within zoning district “Suburban Residential (SR).”  According to the April 3, 1978 FEMA  Flood Insurance Rate Map for the City of Northampton, Hampshire County, Community Panel Number  2501670002A, the entire parcel is located within Zone C (no shading), which is defined as “areas of  minimal flooding.”  Erosion control will be provided between the improvements and the wetland resource areas. A long  term pollution prevention plan has been prepared and is contained in Section 2. The site is proposed to  be permitted under “New Development” seeking full compliance with Standards as applicable.  ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com     PROPOSED IMPROVEMENTS  The Applicant proposes to construct a three‐story residential building addition located in the southeast  corner of the developed residential property.  The addition will include 39 memory support and assisted  living elderly house apartments.  This will bring the property total to 139 independent, assisted living,  and memory support residential units.  In additional to the building, 25 proposed parking spaces are  located north and east of the existing buildings.  The existing service entrance driveway off of North King  Street will be upgraded to accommodate the parking stalls.  Wet and dry utility services to the existing  and proposed buildings will be improved as needed.  Existing vegetation bordering the new facility and  parking areas will be minimally cleared.  A majority of the proposed parking stalls will be constructed  with a porous pavement while the driveway will be asphalt pavement.  Pedestrian access will be  achieved through a network of lighted ADA compliant walkways from either the parking areas or the  public right‐of‐way. Impervious areas will increase by approximately 0.42 acres± (18,093 SF±) and have  reduced calculated total property open space from 74.1% to 70.2%.  The attached Post‐Development  Drainage Plan contains the sub‐catchments for each tributary watershed.  The weighted average CN  value for the post‐development watershed has increased from 60 to 69 within the limits of work for this  project.  A closed‐conveyance stormwater management system is proposed to route, detain, and control the  release rates of stormwater generated by the building addition and new parking areas.  High‐density  polyethylene (HDPE) and corrugated metal pipe (CMP) connect between a series of precast manholes,  deep sump hooded catch basins, water quality units, and underground detention basins.  The two  underground detention basin facilities are fabricated from perforated 48” diameter aluminized type 2  CMP to provide the required detention volume.  The underground detention basins are backfilled with  1‐1/2” double washed stone and wrapped with an engineered non‐woven filter fabric to provide  additional storage area and to facilitate infiltration into the surrounding soils.  Clean roof stormwater  runoff will be directed to one of the underground detention basins for groundwater recharge.  The proposed site improvements are shown on the plans provided under separate cover entitled  “Proposed Addition to Rockridge Retirement Facility; 25 & 37 Coles Meadow Road; Northampton, MA”  revised through February 10, 2015 as prepared by ProTerra Design Group, LLC.    OBJECTIVE OF CALCULATIONS & METHODOLOGY  The purpose of this stormwater narrative is to examine the stormwater runoff from the proposed  retirement facility addition and parking lot improvements based upon the applicable performance  standards contained within the Massachusetts Department of Environmental Protection Stormwater  Management Handbook and within the context of the City of Northampton City Code Chapter 281‐ Stormwater Management as well as the Stormwater Management Permit Application.  The goal of the calculations is to mitigate for the three‐story retirement facility addition, paved parking,  and paved access drive. The hydrology calculations attached show that addition of porous pavement  ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   and two separate underground detention systems is sufficient to ensure post‐development peak runoff  rates approximate pre‐development peak flow. Type III 24‐hour SCS design storms for the 1‐year, 2‐year,  10‐year, and 100‐year design storm events were compared for both pre‐development and post‐ development drainage conditions per the requirements of the City of Northampton Stormwater  Management Regulations and Stormwater Management Permit Application.   The HydroCAD Stormwater Modeling System computer program (version 10.00) by Applied  Microcomputer Systems, Inc. is used to develop stormwater runoff rates and volumes for the existing  and proposed conditions at the project site. The HydroCAD software is a hydrograph generation and  routing program similar to TR‐20. The software uses Soil Conservation Service (SCS) Unit Hydrograph  Methodology. This drainage analysis was developed utilizing a Type III 24‐hour storm as developed by  the SCS. Information regarding the equations and calculation procedures utilized in HydroCAD will be  made available upon request. Drainage area maps for both pre‐ and post‐constructed conditions have  been included in this submission.   The design storm frequencies and corresponding rainfall depths were compiled from Technical Paper  No. 40, “Rainfall Frequency Atlas of the United States for Durations from 30 Minutes to 24 Hours and 1  to 100 Years” and have been estimated as follows for Hampshire County, Massachusetts:  Storm Frequency (Years)* Rainfall Depth (Inches)  1  2  2.5  3.0  10 4.5  100 6.4    *Design storm events analyzed per requirements outlined in the  City of Northampton “Stormwater Permit Application”    The groundwater recharge volume was calculated based on impervious areas over hydrologic group A &  B soils.   An adjustment for the minimum groundwater recharge volume was calculated based on the  fact that approximately 19% of the proposed impervious areas will not be directed toward the  infiltration basins.  Each infiltration basin was designed to hold and infiltrate the entire 2‐year design  storm event without releasing through the storm sewer conveyance system.  A long‐term infiltration  rate of 2.41 inches per hour was utilized for loamy sand per 1982 Rawls Rates.    ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   SITE SURFACE WATER HYDROLOGY & SOILS  The site, as previously described, contains multiple residential structures and parking facilities within the  southern half of the property with the last addition constructed in 2003.  Runoff from these existing  developed areas is captured by multiple stormwater catch basins connected to an underground storm  sewer convey system.  Underground water quality structures provide sediment removal for runoff  generated by the existing parking areas.  Eventually, the stormwater runoff is collected in an  underground detention/infiltration basin north of the existing buildings.  An outlet pipe discharges  stormwater from the underground facility near the bordering vegetated wetland area.  The remainder  of the existing property is largely undeveloped, partially wooded, and contains bordering vegetated  wetland resources. Runoff from the undeveloped area is captured within the bordering vegetated  wetland resource before discharging offsite.    Slopes on the parcel range from 1‐33% towards the central bordering vegetated wetland area.   Ultimately, stormwater drains southeasterly towards the Connecticut River approximately 1/3 mile  southeast of the project site.  The Connecticut River is classified as a Category 5 Water shown on the  Mass EPA Integrated List of Water (2012) making it “waters requiring a TMDL.”  According to Mass EPA,  TMDLs are needed for impairments causing Escherichia coli and PCB in fish tissue.  Stormwater from  impervious areas within the project are directed towards water quality inlets (LID treatment) and  underground detention/infiltration basins prior to being released off‐site.  As a result, in our opinion,  the project will not contribute to impairments.  The soils underlying the developed areas of the parcel, including the project area, are classified as  “Hinckley loamy sand” and “Charlton‐rock outcrop‐Hollis complex.” These soils are classified by the  USDA Natural Resources Conservation Service (NRCS) as hydrologic group A & B, respectively.  The record deep observation hole logs dated July 10, 2007 describe the soils as “loamy sand” near the  surface changing to a “medium sand” or “loamy fine sand.” Groundwater near the project area was not  observed within the depths of the record deep observation hole logs.  However, mottling was observed  between the layers of fine sand and loamy fine sand in test pit #3.  This mottling was most liking caused  by a wetting layer or pause and not reflective of a groundwater level.  Based on the previous project’s  soil investigation near the existing underground detention/infiltration system, a silt loam layer or lense  varying in depth may existing near the proposed infiltration BMPs.  If this is encountered during  construction near the porous pavement and underground detention/infiltration basins, it will be  removed.    DESCRIPTION OF STORMWATER MANAGEMENT STANDARDS   The following is an explanation of how the proposed project contributes to proper stormwater  management practices using the applicable provisions of the 2008 Massachusetts Stormwater  Regulations near the project area.   No New Untreated Discharges (Standard 1) ‐ No new stormwater system conveyances will discharge  untreated runoff into the resource or buffer areas or cause erosion in the onsite wetlands. The parking  ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   stalls are constructed of porous pavement and any excessive stormwater runoff will be collected by  deep sump catch basins before routing through water quality inlets.  An underground  detention/infiltration basin with controlled release will overflow to a discharge pipe with level spreader  to reduce the likelihood of erosive flow. Ninety‐four percent TSS removal efficiency is achieved in this  treatment train.  A separate driveway area will just be treated with a proprietary treatment practice  (water quality inlet) designed to remove an average of 60% of the TSS. All disturbed surfaces will be  covered by pavement or seeded and mulched to prevent erosion.  Peak Rate Attenuation (Standard 2) ‐ The peak discharge rates were calculated with the aid of a  hydrograph routing program using TR‐20 methodology. Porous pavement and two underground  detention/infiltration basins with sufficient storage help attenuate the peak flows. A multi‐stage outlet  structure at each underground system has been sized to meet the runoff rates for the 1‐year, 2‐year, 10‐ year, and 100‐year design storm events and reduce the volume of runoff over unmitigated levels.  The  underground systems will partially detain the 100‐year design storm event to provide a buffer against  offsite flooding impacts.  An emergency overflow orifice has been incorporated into the outlet structure  of each underground system to convey the 100‐year design storm event.  Studies have shown that the  average curve number of porous pavements to range from a low of 45 to a high of 89.  A conservative  curve number for was utilized for the porous pavement to reduce runoff rates.  Storage and infiltration  was only assumed within the underground detention facilities.  Calculations show that pre and post  levels are approximately the same or below at the 1‐year, 2‐year, 10‐year, and 100‐year design storm  events.    Recharge (Standard 3) – Increased recharge has been provided by utilizing suitable soils under the  underground detention with exfiltration to mitigate the areas of impervious runoff from the proposed  building addition and parking/driveway areas.  Porous pavement will be installed within the parking  stalls to provide additional infiltration areas; however, these areas were not included in the required  storage recharge volume calculations.  Water Quality (Standard 4) –The proposed stormwater management system has been designed to  provide the required calculated removal of the total suspended solids (TSS) on the proposed site per the  Massachusetts DEP Stormwater Management Policy.  A long‐term pollution prevention plan has been  developed and included with this report.  The combine treatment trains of porous pavement, deep  sump and hooded catch basins, proprietary treatment practices (water quality inlets), and subsurface  infiltration structures has been designed to remove an average of 90% of the TSS from the total site  stormwater runoff.  The underground detention/infiltration systems are estimated to provide for a  water quality volume using the “½ inch rule.”   Land Uses with Higher Pollutant Loads (Standard 5) –The proposed use as a residential retirement  community consisting of independent, assisted living, and memory support residential units is not  considered a land use with high pollutant loads.  Critical Areas (Standard 6) ‐ The project area is located within the Connecticut River Watershed. Runoff  from the proposed facility and the existing developments on the property drain to the wetland area  located within the north half of the property. An existing 24” concrete box culvert drains the wetland  area under North King Street (US Route 5 & MA Route 10), and eventually stormwater travels into the  ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   Interstate 91 drainage system.  Ultimately, stormwater flows into the Connecticut River approximately  1/3 mile southeast of the project site.  The site is not located within an Area of Critical Environmental Concern (ACEC) or within an Outstanding  Resource Water (ORW) based upon MassGIS data resources. The Connecticut River is classified as a  Category 5 Water shown on the Mass EPA Integrated List of Water (2012) making it a water requiring a  TMDL.  The proposed addition to the residential retirement community will not produce any sewage or  untreated runoff that would exacerbate any TMDL. As a result, in our opinion, the project will not  contribute to impairments.  Redevelopment (Standard 7) – The project strives to meet all of the applicable Stormwater Management  Standards.  Construction Period Pollution Prevention Plan and Erosion and Sedimentation Control (Standard 8) – A  combination of staked hay bales, filter‐fabric fencing, and/or mulch socks will be used during  construction as outlined in the Operation & Maintenance Plan of Standard 9 and shown on the  accompanying plan set. Silt‐laden runoff shall be directed towards vegetated areas, temporary  sedimentation basins, and diversion swales. It is not anticipated that dewatering will be required;  however, if required, any dewatering activities will utilize a temporary stilling basin as required to  promote infiltration and include methods for source control. A 5,000 gallon or greater frac tank may be  employed as necessary to help settle additional suspended solids before discharge (as applicable).  Operation and Maintenance Plan (Standard 9) – An Operation and Maintenance (O&M) plan has been  customized to fit the design of the “Proposed Addition to Rockridge Retirement Facility” site. Provisions  to maintain runoff control devices have been assured through structural, non‐structural, and  construction management approaches. Please see the O&M plan appended to this report.  Prohibition of Illicit Discharges (Standard 10) – The Operation and Maintenance plan required by  Standard 9 includes measures to prevent illicit discharges. An Illicit Discharge Compliance Statement is  included in Section 2.     ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   BEST MANAGEMENT PRACTICES (BMPs)  The facility design was able to meet the existing drainage conditions by providing porous pavement  areas, deep sump catch basins, water quality inlets, underground detention basins with exfiltration, and  a level spreader/energy dissipater at the pipe discharge point to increase infiltration and reduce erosion  near the wetlands. A general description of the devices incorporated is indicated below.  1. Porous Pavement  Porous Pavement is proposed within the parking stalls associated with the new parking lot and along the  upgraded access drive north of the existing building.  Porous pavement will allow stormwater to  percolate through the pavement surface and back into the ground.   An underdrain system will collect  excess stormwater and will convey it to the storm sewer system.  Porous pavement is used to promote  volume reduction, provide treatment of the water quality volume, reduce effective imperviousness, and  provide storage volume for the groundwater recharge.  2. Deep Sump Catch Basins  Deep sump catch basins are underground retention systems designed to remove trash, debris, and  coarse sediment from stormwater runoff.  A snout, hood, or elbow connected to the outlet pipe allows  floatables such as oils and greases to remain within the structure while stormwater flows downstream.   A sump area below the outlet pipe provides storage for sediment to settle.  Deep sump catch basin do  not provide volume reduction benefits.    3. Water Quality Inlets  Water quality inlets are proprietary structures which provide settling or separation of sediments and  other pollutants.  The water quality inlet is installed below ground and uses sedimentation, screening,  filtration, or hydrodynamic separation for stormwater quality treatment.  Pipes from surrounding storm  sewer collect systems or an inlet grate on the top of the structure provide stormwater inflow to the  structure with a single outlet pipe of cleaned stormwater.  These devices do not provide volume  reduction benefits.  4. Underground Detention Basins with Exfiltration  Two separate underground detention basins with exfiltration are proposed. Underground detention  basin #1 is located east of the proposed building addition and designed to control the proposed building  roof runoff.  Underground detention basin #2 is located south of the entrance off of North King Street  (US Route 5 & MA Route 10) and designed to control the proposed parking lot areas and access drive  runoff.  Each basin consists of a stone bedding area with perforated CMP pipe and an outlet structure  located within a manhole.  The underground detention basins are sized to hold the 2‐year design storm  event runoff volume and infiltrate it into the ground.  The outlet structure is design to control the  release of larger design storm events to meet existing overall runoff rates.  An emergency overflow  orifice has been incorporated into the outlet structure to convey the 100‐year design storm event.   Discharged water from the basins will flow out an appropriately sized storm sewer system to an outfall  with a level spreader.  ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   5. Level spreaders/Energy Dissipaters  Level spreaders are sharp crested outlets constructed at zero grade across the slope consisting of a  timber to disperse or spread concentrated flow thinly over a receiving area. These BMPs are proposed  to disperse concentrated stormwater runoff before discharging to the wetland resource area. Plunge  pool energy dissipaters are proposed adjacent to the level spreaders near the outlet to calm the outflow  before dispersing over the crest.  ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   SUMMARY OF HYDROLOGIC CALCULATIONS  The results of the pre‐ and post‐construction hydrology calculations provided are summarized in the  following tables. The tables correspond to the design points or study areas as indicated on the drainage  area maps and hydrograph routing calculations. The project aim was to study pre and post runoff for the  proposed work associated with the retirement facility addition and parking lot improvements.   TOTAL RUNOFF PEAK (CFS) FROM THE SITE TO   WETLAND AREA NORTH OF PROJECT DESIGN POINT 1/10    Type III SCS 24‐HR  STORM  EXISTING  (DP#1)  PROPOSED  (DP#10) * DIFFERENCE  1 – YEAR 0.18 0.14 ‐0.04  2 – YEAR 0.41 0.26 ‐0.15  10 – YEAR * 1.74 1.48 ‐0.26  100 – YEAR * 4.19 4.14 ‐0.05  *Infiltration was not allowed in the model for the 10‐year and 100‐year proposed analysis.    TOTAL RUNOFF PEAK (CFS) FROM THE SITE TO   EXISTING PARKING LOT DESIGN POINT 2/20    Type III SCS 24‐HR  STORM  EXISTING  (DP#2)  PROPOSED  (DP#20) DIFFERENCE  1 – YEAR 0.01 0.01 0.00  2 – YEAR 0.03 0.02 ‐0.01  10 – YEAR 0.13 0.11 ‐0.02  100 – YEAR 0.30 0.27 ‐0.03  ProTerra Design Group, LLC Ph:(413)320‐4918 4 Bay Road, Building A, Suite 200 Fax:(413)320‐4917 Hadley, MA 01035 E: info@proterra‐design.com   The peak runoff flow at design point (DP1/10) shows slight decreases indicating no change in the  proposed constructed condition versus the pre‐constructed condition for the 1‐year, 2‐year, 10‐year,  and 100‐year design storm events.  The proposed stormwater conveyance system will not discharge  untreated stormwater runoff into any resource or buffer areas.  Two underground detention with  exfiltration basins will store and infiltrate stormwater into the surrounding soils.  The peak runoff flow at design point (DP2/20) shows the same or slight decreases indicating no change  in the proposed constructed condition versus the pre‐construction condition for the 1‐year, 2‐year, 10‐ year, and 100‐year design storm events.  Stormwater at design point (DP2/20) will enter the existing  stormwater system and be treated before discharging into any resource or buffer areas similar to the  existing conditions.    CONCLUSION  The project has provided sufficient mitigation in peak runoff to offset the impacts of light clearing and  grading by providing sediment capture, increasing infiltrative cover, and reducing erosion through Best  Management Practices (BMPs).  All proposed work including but not limited to the three‐story building  addition, access drive, parking upgrades, and stormwater BMPs are designed to promote infiltration and  incorporate low impact development standards. Storm runoff volumes and flows will be maintained  over existing conditions for the 1‐year, 2‐year, 10‐year, and 100‐year design storm events.  PR. 3-STORY BUILDING ADDITION FIG.1FEMA FLOOD INSURANCE RATE MAP IN T E R S T A T E 9 1 CO L E S M E A D O W R O A D MARIAN STREET EX. BORDERING VEGETATED WETLAND NO R T H K I N G S T R E E T (U S R T . 5 & M A R T . 1 0 ) FIG.2 NHESP BOUNDARY OF PRIORITY HABITATS OF RARE SPECIES PRIORITY AND ESTIMATED HABITATS OF RARE SPECIES & WILDLIFE MAP PR. 3-STORY BUILDING ADDITION IN T E R S T A T E 9 1 CO L E S M E A D O W R O A D MARIAN STREET EX. BORDERING VEGETATED WETLAND NO R T H K I N G S T R E E T (U S R T . 5 & M A R T . 1 0 ) NHESP BOUNDARY OF ESTIMATED HABITATS OF RARE WILDLIFE 14-046 swcheck.doc • 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): Porous Pavement 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. 14-046 swcheck.doc • 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. 14-046 swcheck.doc • 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. 14-046 swcheck.doc • 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. 14-046 swcheck.doc • 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. 14-046 swcheck.doc • 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. Stormwater Hydrology Report ii Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  1.4 REFERENCES    1. Commonwealth of Massachusetts, Department of Environmental Protection, Stormwater  Management Standards Handbook. Volumes 1‐3 February 2008 (DEP Stormwater Management  Policy 2008).    2. Commonwealth of Massachusetts, Department of Environmental Protection.  310 CMR 10.00:   Massachusetts Wetlands Protection Act Regulations. 2008.    3. Commonwealth of Massachusetts, Department of Environmental Protection.  314 CMR 6.00:   Massachusetts Groundwater Quality Standards. 1990.    4. Commonwealth of Massachusetts, Department of Environmental Protection.  314 CMR 4.00:   Massachusetts Surface Water Quality Standards. 2007.    5. Commonwealth of Massachusetts, Department of Environmental Protection.  314 CMR 9.00:   Massachusetts Water Quality Regulations. 2008.    6. United States Department of Agriculture, Natural Resources Conservation Services Urban  Hydrology for Small Watersheds, Technical Release 55 (TR‐55). June 1986.    7. United States Department of Agriculture, Natural Resources Conservation Services Project  Formulation Hydrology Program System, Technical Release 20 (TR‐20). Oct. 2004.    8. Tetra Tech, Inc., United States EPA – Region 1, Stormwater Best Management Practices (BMP)  Performance Analysis. Dec 2008.    9. PVPC, MA DEP, & USEPA – Region 1, Artificial Recharge: Evaluation and Guidance to  Municipalities. Nov 1996.    10. City of Northampton, MA City Code. Chapter 281: Stormwater Management. June 2004.    11. City of Northampton, MA. Stormwater Management Permit Application. 2012.    Section 2 Construction & Long-Term Pollution Prevention and Operation & Maintenance Plan Operation & Maintenance Plan 1 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  RECOMMENDED CONSTRUCTION & LONG‐TERM STORMWATER POLLUTION  PREVENTION PLAN and OPERATION & MAINTENANCE (O&M) PLAN  TO COMPLY WITH STORMWATER STANDARDS 4, 8, 9 & 10  FOR THREE‐STORY RESIDENTIAL BUILDING ADDITION    PROJECT OVERVIEW    Deaconess Abundant Life Communities (“Applicant”) proposes to construct a three‐story residential  building addition located in the southeast corner of the developed residential property. The addition will  include 39 memory support and assisted living elderly house apartments.  This will bring the property  total to 139 independent, assisted living, and memory support residential units.  In additional to the  building, 25 proposed parking spaces are located north and east of the existing buildings.  The existing  service entrance driveway off of North King Street will be upgraded to accommodate the parking stalls.   Wet and dry utility services to the existing and proposed buildings will be improved as needed.  Existing  vegetation bordering the new facility and parking areas will be minimally cleared.  A majority of the  proposed parking stalls will be constructed with a porous pavement while the driveway will be asphalt  pavement.  Pedestrian access will be achieved through a network of lighted ADA compliant walkways  from either the parking areas or the public right‐of‐way.      A series of deep sump catch basins, water quality inlets, and storm sewer pipe will collect and convey  stormwater runoff to two separate underground detention basins with exfiltration.  A majority of the  proposed parking stalls will be constructed with porous pavement to infiltrate and help reduce overall  site runoff.  Runoff from the site will be discharged to the bordering vegetated wetland area north of  the existing service access driveway before flowing under North King Street.  The project will require  disturbance of approximately 74,000 square feet of land.  Impervious areas will increase by  approximately 0.42 acres± (18,093 SF±) and have reduced calculated total property open space from  74.1% to 70.2%.  The proposed site improvements are shown on the plans provided under separate cover entitled  “Proposed Addition to Rockridge Retirement Facility; 25 & 37 Coles Meadow Road; Northampton, MA”  revised through February 10, 2015 as prepared by ProTerra Design Group, LLC.    OWNER AND RESPONSIBLE PARTY    Owner:    Deaconess Abundant Life Communities  80 Deaconess Road  Concord, MA 01742  Responsible Party:    Rockridge Retirement Facility  c/o Deaconess Abundant Life Communities  25 & 37 Coles Meadow Road  Northampton, MA 01060    The Owner/Responsible Party shall provide maintenance of the parking areas, landscaping, and  stormwater system.     Operation & Maintenance Plan 2 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  CONSTRUCTION MANAGEMENT    Contractor: ________________________  Address: __________________________  _________________________________  Phone Number: ____________________    A construction manager with adequate knowledge and experience on projects of similar size and scope  shall be employed to oversee all site work related construction. The contractor shall incorporate  appropriate techniques to control sediment and erosion pollution during construction in accordance  with the Massachusetts Erosion and Sediment Control Guidelines for Urban and Suburban Areas.    Care should be taken when constructing stormwater control structures and dewatering to install  foundations. Light earthmoving equipment shall be used to excavate in the vicinity of the underground  detention basin areas. Use of heavy‐equipment causes excessive compaction of the soils resulting in  reduced infiltration capacity. At no time shall temporary settling basins be constructed in the vicinity of  the proposed porous pavement areas or underground detention basins in order to prevent the soils  from becoming clogged with sediment.    It is not anticipated that dewatering will be required; however, if required, dewatering activities shall be  directed towards a berm and filter sack to promote infiltration into the ground. If silt‐laden sediment is  encountered than a frac tank approximately 5,000 gallons in size or greater can be employed to settle  pumped groundwater before discharge.    CONSTRUCTION PHASING    The phasing of construction for the building addition and parking expansion shall generally follow the  following sequence. Items may be completed concurrently depending on their location.     Construction of temporary construction exit point  o Installation of stabilized construction entrance   Installation of temporary erosion and sediment control measures along the perimeter of the site  (i.e. inlet protection, silt fence, etc.)   Establishment of schedules for good housekeeping BMPs   Clearing and grubbing of vegetation within limits of work   Excavation/Fill building foundation and underground utility trenches   Installation of building foundation   Installation of storm sewer pipes, underground detention, and inlets   Installation of water, sewer, electric, and all other underground utilities   Backfill operations for building foundation and utility trenches   Construction of building addition above ground   Over‐lot grading   Installation of subgrade under porous pavement   Construction of curb, drives, and parking areas   Installation of new asphalt pavement   Final grading  Operation & Maintenance Plan 3 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA   Re‐vegetation in disturbed areas for final stabilization  o Installation of landscaping per landscape plan   Remove temporary BMPs that are no longer required    EROSION & SEDIMENT CONTROL PHASING    The phasing of erosion and sediment control during construction for the building addition and parking  expansion shall generally follow the following sequence.     Pre‐Disturbance/Site Preparation  o Install stabilized construction entrance  o Install perimeter BMPs (i.e. silt fence, inlet protection)  o Prepare stabilized staging area including concrete washout pit  o Limit access to areas that are not to be disturbed   Construction  o Locate stockpiles in work areas upstream of temporary sediment basin  o Leave disturbed area of site in a surface roughened condition when feasible  o Close excavations as soon as possible  o Protect and repair BMPs, as necessary  o Perform street sweeping, as needed   Backfill and Compacting  o Remove temporary BMPs where appropriate  o Remove limited stored materials and equipment from the site   Final Stabilization  o Install seed/mulch or landscaping as shown on the landscape plan  o Remove all non‐biodegradable temporary BMPs when applicable    EROSION CONTROL BEST MANAGEMENT PRACTICES (BMPs)    During construction, silt‐laden runoff or discharge from dewatering operations (if necessary) will be  prevented from exiting the construction area untreated. Siltation barriers consisting of a filter fabric silt  fence, hay bales or silt socks will be erected in advance of construction along the down‐gradient edge of  all disturbed areas and maintained throughout the construction period. The control of dust and erosion  during the construction period will be managed using a number of Best Management Practices (BMPs)  described below and as shown on the Erosion Control sheet (ES‐1) of the Construction Drawings.    Stabilized Construction Entrance    An apron constructed of coarse aggregate over a geotextile fabric shall cover the transition between the  existing driveway and the new driveway. The size and construction of the entrance is shown on the ES‐1  sheet. This entrance shall be inspected daily and maintained throughout construction activities and  optionally removed after completion.          Operation & Maintenance Plan 4 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  Storm Sewer Inlet Protection    Storm sewer inlet protection is a sediment filter or an excavated impounding area around a storm drain  drop inlet or curb inlet. Its purpose is to prevent sediment from entering storm drainage systems prior  to permanent stabilization of the disturbed area. This practice shall be used where the drainage area to  an inlet is disturbed, it is not possible to temporarily divert the storm drain outfall into a trapping device,  and watertight blocking of the inlets is not advisable. It is not to be used in place of sediment trapping  devices    Temporary Sediment Traps (During Construction)    Small depressions that have stormwater runoff directed into them for increase retention time that  promotes settling out of suspended solids. Tributary drainage areas should be under 1 acre. The storage  volumes should be 1,800 cubic feet per acre of tributary area equaling 1,510 cubic feet for the building  and parking lot areas.  Temporary sedimentation areas should not be located near proposed infiltration  areas.    Silt Fence, Reinforced with Haybales as Required (Compost Berms & Socks can be used as alternatives)    Silt fence or silt sock is installed at the down gradient limit of work. It should be trenched into the  ground 6” and staked without drooping. The woven fabric will allow the passage of stormwater while  filtering out suspended solids. Haybales give added filtering and erosion control. Every 100’ two bales or  silt socks shall be placed and staked perpendicular to the fence. Haybales shall be inert straw or salt hay  type.    Dewatering    If dewatering is required, discharges shall be directed through a settling pool or filter bag prior to  discharge. Outflow of silt‐laden runoff shall not be permitted to flow directly into resource areas. In  some instances, a settling tank may need to be employed. Upon completion of site stabilization, the  BMP’s and conveyance systems shall be thoroughly cleaned of silt and sediment and made ready for the  proposed operation. Discharge points shall be set back from the edge of the resource areas and  monitored by qualified personnel to ensure no impacts to resource areas and compliance with  applicable federal and state regulations. Discharges shall be free from visible floating, suspended, and  settleable solids that would impair the functions of the nearby wetlands and downstream rivers.    Concrete Washout Pit    A concrete washout pit/area must be designated to receive wash water from washing of tools and  concrete mixer chutes, liquid concrete waste from dump trucks, mobile batch mixers, or pump trucks.   Concrete washout activities must be conducted in a manner that does not contribute pollutants to  surface waters or stormwater runoff. Concrete washout areas may be lined or unlined excavated pits in  the ground, commercially manufactured prefabricated washout containers, or aboveground holding  areas constructed of berms, sandbags or straw bales with a plastic liner.  Although unlined washout  areas may be used, lined pits may be required to protect groundwater.  Concrete washout areas shall be  located outside of all wetland buffers and proposed infiltration areas.    Operation & Maintenance Plan 5 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  FINAL STABILIZATION    Final stabilization includes those measures taken to control pollutants in stormwater after soil disturbing  activities are complete.  Practices implemented to achieve final stabilization include:   Installation of asphalt and concrete pavement   Installation of landscaping per the landscape plan   Maintenance of appropriate erosion and sediment control BMPs until final stabilization is  achieved   Removal of temporary BMPs once work is completed and final stabilization achieved    ON‐GOING MAINTENANCE CONTRACT    The Responsible Party shall hire appropriate staff, contract with a maintenance company, or designate a  qualified party to complete ongoing maintenance.    LIVING DOCUMENT PROVISIONS    Due to the difficulty of identifying all sources of potential stormwater contamination and maintenance  activities, this document shall be updated as necessary to reflect new procedures, technologies or  requirements. Ultimately, the Responsible Party will have the authority to implement a plan and  frequency of maintenance as required.    MAINTENANCE LOG    The Responsible Party shall develop and maintain a log of inspections, maintenance, repairs, and  disposal (including location of disposal) during the life of the project. Records shall be maintained for at  least three years and be made available to the Massachusetts Department of Environmental Protection  in accordance with the provisions of the Massachusetts Stormwater Handbook. A sample of such a  maintenance log is provided.    GOOD HOUSEKEEPING PRACTICES DURING CONSTRUCTION    The Responsible Party shall maintain good housekeeping practices by maintaining a clean and orderly  facility to prevent potential pollution sources from coming into contact with stormwater and degrading  water quality. This includes establishing protocols to reduce the possibility of mishandling materials or  equipment and training employees in good housekeeping techniques.     Common areas where good housekeeping practices should be followed shall include: material storage  areas, vehicle and equipment maintenance areas, and loading areas. Good housekeeping practices must  include a designated and secure location for garbage. A schedule for regular pickup and disposal of  garbage and waste materials during construction and routine inspections of containers for leaks and  structural integrity shall be developed. After construction, no trash shall be kept on‐site and shall be  removed by service technicians or contractors when they leave.  Portable toilets shall be installed on site  and maintained throughout construction. Excess concrete and cleanout water from redi‐mix vehicles  shall be directed towards small excavations or constructed boxes for cleanup. Catch basins and drainage  conveyance systems shall not be used for this purpose.    Operation & Maintenance Plan 6 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  Dust Control (Seeding and Topsoiling)    Construction traffic must enter and exit the site at the stabilized construction entrance.  The purpose is  to trap dust and mud that would otherwise be carried off‐site by construction traffic.  Large areas of soil  that are denuded of vegetation and have no protection from particles being picked up and carried by  wind should be protected with a temporary cover or kept under control with water or other soil  adhering products to limit wind transported particles existing the site perimeter.  Water trucks or other  dust control agents will be used, as needed, during construction to reduce dust generated on the site  that may cause off‐site damage, health hazards, and traffic safety problems.    Material Storage    Areas designated for temporary materials storage shall be surrounded on the downhill side by an  erosion control barrier. This area shall be inspected daily for erosion and runoff of stored materials. At  the completion of construction, the area shall be stabilized with vegetation or stone product.    Waste Disposal    A secure location shall be designated for waste storage. Regular pickup and disposal of materials shall be  scheduled. Containers shall be inspected daily for leaks and structural integrity. Portable toilets shall be  installed on site and maintained throughout construction.    MINIMIZING EXPOSURE    The Responsible Party shall minimize exposure of potential pollutant sources from coming into contact  with precipitation and being picked up by stormwater and carried into drains and surface waters. All  materials shall be plainly labeled and stored in an appropriate container in an appropriate location. All  activities which can generate sources of contaminants shall be contained.    LONG‐TERM BMPS: MAINTENANCE    Prior to final completion and full occupancy of the development, a representative of the contractor  and/or Engineer at the responsible parties request shall properly instruct the user of the required  maintenance responsibilities to maintain the effectiveness of the drainage system. The Responsible  Party will implement the procedures and frequencies as they see fit under their current plan and inspect  the systems as needed to maintain minimum effectiveness.    Porous Pavement    During the construction phases of the project, the porous pavement shall be inspected and cleaned as  necessary after storm events with 1” of rainfall or greater.  Thereafter, it shall be inspected and cleaned  at least once per year or as needed during the owner’s regular maintenance of the grounds.  The porous  pavement shall be monitored to ensure that the paving surface drains properly after storms.  Cleanings  shall include using power washer to dislodge trapped particles and then vacuum sweep the area.   Winter sanding and salting shall be avoided on the porous pavements.      Operation & Maintenance Plan 7 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  Deep Sump Catch Basins    During the construction phases of the project, the deep sump catch basins shall be inspected monthly to  monitor the sediment accumulation and sediment removed as necessary after storm events with 1” of  rainfall or greater.  Thereafter, the deep sump catch basins shall be inspected every three months or as  needed during the owner’s regular maintenance of the grounds.  Maintenance shall include cleaning the  units during dry weather when half of the sump capacity is filled.  Any obstructions, sediment, and  debris that could potentially cause clogs shall be removed within the stormwater conveyance system.   Inverts, grates, and hoods shall be checked and replaced as necessary to maintain hydraulic  effectiveness.    Water Quality Inlets    Water quality inlets shall be inspected and cleaned in accordance with the manufacturer’s  recommendations, but no less than inspected twice a year following installation.  Thereafter, these  structures shall be inspected no less than once a year.  Cleanings shall include removal of sediment and  other trapped pollutants. Documentation from the manufacturer is attached.      Underground Detention Basins with Exfiltration    The underground detention facilities have been designed with riser structures at grade to aid the  removal of sediment and debris accumulating in the structure.  Once the system goes online, inspections  should occur after each storm event for the first few months to ensure proper stabilization, function,  and to ensure that the outlets remain free of obstructions.  Thereafter, this structure shall be inspected  and cleaned at least twice per year or as needed during the owner’s regular maintenance of the  grounds. Cleanings shall include removal of accumulated sediment, inspection of the detention  structure, and monitoring groundwater and infiltration rates to ensure proper operation of the systems.   Items to note during inspections include differential settlement, cracking, break‐out, clogging of outlets  and vents, and root infestation.  Water levels should be checked and recorded against rainfall amounts  to verify the drainage system is working properly.    Level Spreaders    During the construction phases of the project, the level spreaders shall be inspected monthly and  cleaned as necessary and/or after storms events with 1” of rainfall or greater. Thereafter, these  structures shall be inspected and cleaned at least once per year or as needed during the owner’s regular  maintenance of the grounds. Cleanings shall include removal of vegetation, and removal of excess  debris.    Energy Dissipaters    During the construction phases of the project, the rip rap energy dissipaters shall be inspected monthly  and cleaned as necessary and/or after storms events with 1” of rainfall or greater. Thereafter, these  structures shall be cleaned at least once per year or as needed during the owner’s regular maintenance  of the grounds. Cleanings shall include removal of vegetation, removal of excess sediment accumulation  and inspection of condition of stone.    Operation & Maintenance Plan 8 Proposed Addition to Rockridge Retirement Facility  Deaconess Abundant Life Communities  Northampton, MA  Outlet Structures    During the construction phases of the project, the underground detention basin outlet structures shall  be inspected monthly to monitor the sediment accumulation and sediment removed as necessary after  storm events with 1” of rainfall or greater.  Thereafter, the underground detention basin outlet  structures shall be inspected and cleaned at least twice per year or as needed during the owner’s regular  maintenance of the grounds.  Maintenance shall include cleaning the structures during dry weather  typically at the same time as the underground detention basin.  Any obstructions, sediment, and debris  that could potentially cause clogs shall be removed within the stormwater conveyance system.  Inverts  and orifices shall be checked and replaced as necessary to maintain hydraulic effectiveness.    Street Sweeping and Cleaning    Soils deposited on paved surfaces shall be swept or cleaned as needed to reduce the potential of  sediment transport and tracking.  Sweeping operations consist of scraping large quantities of sediment  from pavement and/or sweeping, via hand or mechanical means to remove as much deposited sediment  as possible.  During construction, all streets within and immediately surrounding the construction site  shall be cleaned of earth material when sediment has been deposited on the roadway and is being  tracked off‐site.  After construction, driveways and parking areas within the site shall be swept with  vacuum assist at least twice per year to remove sediment that potentially could clog infiltration systems  or storm sewers.    ANNUAL MAINTENANCE COST ESTIMATE    BMP Frequency Unit Cost Subtotal  Porous Pavement 1 visit per year $500 $500  Deep Sump Catch Basins 4 visits per year $300 $1200  Water Quality Inlets 1 visit per year $500 $500  U/G Detention Basins with  Exfiltration  2 visits per year $500 $1000  Level Spreaders / Energy  Dissipaters  1 visit per year $250 $250  Vacuum Assist Street  Sweeping  2 visits per year $300 $600    Total:$4050  The annual maintenance cost does not include the owner’s regular maintenance of the grounds that  would consist of mowing, trash pickup, and re‐paving.  St o r m w a t e r B M P I n s p e c t i o n a n d M a i n t e n a n c e L o g Pr o j e c t N a m e : Pr o p o s e d A d d i t i o n t o R o c k r i d g e R e t i r e m e n t F a c i l i t y; 2 5 & 3 7 C o l e s M e a d o w R o a d ; N o r t h a m p t o n , M A SW P P P C o n t a c t : D e a c o n e s s A b u n d a n t L i f e C o m m u n i t i e s C o n t a c t : _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ P h o n e : _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Begin Dat e E n d D a t e Da t e B M P ID # BM P D e s c r i p t i o n I n s p e c t e d by : Ca u s e f o r In s p e c t i o n Ex c e p t i o n s N o t e d C o m m e n t s a n d Ac t i o n s T a k e n LO N G T E R M S T R U C T U R A L B E S T M A N A G E M E N T P R A C T I C E I N S P E C T I O N & M A I N TE N A N C E M A T R I X A F T E R C O N S T R U C T I O N No t e : B M P ' s s h a l l b e v i s u a l l y i n s p e c t e d a n d r e p a i r e d b y a q u a l i f i e d p a r t y i n a c c o r d a n c e w i t h t h e f o l l o w i n g c h a r t . N o t e t h e s e a r e m i n i m u m i n s p e c t i o n c r i t e r i a / f r e q u e n c i e s an d s h o u l d b e a d j u s t e d t h r o u g h o u t t h e p r o j e c t l i f e s p a n a s r e q u i r e d t o m a i n t a i n e f f e c t i v e n e s s . R e f e r t o m a i n t e n a n c e s t a n d a r d s f o r d r a i n a g e f a c i l i t i e s a n d s t r u c t u r a l be s t m a n a g e m e n t p r a c t i c e s i n t h e " R e c o m m e n d e d L o n g - T e r m S t o r m w a t e r P o l l u t i o n P r e v e n t i o n P l a n . " Conventional & LID Best Management Practices Recommended Minimum Inspection & Maintenance Frequency Erosion/Scouring Tree Growth Hazards Differential Settlement/Seepage Structural Damage/Obstructions Trash & Debris Removal of Accumulated Sediment Slope Integrity *Mow Vegetation/Poor Vegetation Coverage Remove/Reset Filter Fabric & Stone As Required Check - Remove & Replace mulch/media/stone Remove/Reset Riprap as Required De e p S u m p C a t c h B a s i n Q u a r t e r l y   Ou t l e t S t r u c t u r e S e m i - A n n u a l        Wa t e r Q u a l i t y I n l e t A n n u a l l y   Po r o u s P a v e m e n t A n n u a l l y      Em e r g e n c y O v e r f l o w S e m i - A n n u a l       Le v e l S p r e a d e r A n n u a l l y       U/ G D e t e n t i o n B a s i n S e m i - A n n u a l        En e r g y D i s s i p a t e r s A n n u a l l y       CDS® Inspection and Maintenance Guide ENGINEERED SOLUTIONS Maintenance The CDS system should be inspected at regular intervals and maintained when necessary to ensure optimum performance. The rate at which the system collects pollutants will depend more heavily on site activities than the size of the unit. For example, unstable soils or heavy winter sanding will cause the grit chamber to fill more quickly but regular sweeping of paved surfaces will slow accumulation. Inspection Inspection is the key to effective maintenance and is easily performed. Pollutant transport and deposition may vary from year to year and regular inspections will help ensure that the system is cleaned out at the appropriate time. At a minimum, inspections should be performed twice per year (e.g. spring and fall) however more frequent inspections may be necessary in climates where winter sanding operations may lead to rapid accumulations, or in equipment washdown areas. Installations should also be inspected more frequently where excessive amounts of trash are expected. The visual inspection should ascertain that the system components are in working order and that there are no blockages or obstructions in the inlet and separation screen. The inspection should also quantify the accumulation of hydrocarbons, trash, and sediment in the system. Measuring pollutant accumulation can be done with a calibrated dipstick, tape measure or other measuring instrument. If absorbent material is used for enhanced removal of hydrocarbons, the level of discoloration of the sorbent material should also be identified during inspection. It is useful and often required as part of an operating permit to keep a record of each inspection. A simple form for doing so is provided. Access to the CDS unit is typically achieved through two manhole access covers. One opening allows for inspection and cleanout of the separation chamber (cylinder and screen) and isolated sump. The other allows for inspection and cleanout of sediment captured and retained outside the screen. For deep units, a single manhole access point would allows both sump cleanout and access outside the screen. The CDS system should be cleaned when the level of sediment has reached 75% of capacity in the isolated sump or when an appreciable level of hydrocarbons and trash has accumulated. If absorbent material is used, it should be replaced when significant discoloration has occurred. Performance will not be impacted until 100% of the sump capacity is exceeded however it is recommended that the system be cleaned prior to that for easier removal of sediment. The level of sediment is easily determined by measuring from finished grade down to the top of the sediment pile. To avoid underestimating the level of sediment in the chamber, the measuring device must be lowered to the top of the sediment pile carefully. Particles at the top of the pile typically offer less resistance to the end of the rod than consolidated particles toward the bottom of the pile. Once this measurement is recorded, it should be compared to the as-built drawing for the unit to determine weather the height of the sediment pile off the bottom of the sump floor exceeds 75% of the total height of isolated sump. Cleaning Cleaning of a CDS systems should be done during dry weather conditions when no flow is entering the system. The use of a vacuum truck is generally the most effective and convenient method of removing pollutants from the system. Simply remove the manhole covers and insert the vacuum hose into the sump. The system should be completely drained down and the sump fully evacuated of sediment. The area outside the screen should also be cleaned out if pollutant build-up exists in this area. In installations where the risk of petroleum spills is small, liquid contaminants may not accumulate as quickly as sediment. However, the system should be cleaned out immediately in the event of an oil or gasoline spill should be cleaned out immediately. Motor oil and other hydrocarbons that accumulate on a more routine basis should be removed when an appreciable layer has been captured. To remove these pollutants, it may be preferable to use absorbent pads since they are usually less expensive to dispose than the oil/water emulsion that may be created by vacuuming the oily layer. Trash and debris can be netted out to separate it from the other pollutants. The screen should be power washed to ensure it is free of trash and debris. Manhole covers should be securely seated following cleaning activities to prevent leakage of runoff into the system from above and also to ensure that proper safety precautions have been followed. Confined space entry procedures need to be followed if physical access is required. Disposal of all material removed from the CDS system should be done in accordance with local regulations. In many jurisdictions, disposal of the sediments may be handled in the same manner as the disposal of sediments removed from catch basins or deep sump manholes. CDS Diameter Distance from Water Surface Sediment Model to Top of Sediment Pile Storage Capacity ft m ft m yd3 m3 CDS2015-4 4 1.2 3.0 0.9 0.9 0.7 CDS2015 5 1.5 3.0 0.9 1.3 1.0 CDS2020 5 1.5 3.5 1.1 1.3 1.0 CDS2025 5 1.5 4.0 1.2 1.3 1.0 CDS3020 6 1.8 4.0 1.2 2.1 1.6 CDS3030 6 1.8 4.6 1.4 2.1 1.6 CDS3035 6 1.8 5.0 1.5 2.1 1.6 CDS4030 8 2.4 4.6 1.4 5.6 4.3 CDS4040 8 2.4 5.7 1.7 5.6 4.3 CDS4045 8 2.4 6.2 1.9 5.6 4.3 CDS5640 10 3.0 6.3 1.9 8.7 6.7 CDS5653 10 3.0 7.7 2.3 8.7 6.7 CDS5668 10 3.0 9.3 2.8 8.7 6.7 CDS5678 10 3.0 10.3 3.1 8.7 6.7 Table 1: CDS Maintenance Indicators and Sediment Storage Capacities 800.925.5240www.ContechES.com Support• Drawings and specifications are available at www.contechstormwater.com. • Site-specific design support is available from our engineers. ©2014 Contech Engineered Solutions LLC Contech Engineered Solutions LLC provides site solutions for the civil engineering industry. Contech’s portfolio includes bridges, drainage, sanitary sewer, stormwater, earth stabilization and wastewater treament products. For information, visit www.ContechES.com or call 800.338.1122 NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS AN EXPRESSED WARRANTY OR AN IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. SEE THE CONTECH STANDARD CONDITION OF SALES (VIEWABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION. The product(s) described may be protected by one or more of the following US patents: 5,322,629; 5,624,576; 5,707,527; 5,759,415; 5,788,848; 5,985,157; 6,027,639; 6,350,374; 6,406,218; 6,641,720; 6,511,595; 6,649,048; 6,991,114; 6,998,038; 7,186,058; 7,296,692; 7,297,266; 7,517,450 related foreign patents or other patents pending. cdsMaintenance 11/14 ENGINEERED SOLUTIONS CDS Inspection & Maintenance Log CDS Model: Location: Water Floatable Describe Maintenance Date depth to Layer Maintenance Personnel Comments sediment1 Thickness2 Performed —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— 1. The water depth to sediment is determined by taking two measurements with a stadia rod: one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than the values listed in table 1 the system should be cleaned out. Note: to avoid underestimating the volume of sediment in the chamber, the measuring device must be carefully lowered to the top of the sediment pile. 2. For optimum performance, the system should be cleaned out when the floating hydrocarbon layer accumulates to an appreciable thickness. In the event of an oil spill, the system should be cleaned immediately. VortSentry® HS Maintenance The VortSentry HS system should be inspected at regular intervals and maintained when necessary to ensure optimum performance. The rate at which the system collects pollutants will depend more heavily on site activities than the size of the unit, i.e., unstable soils or heavy winter sanding will cause the treatment chamber to fi ll more quickly, but regular sweeping will slow accumulation. Inspection Inspection is the key to effective maintenance and is easily performed. Pollutant deposition and transport may vary from year to year and regular inspections will help ensure that the system is cleaned out at the appropriate time. At a minimum, inspections should be performed twice per year (i.e. spring and fall) however more frequent inspections may be necessary in equipment washdown areas and in climates where winter sanding operations may lead to rapid accumulations of a large volume of sediment. It is useful and often required as part of a permit to keep a record of each inspection. A simple inspection and maintenance log form for doing so is available for download at www.contechstormwater.com. The VortSentry HS should be cleaned when the sediment has accumulated to a depth of two feet in the treatment chamber. This determination can be made by taking two measurements with a stadia rod or similar measuring device; one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than the distance given in Table 1, the VortSentry HS should be maintained to ensure effective treatment. Cleaning Cleaning of the VortSentry HS should be done during dry weather conditions when no fl ow is entering the system. Cleanout of the VortSentry HS with a vacuum truck is generally the most effective and convenient method of excavating pollutants from the system. Simply remove the manhole cover and insert the vacuum hose into the sump. All pollutants can be removed from this one access point from the surface with no requirements for Confi ned Space Entry. In installations where the risk of petroleum spills is small, liquid contaminants may not accumulate as quickly as sediment. However, an oil or gasoline spill should be cleaned out immediately. Motor oil and other hydrocarbons that accumulate on a more routine basis should be removed when an appreciable layer has been captured. To remove these pollutants, it may be preferable to use adsorbent pads, which solidify the oils. These are usually much easier to remove from the unit individually, and less expensive to dispose than the oil/water emulsion that may be created by vacuuming the oily layer. Floating trash can be netted out if you wish to separate it from the other pollutants. Manhole covers should be securely seated following cleaning activities to prevent leakage of runoff into the system from above and also to ensure proper safety precautions. If anyone physically enters the unit, Confi ned Space Entry procedures need to be followed. Disposal of all material removed from the VortSentry HS should be done is accordance with local regulations. In many locations, disposal of evacuated sediments may be handled in the same manner as disposal of sediments removed from catch basins or deep sump manholes. Check your local regulations for specifi c requirements on disposal. Table 1: VortSentry HS Maintenance Indicators and Sediment Storage Capacities. Distance VortSentry HS Diameter Between Water Sediment Oil Spill Model Surface and Top Storage Storage of Storage Sump in. m ft. m yd3 m3 gal. liter HS36 36 0.9 3.6 1.1 0.5 0.4 83 314 HS48 48 1.2 4.7 1.4 0.9 0.7 158 598 HS60 60 1.5 6.0 1.8 1.5 1.1 258 978 HS72 72 1.8 7.1 2.2 2.1 1.6 372 1409 HS84 84 2.1 8.4 2.6 2.9 2.2 649 2458 HS96 96 2.4 9.5 2.9 3.7 2.8 845 3199 1. The water depth to sediment is determined by taking two measurements with a stadia rod: one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than the distance given in Table 1, the system should be cleaned out. Note: To avoid underestimating the volume of sediment in the chamber, the measuring device must be carefully lowered to the top of the sediment pile. 2. For optimum performance, the system should be cleaned out when the fl oating hydrocarbon layer accumulates to an appreciable thickness. In the event of an oil spill, the system should be cleaned immediately. VortSentry HS Inspection & Maintenance Log VortSentry HS Model: Location: Water Floatable Describe Maintenance Date depth to Layer Maintenance Personnel Comments shipment1 Thickness2 Performed —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— —————————————————————————————————————————————————————————— Section 3 Hydrology Model Using HydroCAD TA B L E  OF  SU B C A T C H M E N T S  & CO V E R  TY P E (P a r t i a l  Si t e  ‐   Ju s t  Ca t c h m e n t  Ar e a  As s o c i a t e d  wi t h  Pr o p o s e d  Bu i l d i n g  Ad d i t i o n ) Su b ‐ ca c h m e n t So i l Hy d . Gr o u p Ro o f P a v e d G r a s s G r a v e l W o o d e d Po r o u s   Pa v e m e n t To t a l EX ‐1 25 3 A A 5 1 0 5 1 0 EX ‐1 71 1 C B 8 6 5 9 3 1 8 4 8 2 8 2 9 5 3 5 6 EX ‐2 25 3 A A 4 5 2 5 1 5 4 3 3 9 3 0 9 9 9 8 EX ‐2 71 1 C B 4 3 5 1 6 7 4 6 0 5 6 8 1 6 5 EX ‐3 25 3 A A 2 6 9 5 9 9 6 5 1 3 2 1 9 1 7 7 6 0 4 3 6 3 9 EX ‐3 71 1 C B 2 7 8 6 8 2 4 4 0 5 7 1 1 1 5 9 EX ‐4 25 3 A A 1 3 1 1 5 2 1 4 3 3 2 8 0 4 5 0 6 9 EX ‐4 71 1 C B 4 3 8 4 7 9 6 8 2 3 1 1 5 7 1 6 1 6 8 2 1 2 0 4 TO T A L 3 6 5 4 2 3 1 4 2 3 2 1 8 6 2 0 0 4 4 4 1 1 4 0 1 0 5 1 0 0 P‐1 25 3 A A 1 4 1 6 0 7 5 1 0 1 2 5 8 P‐1 71 1 C B 8 6 3 8 6 1 2 2 5 2 8 3 0 4 5 2 7 P‐2 25 3 A A 5 5 7 9 5 1 7 1 2 6 9 2 1 3 4 4 2 P‐2 71 1 C B 4 3 5 2 2 4 5 5 4 8 5 8 1 6 5 P‐3 25 3 A A 7 0 0 6 6 4 1 9 2 7 2 6 2 P‐3 71 1 C B 4 7 9 6 9 6 8 1 1 0 3 6 8 6 7 P‐4 25 3 A A 1 4 5 0 8 5 8 3 1 1 3 9 6 1 0 7 3 1 3 2 1 6 0 P‐4 71 1 C B 1 6 6 9 2 2 1 0 8 8 P‐5 25 3 A A 1 9 1 5 8 0 7 7 1 P‐5 71 1 C B 4 3 8 5 9 2 0 6 2 7 4 3 1 3 8 5 0 7 1 6 2 7 7 P‐6 25 3 A A 0 P‐6 71 1 C B 6 6 8 2 8 5 7 0 0 1 6 5 3 P‐7 25 3 A A 1 0 1 7 2 7 P‐7 71 1 C B 1 9 6 3 1 4 4 1 0 1 1 3 1 1 8 P‐8 25 3 A A 0 P‐8 71 1 C B 4 8 6 6 6 5 5 2 P‐9 25 3 A A 1 3 4 9 1 3 4 9 P‐9 71 1 C B 1 1 7 2 5 7 1 2 2 9 P‐10 25 3 A A 4 3 9 1 1 8 3 1 3 1 7 2 9 3 9 P‐10 71 1 C B 1 0 0 1 9 6 5 3 5 1 2 4 1 6 TO T A L 1 4 2 1 1 3 0 4 3 0 2 9 6 6 8 0 2 7 9 7 6 2 8 1 5 1 0 5 1 0 0 Pr e ‐Co n s t r u c t i o n Po s t ‐Co n s t r u c t i o n Pr o T e r r a  De s i g n  Gr o u p ,  LL C R o c k r i d g e  Re t i r e m e n t  Fa c i l i t y  (1 4 ‐04 6 ) 2 / 9 / 2 0 1 5 EX-1 EX. AREA TRIBUTARY TO PARKING LOT EX-2 EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST EX-3 EX. AREA TRIBUTARY TO N. KING STREET EX-4 EX. AREA TRIBUTARY TO WETLAND DP 1 WETLAND AREA NORTH OF PROJECT DP 2 EX. PARKING LOT Routing Diagram for 14-046_Pre_DRNPrepared by ProTerra Design Group, LLC, Printed 1/29/2015 HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcat Reach Pond Link 14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 2HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CNDescription (subcatchment-numbers) 0.35139>75% Grass cover, Good, HSG A (EX-2, EX-3, EX-4) 0.38861>75% Grass cover, Good, HSG B (EX-1, EX-3, EX-4) 0.01076Gravel roads, HSG A (EX-4) 0.03685Gravel roads, HSG B (EX-4) 0.36398Paved parking, HSG A (EX-2, EX-3, EX-4) 0.16998Paved parking, HSG B (EX-1, EX-2, EX-3, EX-4) 0.06298Roofs, HSG A (EX-3) 0.02298Roofs, HSG B (EX-1, EX-2, EX-4) 0.57432Woods/grass comb., Good, HSG A (EX-1, EX-2, EX-3, EX-4) 0.43958Woods/grass comb., Good, HSG B (EX-1, EX-2, EX-3, EX-4) 2.41360TOTAL AREA 14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 3HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 1.359HSG AEX-1, EX-2, EX-3, EX-4 1.053HSG BEX-1, EX-2, EX-3, EX-4 0.000HSG C 0.000HSG D 0.000Other 2.413TOTAL AREA 14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 4HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.3510.3880.0000.0000.0000.739>75% Grass cover, GoodEX-1, EX-2, EX-3, EX-4 0.0100.0360.0000.0000.0000.046Gravel roadsEX-4 0.3630.1690.0000.0000.0000.531Paved parkingEX-1, EX-2, EX-3, EX-4 0.0620.0220.0000.0000.0000.084RoofsEX-1, EX-2, EX-3, EX-4 0.5740.4390.0000.0000.0001.013Woods/grass comb., GoodEX-1, EX-2, EX-3, EX-4 1.3591.0530.0000.0000.0002.413TOTAL AREA Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 5HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,866 sf 11.58% Impervious Runoff Depth=0.20"Subcatchment EX-1: EX. AREA TRIBUTARY Flow Length=93' Tc=10.2 min CN=61 Runoff=0.01 cfs 0.002 af Runoff Area=18,163 sf 36.52% Impervious Runoff Depth=0.30"Subcatchment EX-2: EX. AREA Flow Length=346' Tc=23.7 min CN=65 Runoff=0.06 cfs 0.010 af Runoff Area=54,798 sf 23.61% Impervious Runoff Depth=0.08"Subcatchment EX-3: EX. AREA Flow Length=306' Tc=11.8 min CN=55 Runoff=0.01 cfs 0.009 af Runoff Area=26,273 sf 24.91% Impervious Runoff Depth=0.39"Subcatchment EX-4: EX. AREA Flow Length=185' Tc=11.5 min CN=68 Runoff=0.16 cfs 0.019 af Inflow=0.18 cfs 0.038 afReach DP 1: WETLAND AREA NORTH OF PROJECT Outflow=0.18 cfs 0.038 af Inflow=0.01 cfs 0.002 afReach DP 2: EX. PARKING LOT Outflow=0.01 cfs 0.002 af Total Runoff Area = 2.413 ac Runoff Volume = 0.041 af Average Runoff Depth = 0.20" 74.50% Pervious = 1.798 ac 25.50% Impervious = 0.615 ac Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 6HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff=0.01 cfs @ 12.40 hrs, Volume=0.002 af, Depth=0.20" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 59398Paved parking, HSG B 1,84861>75% Grass cover, Good, HSG B 2,82958Woods/grass comb., Good, HSG B 5,86661Weighted Average 5,18788.42% Pervious Area 67911.58% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.011 0.011 0.01 0.01 0.009 0.009 0.008 0.008 0.007 0.007 0.006 0.006 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0.000 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=5,866 sf Runoff Volume=0.002 af Runoff Depth=0.20" Flow Length=93' Tc=10.2 min CN=61 0.01 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 7HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING Runoff=0.06 cfs @ 12.51 hrs, Volume=0.010 af, Depth=0.30" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 4,52598Paved parking, HSG A 1,54339>75% Grass cover, Good, HSG A 3,93032Woods/grass comb., Good, HSG A 43598Roofs, HSG B 1,67498Paved parking, HSG B 6,05658Woods/grass comb., Good, HSG B 18,16365Weighted Average 11,52963.48% Pervious Area 6,63436.52% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=18,163 sf Runoff Volume=0.010 af Runoff Depth=0.30" Flow Length=346' Tc=23.7 min CN=65 0.06 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 8HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff=0.01 cfs @ 13.78 hrs, Volume=0.009 af, Depth=0.08" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 2,69598Roofs, HSG A 9,96598Paved parking, HSG A 13,21939>75% Grass cover, Good, HSG A 17,76032Woods/grass comb., Good, HSG A 27898Paved parking, HSG B 6,82461>75% Grass cover, Good, HSG B 4,05758Woods/grass comb., Good, HSG B 54,79855Weighted Average 41,86076.39% Pervious Area 12,93823.61% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.3420.03000.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 0.3500.02203.01 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 5.11920.01580.63 Shallow Concentrated Flow, Over Grass/Woods C-D Woodland Kv= 5.0 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement D-E Paved Kv= 20.3 fps 11.8306Total Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 9HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.016 0.015 0.014 0.013 0.012 0.011 0.01 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=54,798 sf Runoff Volume=0.009 af Runoff Depth=0.08" Flow Length=306' Tc=11.8 min CN=55 0.01 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 10HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff=0.16 cfs @ 12.20 hrs, Volume=0.019 af, Depth=0.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 1,31198Paved parking, HSG A 52139>75% Grass cover, Good, HSG A 43376Gravel roads, HSG A 2,80432Woods/grass comb., Good, HSG A 43898Roofs, HSG B 4,79698Paved parking, HSG B 8,23161>75% Grass cover, Good, HSG B 1,57185Gravel roads, HSG B 6,16858Woods/grass comb., Good, HSG B 26,27368Weighted Average 19,72875.09% Pervious Area 6,54524.91% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 9.9570.01750.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 1.0740.05881.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 0.1250.04504.31 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 0.5290.03500.94 Shallow Concentrated Flow, Over Grass/Woods D-E Woodland Kv= 5.0 fps 11.5185Total Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 11HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=26,273 sf Runoff Volume=0.019 af Runoff Depth=0.39" Flow Length=185' Tc=11.5 min CN=68 0.16 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 12HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Area =2.278 ac,26.32% Impervious, Inflow Depth = 0.20" for 1-Year event Inflow=0.18 cfs @ 12.33 hrs, Volume=0.038 af Outflow=0.18 cfs @ 12.33 hrs, Volume=0.038 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=2.278 ac 0.18 cfs0.18 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 13HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 2: EX. PARKING LOT Inflow Area =0.135 ac,11.58% Impervious, Inflow Depth = 0.20" for 1-Year event Inflow=0.01 cfs @ 12.40 hrs, Volume=0.002 af Outflow=0.01 cfs @ 12.40 hrs, Volume=0.002 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 2: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.011 0.011 0.01 0.01 0.009 0.009 0.008 0.008 0.007 0.007 0.006 0.006 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0.000 0 Inflow Area=0.135 ac 0.01 cfs0.01 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 14HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,866 sf 11.58% Impervious Runoff Depth=0.37"Subcatchment EX-1: EX. AREA TRIBUTARY Flow Length=93' Tc=10.2 min CN=61 Runoff=0.03 cfs 0.004 af Runoff Area=18,163 sf 36.52% Impervious Runoff Depth=0.51"Subcatchment EX-2: EX. AREA Flow Length=346' Tc=23.7 min CN=65 Runoff=0.12 cfs 0.018 af Runoff Area=54,798 sf 23.61% Impervious Runoff Depth=0.19"Subcatchment EX-3: EX. AREA Flow Length=306' Tc=11.8 min CN=55 Runoff=0.08 cfs 0.020 af Runoff Area=26,273 sf 24.91% Impervious Runoff Depth=0.63"Subcatchment EX-4: EX. AREA Flow Length=185' Tc=11.5 min CN=68 Runoff=0.30 cfs 0.031 af Inflow=0.41 cfs 0.070 afReach DP 1: WETLAND AREA NORTH OF PROJECT Outflow=0.41 cfs 0.070 af Inflow=0.03 cfs 0.004 afReach DP 2: EX. PARKING LOT Outflow=0.03 cfs 0.004 af Total Runoff Area = 2.413 ac Runoff Volume = 0.074 af Average Runoff Depth = 0.37" 74.50% Pervious = 1.798 ac 25.50% Impervious = 0.615 ac Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 15HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff=0.03 cfs @ 12.21 hrs, Volume=0.004 af, Depth=0.37" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 59398Paved parking, HSG B 1,84861>75% Grass cover, Good, HSG B 2,82958Woods/grass comb., Good, HSG B 5,86661Weighted Average 5,18788.42% Pervious Area 67911.58% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=5,866 sf Runoff Volume=0.004 af Runoff Depth=0.37" Flow Length=93' Tc=10.2 min CN=61 0.03 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 16HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING Runoff=0.12 cfs @ 12.43 hrs, Volume=0.018 af, Depth=0.51" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 4,52598Paved parking, HSG A 1,54339>75% Grass cover, Good, HSG A 3,93032Woods/grass comb., Good, HSG A 43598Roofs, HSG B 1,67498Paved parking, HSG B 6,05658Woods/grass comb., Good, HSG B 18,16365Weighted Average 11,52963.48% Pervious Area 6,63436.52% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.125 0.12 0.115 0.11 0.105 0.1 0.095 0.09 0.0850.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=18,163 sf Runoff Volume=0.018 af Runoff Depth=0.51" Flow Length=346' Tc=23.7 min CN=65 0.12 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 17HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff=0.08 cfs @ 12.47 hrs, Volume=0.020 af, Depth=0.19" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 2,69598Roofs, HSG A 9,96598Paved parking, HSG A 13,21939>75% Grass cover, Good, HSG A 17,76032Woods/grass comb., Good, HSG A 27898Paved parking, HSG B 6,82461>75% Grass cover, Good, HSG B 4,05758Woods/grass comb., Good, HSG B 54,79855Weighted Average 41,86076.39% Pervious Area 12,93823.61% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.3420.03000.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 0.3500.02203.01 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 5.11920.01580.63 Shallow Concentrated Flow, Over Grass/Woods C-D Woodland Kv= 5.0 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement D-E Paved Kv= 20.3 fps 11.8306Total Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 18HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.09 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=54,798 sf Runoff Volume=0.020 af Runoff Depth=0.19" Flow Length=306' Tc=11.8 min CN=55 0.08 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 19HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff=0.30 cfs @ 12.18 hrs, Volume=0.031 af, Depth=0.63" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 1,31198Paved parking, HSG A 52139>75% Grass cover, Good, HSG A 43376Gravel roads, HSG A 2,80432Woods/grass comb., Good, HSG A 43898Roofs, HSG B 4,79698Paved parking, HSG B 8,23161>75% Grass cover, Good, HSG B 1,57185Gravel roads, HSG B 6,16858Woods/grass comb., Good, HSG B 26,27368Weighted Average 19,72875.09% Pervious Area 6,54524.91% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 9.9570.01750.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 1.0740.05881.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 0.1250.04504.31 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 0.5290.03500.94 Shallow Concentrated Flow, Over Grass/Woods D-E Woodland Kv= 5.0 fps 11.5185Total Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 20HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=26,273 sf Runoff Volume=0.031 af Runoff Depth=0.63" Flow Length=185' Tc=11.5 min CN=68 0.30 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 21HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Area =2.278 ac,26.32% Impervious, Inflow Depth = 0.37" for 2-Year event Inflow=0.41 cfs @ 12.35 hrs, Volume=0.070 af Outflow=0.41 cfs @ 12.35 hrs, Volume=0.070 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=2.278 ac 0.41 cfs0.41 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 22HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 2: EX. PARKING LOT Inflow Area =0.135 ac,11.58% Impervious, Inflow Depth = 0.37" for 2-Year event Inflow=0.03 cfs @ 12.21 hrs, Volume=0.004 af Outflow=0.03 cfs @ 12.21 hrs, Volume=0.004 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 2: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 Inflow Area=0.135 ac 0.03 cfs0.03 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 23HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,866 sf 11.58% Impervious Runoff Depth=1.08"Subcatchment EX-1: EX. AREA TRIBUTARY Flow Length=93' Tc=10.2 min CN=61 Runoff=0.13 cfs 0.012 af Runoff Area=18,163 sf 36.52% Impervious Runoff Depth=1.33"Subcatchment EX-2: EX. AREA Flow Length=346' Tc=23.7 min CN=65 Runoff=0.38 cfs 0.046 af Runoff Area=54,798 sf 23.61% Impervious Runoff Depth=0.74"Subcatchment EX-3: EX. AREA Flow Length=306' Tc=11.8 min CN=55 Runoff=0.64 cfs 0.078 af Runoff Area=26,273 sf 24.91% Impervious Runoff Depth=1.53"Subcatchment EX-4: EX. AREA Flow Length=185' Tc=11.5 min CN=68 Runoff=0.86 cfs 0.077 af Inflow=1.74 cfs 0.201 afReach DP 1: WETLAND AREA NORTH OF PROJECT Outflow=1.74 cfs 0.201 af Inflow=0.13 cfs 0.012 afReach DP 2: EX. PARKING LOT Outflow=0.13 cfs 0.012 af Total Runoff Area = 2.413 ac Runoff Volume = 0.213 af Average Runoff Depth = 1.06" 74.50% Pervious = 1.798 ac 25.50% Impervious = 0.615 ac Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 24HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff=0.13 cfs @ 12.16 hrs, Volume=0.012 af, Depth=1.08" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 59398Paved parking, HSG B 1,84861>75% Grass cover, Good, HSG B 2,82958Woods/grass comb., Good, HSG B 5,86661Weighted Average 5,18788.42% Pervious Area 67911.58% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=5,866 sf Runoff Volume=0.012 af Runoff Depth=1.08" Flow Length=93' Tc=10.2 min CN=61 0.13 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 25HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING Runoff=0.38 cfs @ 12.36 hrs, Volume=0.046 af, Depth=1.33" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 4,52598Paved parking, HSG A 1,54339>75% Grass cover, Good, HSG A 3,93032Woods/grass comb., Good, HSG A 43598Roofs, HSG B 1,67498Paved parking, HSG B 6,05658Woods/grass comb., Good, HSG B 18,16365Weighted Average 11,52963.48% Pervious Area 6,63436.52% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=18,163 sf Runoff Volume=0.046 af Runoff Depth=1.33" Flow Length=346' Tc=23.7 min CN=65 0.38 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 26HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff=0.64 cfs @ 12.21 hrs, Volume=0.078 af, Depth=0.74" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 2,69598Roofs, HSG A 9,96598Paved parking, HSG A 13,21939>75% Grass cover, Good, HSG A 17,76032Woods/grass comb., Good, HSG A 27898Paved parking, HSG B 6,82461>75% Grass cover, Good, HSG B 4,05758Woods/grass comb., Good, HSG B 54,79855Weighted Average 41,86076.39% Pervious Area 12,93823.61% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.3420.03000.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 0.3500.02203.01 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 5.11920.01580.63 Shallow Concentrated Flow, Over Grass/Woods C-D Woodland Kv= 5.0 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement D-E Paved Kv= 20.3 fps 11.8306Total Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 27HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=54,798 sf Runoff Volume=0.078 af Runoff Depth=0.74" Flow Length=306' Tc=11.8 min CN=55 0.64 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 28HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff=0.86 cfs @ 12.17 hrs, Volume=0.077 af, Depth=1.53" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 1,31198Paved parking, HSG A 52139>75% Grass cover, Good, HSG A 43376Gravel roads, HSG A 2,80432Woods/grass comb., Good, HSG A 43898Roofs, HSG B 4,79698Paved parking, HSG B 8,23161>75% Grass cover, Good, HSG B 1,57185Gravel roads, HSG B 6,16858Woods/grass comb., Good, HSG B 26,27368Weighted Average 19,72875.09% Pervious Area 6,54524.91% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 9.9570.01750.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 1.0740.05881.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 0.1250.04504.31 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 0.5290.03500.94 Shallow Concentrated Flow, Over Grass/Woods D-E Woodland Kv= 5.0 fps 11.5185Total Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 29HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=26,273 sf Runoff Volume=0.077 af Runoff Depth=1.53" Flow Length=185' Tc=11.5 min CN=68 0.86 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 30HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Area =2.278 ac,26.32% Impervious, Inflow Depth = 1.06" for 10-Year event Inflow=1.74 cfs @ 12.20 hrs, Volume=0.201 af Outflow=1.74 cfs @ 12.20 hrs, Volume=0.201 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Inflow Area=2.278 ac 1.74 cfs1.74 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 31HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 2: EX. PARKING LOT Inflow Area =0.135 ac,11.58% Impervious, Inflow Depth = 1.08" for 10-Year event Inflow=0.13 cfs @ 12.16 hrs, Volume=0.012 af Outflow=0.13 cfs @ 12.16 hrs, Volume=0.012 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 2: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=0.135 ac 0.13 cfs0.13 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 32HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,866 sf 11.58% Impervious Runoff Depth=2.28"Subcatchment EX-1: EX. AREA TRIBUTARY Flow Length=93' Tc=10.2 min CN=61 Runoff=0.30 cfs 0.026 af Runoff Area=18,163 sf 36.52% Impervious Runoff Depth=2.65"Subcatchment EX-2: EX. AREA Flow Length=346' Tc=23.7 min CN=65 Runoff=0.80 cfs 0.092 af Runoff Area=54,798 sf 23.61% Impervious Runoff Depth=1.75"Subcatchment EX-3: EX. AREA Flow Length=306' Tc=11.8 min CN=55 Runoff=1.93 cfs 0.184 af Runoff Area=26,273 sf 24.91% Impervious Runoff Depth=2.93"Subcatchment EX-4: EX. AREA Flow Length=185' Tc=11.5 min CN=68 Runoff=1.71 cfs 0.147 af Inflow=4.19 cfs 0.423 afReach DP 1: WETLAND AREA NORTH OF PROJECT Outflow=4.19 cfs 0.423 af Inflow=0.30 cfs 0.026 afReach DP 2: EX. PARKING LOT Outflow=0.30 cfs 0.026 af Total Runoff Area = 2.413 ac Runoff Volume = 0.449 af Average Runoff Depth = 2.23" 74.50% Pervious = 1.798 ac 25.50% Impervious = 0.615 ac Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 33HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff=0.30 cfs @ 12.15 hrs, Volume=0.026 af, Depth=2.28" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 59398Paved parking, HSG B 1,84861>75% Grass cover, Good, HSG B 2,82958Woods/grass comb., Good, HSG B 5,86661Weighted Average 5,18788.42% Pervious Area 67911.58% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment EX-1: EX. AREA TRIBUTARY TO PARKING LOT Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=5,866 sf Runoff Volume=0.026 af Runoff Depth=2.28" Flow Length=93' Tc=10.2 min CN=61 0.30 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 34HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING Runoff=0.80 cfs @ 12.35 hrs, Volume=0.092 af, Depth=2.65" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 4,52598Paved parking, HSG A 1,54339>75% Grass cover, Good, HSG A 3,93032Woods/grass comb., Good, HSG A 43598Roofs, HSG B 1,67498Paved parking, HSG B 6,05658Woods/grass comb., Good, HSG B 18,16365Weighted Average 11,52963.48% Pervious Area 6,63436.52% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment EX-2: EX. AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=18,163 sf Runoff Volume=0.092 af Runoff Depth=2.65" Flow Length=346' Tc=23.7 min CN=65 0.80 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 35HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff=1.93 cfs @ 12.18 hrs, Volume=0.184 af, Depth=1.75" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 2,69598Roofs, HSG A 9,96598Paved parking, HSG A 13,21939>75% Grass cover, Good, HSG A 17,76032Woods/grass comb., Good, HSG A 27898Paved parking, HSG B 6,82461>75% Grass cover, Good, HSG B 4,05758Woods/grass comb., Good, HSG B 54,79855Weighted Average 41,86076.39% Pervious Area 12,93823.61% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.3420.03000.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 0.3500.02203.01 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 5.11920.01580.63 Shallow Concentrated Flow, Over Grass/Woods C-D Woodland Kv= 5.0 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement D-E Paved Kv= 20.3 fps 11.8306Total Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 36HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-3: EX. AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=54,798 sf Runoff Volume=0.184 af Runoff Depth=1.75" Flow Length=306' Tc=11.8 min CN=55 1.93 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 37HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff=1.71 cfs @ 12.16 hrs, Volume=0.147 af, Depth=2.93" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 1,31198Paved parking, HSG A 52139>75% Grass cover, Good, HSG A 43376Gravel roads, HSG A 2,80432Woods/grass comb., Good, HSG A 43898Roofs, HSG B 4,79698Paved parking, HSG B 8,23161>75% Grass cover, Good, HSG B 1,57185Gravel roads, HSG B 6,16858Woods/grass comb., Good, HSG B 26,27368Weighted Average 19,72875.09% Pervious Area 6,54524.91% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 9.9570.01750.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 1.0740.05881.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 0.1250.04504.31 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 0.5290.03500.94 Shallow Concentrated Flow, Over Grass/Woods D-E Woodland Kv= 5.0 fps 11.5185Total Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 38HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment EX-4: EX. AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=26,273 sf Runoff Volume=0.147 af Runoff Depth=2.93" Flow Length=185' Tc=11.5 min CN=68 1.71 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 39HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Area =2.278 ac,26.32% Impervious, Inflow Depth = 2.23" for 100-Year event Inflow=4.19 cfs @ 12.18 hrs, Volume=0.423 af Outflow=4.19 cfs @ 12.18 hrs, Volume=0.423 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 1: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Inflow Area=2.278 ac 4.19 cfs4.19 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Pre_DRN Printed 1/29/2015Prepared by ProTerra Design Group, LLC Page 40HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP 2: EX. PARKING LOT Inflow Area =0.135 ac,11.58% Impervious, Inflow Depth = 2.28" for 100-Year event Inflow=0.30 cfs @ 12.15 hrs, Volume=0.026 af Outflow=0.30 cfs @ 12.15 hrs, Volume=0.026 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Reach DP 2: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 3029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=0.135 ac 0.30 cfs0.30 cfs P-1 AREA TRIBUTARY TO EX. PARKING LOT P-10 AREA TRIBUTARY TO WETLAND P-2 AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING STP-3 BLDG ADDITION & COURTYARD P-4 AREA TRIBUTARY TO N. KING STREET P-5 CB #1P-6 CB #3 P-7 CB #2 P-8 INLET OF CONTECH CDS #2 P-9 CONTECH VORTSENTRY DP-10 WETLAND AREA NORTH OF PROJECT DP-20 EX. PARKING LOT 1P U/G DETENTION ROOF 2P U/G DETENTION PARKING & DRIVEWAY CDSCB CONTECH CDS MH-1CB STORM MH #1 MH-2CB MH #2 Routing Diagram for 14-046_Post_DRNPrepared by ProTerra Design Group, LLC, Printed 2/9/2015 HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcat Reach Pond Link 14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 2HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CNDescription (subcatchment-numbers) 0.42639>75% Grass cover, Good, HSG A (P-1, P-10, P-2, P-3, P-4) 0.25561>75% Grass cover, Good, HSG B (P-1, P-10, P-3, P-5, P-6, P-7, P-8, P-9) 0.37598Paved parking, HSG A (P-1, P-10, P-2, P-3, P-4, P-5, P-7, P-9) 0.32398Paved parking, HSG B (P-1, P-10, P-2, P-3, P-4, P-5, P-6, P-7, P-8, P-9) 0.01470Porous Pavement, HSG A (P-5, P-7) 0.05175Porous Pavement, HSG B (P-5, P-6, P-7) 0.19498Roofs, HSG A (P-3, P-4) 0.13298Roofs, HSG B (P-1, P-2, P-3, P-5) 0.35032Woods/grass comb., Good, HSG A (P-1, P-10, P-2, P-4) 0.29258Woods/grass comb., Good, HSG B (P-1, P-10, P-2, P-4, P-5) 2.41369TOTAL AREA 14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 3HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 1.359HSG AP-1, P-10, P-2, P-3, P-4, P-5, P-7, P-9 1.054HSG BP-1, P-10, P-2, P-3, P-4, P-5, P-6, P-7, P-8, P-9 0.000HSG C 0.000HSG D 0.000Other 2.413TOTAL AREA 14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 4HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.4260.2550.0000.0000.0000.681>75% Grass cover, GoodP-1, P-10, P-2, P-3, P-4, P-5, P-6, P-7, P-8, P-9 0.3750.3230.0000.0000.0000.699Paved parkingP-1, P-10, P-2, P-3, P-4, P-5, P-6, P-7, P-8, P-9 0.0140.0510.0000.0000.0000.065Porous PavementP-5, P-6, P-7 0.1940.1320.0000.0000.0000.326RoofsP-1, P-2, P-3, P-4, P-5 0.3500.2920.0000.0000.0000.642Woods/grass comb., GoodP-1, P-10, P-2, P-4, P-5 1.3591.0540.0000.0000.0002.413TOTAL AREA Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 5HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-42.00 hrs, dt=0.01 hrs, 4201 points x 3 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,785 sf 10.60% Impervious Runoff Depth=0.15"Subcatchment P-1: AREA TRIBUTARY TO Flow Length=93' Tc=10.2 min CN=59 Runoff=0.01 cfs 0.002 af Runoff Area=5,355 sf 10.07% Impervious Runoff Depth=0.05"Subcatchment P-10: AREA TRIBUTARY TO Tc=6.0 min CN=53 Runoff=0.00 cfs 0.001 af Runoff Area=21,607 sf 38.22% Impervious Runoff Depth=0.33"Subcatchment P-2: AREA TRIBUTARY TO Flow Length=346' Tc=23.7 min CN=66 Runoff=0.08 cfs 0.013 af Runoff Area=14,129 sf 90.83% Impervious Runoff Depth=1.87"Subcatchment P-3: BLDG ADDITION & Tc=6.0 min CN=94 Runoff=0.69 cfs 0.051 af Runoff Area=33,248 sf 30.68% Impervious Runoff Depth=0.08"Subcatchment P-4: AREA TRIBUTARY TO Flow Length=223' Tc=10.0 min CN=55 Runoff=0.01 cfs 0.005 af Runoff Area=17,048 sf 38.42% Impervious Runoff Depth=0.65"Subcatchment P-5: CB #1 Tc=6.0 min CN=75 Runoff=0.27 cfs 0.021 af Runoff Area=1,653 sf 40.41% Impervious Runoff Depth=1.00"Subcatchment P-6: CB #3 Tc=6.0 min CN=82 Runoff=0.04 cfs 0.003 af Runoff Area=3,145 sf 62.73% Impervious Runoff Depth=1.45"Subcatchment P-7: CB #2 Tc=6.0 min CN=89 Runoff=0.12 cfs 0.009 af Runoff Area=552 sf 88.04% Impervious Runoff Depth=1.87"Subcatchment P-8: INLET OF CONTECH CDS Tc=6.0 min CN=94 Runoff=0.03 cfs 0.002 af Runoff Area=2,578 sf 97.79% Impervious Runoff Depth=2.16"Subcatchment P-9: CONTECH Tc=6.0 min CN=97 Runoff=0.14 cfs 0.011 af Inflow=0.14 cfs 0.030 afReach DP-10: WETLAND AREA NORTH OF PROJECT Outflow=0.14 cfs 0.030 af Inflow=0.01 cfs 0.002 afReach DP-20: EX. PARKING LOT Outflow=0.01 cfs 0.002 af Peak Elev=193.27' Storage=830 cf Inflow=0.69 cfs 0.051 afPond 1P: U/G DETENTION ROOF Discarded=0.07 cfs 0.051 af Primary=0.00 cfs 0.000 af Outflow=0.07 cfs 0.051 af Peak Elev=191.96' Storage=513 cf Inflow=0.46 cfs 0.035 afPond 2P: U/G DETENTION PARKING & Discarded=0.05 cfs 0.035 af Primary=0.00 cfs 0.000 af Outflow=0.05 cfs 0.035 af Peak Elev=193.28' Inflow=0.46 cfs 0.035 afPond CDS: CONTECH CDS 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' Outflow=0.46 cfs 0.035 af Peak Elev=191.01' Inflow=0.14 cfs 0.011 afPond MH-1: STORM MH #1 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' Outflow=0.14 cfs 0.011 af Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 6HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Peak Elev=191.20' Inflow=0.00 cfs 0.000 afPond MH-2: MH #2 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' Outflow=0.00 cfs 0.000 af Total Runoff Area = 2.413 ac Runoff Volume = 0.117 af Average Runoff Depth = 0.58" 57.53% Pervious = 1.388 ac 42.47% Impervious = 1.025 ac Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 7HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff=0.01 cfs @ 12.45 hrs, Volume=0.002 af, Depth=0.15" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 14198Paved parking, HSG A 60739>75% Grass cover, Good, HSG A 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 38698Paved parking, HSG B 1,22561>75% Grass cover, Good, HSG B 2,83058Woods/grass comb., Good, HSG B 5,78559Weighted Average 5,17289.40% Pervious Area 61310.60% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.007 0.007 0.006 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0.000 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=5,785 sf Runoff Volume=0.002 af Runoff Depth=0.15" Flow Length=93' Tc=10.2 min CN=59 0.01 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 8HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff=0.00 cfs @ 14.82 hrs, Volume=0.001 af, Depth=0.05" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 43998Paved parking, HSG A 1,18339>75% Grass cover, Good, HSG A 1,31732Woods/grass comb., Good, HSG A 10098Paved parking, HSG B 1,96561>75% Grass cover, Good, HSG B 35158Woods/grass comb., Good, HSG B 5,35553Weighted Average 4,81689.93% Pervious Area 53910.07% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 0 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=5,355 sf Runoff Volume=0.001 af Runoff Depth=0.05" Tc=6.0 min CN=53 0.00 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 9HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff=0.08 cfs @ 12.48 hrs, Volume=0.013 af, Depth=0.33" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 5,57998Paved parking, HSG A 5,17139>75% Grass cover, Good, HSG A 2,69232Woods/grass comb., Good, HSG A 43598Roofs, HSG B 2,24598Paved parking, HSG B 5,48558Woods/grass comb., Good, HSG B 21,60766Weighted Average 13,34861.78% Pervious Area 8,25938.22% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=21,607 sf Runoff Volume=0.013 af Runoff Depth=0.33" Flow Length=346' Tc=23.7 min CN=66 0.08 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 10HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff=0.69 cfs @ 12.09 hrs, Volume=0.051 af, Depth=1.87" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 7,00698Roofs, HSG A 6498Paved parking, HSG A 19239>75% Grass cover, Good, HSG A 4,79698Roofs, HSG B 96898Paved parking, HSG B 1,10361>75% Grass cover, Good, HSG B 14,12994Weighted Average 1,2959.17% Pervious Area 12,83490.83% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=14,129 sf Runoff Volume=0.051 af Runoff Depth=1.87" Tc=6.0 min CN=94 0.69 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 11HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff=0.01 cfs @ 13.77 hrs, Volume=0.005 af, Depth=0.08" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 1,45098Roofs, HSG A 8,58398Paved parking, HSG A 11,39639>75% Grass cover, Good, HSG A 10,73132Woods/grass comb., Good, HSG A 16698Paved parking, HSG B 92258Woods/grass comb., Good, HSG B 33,24855Weighted Average 23,04969.32% Pervious Area 10,19930.68% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 8.8560.02300.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 1.11450.01802.16 Shallow Concentrated Flow, Over Grass/Woods B-C Unpaved Kv= 16.1 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 10.0223Total Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 12HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.009 0.009 0.008 0.008 0.007 0.007 0.006 0.006 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0.000 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=33,248 sf Runoff Volume=0.005 af Runoff Depth=0.08" Flow Length=223' Tc=10.0 min CN=55 0.01 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 13HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-5: CB #1 Runoff=0.27 cfs @ 12.10 hrs, Volume=0.021 af, Depth=0.65" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 19198Paved parking, HSG A *58070Porous Pavement, HSG A 43898Roofs, HSG B 5,92098Paved parking, HSG B 6,27461>75% Grass cover, Good, HSG B 3,13858Woods/grass comb., Good, HSG B *50775Porous Pavement, HSG B 17,04875Weighted Average 10,49961.58% Pervious Area 6,54938.42% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-5: CB #1 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=17,048 sf Runoff Volume=0.021 af Runoff Depth=0.65" Tc=6.0 min CN=75 0.27 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 14HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-6: CB #3 Runoff=0.04 cfs @ 12.09 hrs, Volume=0.003 af, Depth=1.00" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 66898Paved parking, HSG B 28561>75% Grass cover, Good, HSG B *70075Porous Pavement, HSG B 1,65382Weighted Average 98559.59% Pervious Area 66840.41% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-6: CB #3 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.048 0.046 0.044 0.042 0.04 0.038 0.036 0.034 0.032 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=1,653 sf Runoff Volume=0.003 af Runoff Depth=1.00" Tc=6.0 min CN=82 0.04 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 15HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-7: CB #2 Runoff=0.12 cfs @ 12.09 hrs, Volume=0.009 af, Depth=1.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 1098Paved parking, HSG A *1770Porous Pavement, HSG A 1,96398Paved parking, HSG B 14461>75% Grass cover, Good, HSG B *1,01175Porous Pavement, HSG B 3,14589Weighted Average 1,17237.27% Pervious Area 1,97362.73% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-7: CB #2 Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Flo w ( c f s ) 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=3,145 sf Runoff Volume=0.009 af Runoff Depth=1.45" Tc=6.0 min CN=89 0.12 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 16HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff=0.03 cfs @ 12.09 hrs, Volume=0.002 af, Depth=1.87" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 48698Paved parking, HSG B 6661>75% Grass cover, Good, HSG B 55294Weighted Average 6611.96% Pervious Area 48688.04% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=552 sf Runoff Volume=0.002 af Runoff Depth=1.87" Tc=6.0 min CN=94 0.03 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 17HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-9: CONTECH VORTSENTRY Runoff=0.14 cfs @ 12.08 hrs, Volume=0.011 af, Depth=2.16" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.50" Area (sf)CNDescription 1,34998Paved parking, HSG A 1,17298Paved parking, HSG B 5761>75% Grass cover, Good, HSG B 2,57897Weighted Average 572.21% Pervious Area 2,52197.79% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-9: CONTECH VORTSENTRY Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 1-Year Rainfall=2.50" Runoff Area=2,578 sf Runoff Volume=0.011 af Runoff Depth=2.16" Tc=6.0 min CN=97 0.14 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 18HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Area =2.280 ac,44.33% Impervious, Inflow Depth = 0.16" for 1-Year event Inflow=0.14 cfs @ 12.09 hrs, Volume=0.030 af Outflow=0.14 cfs @ 12.09 hrs, Volume=0.030 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=2.280 ac 0.14 cfs0.14 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 19HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-20: EX. PARKING LOT Inflow Area =0.133 ac,10.60% Impervious, Inflow Depth = 0.15" for 1-Year event Inflow=0.01 cfs @ 12.45 hrs, Volume=0.002 af Outflow=0.01 cfs @ 12.45 hrs, Volume=0.002 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-20: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 424038363432302826242220181614121086420 Fl o w ( c f s ) 0.007 0.007 0.006 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0.000 0 Inflow Area=0.133 ac 0.01 cfs0.01 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 20HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 1P: U/G DETENTION ROOF Inflow Area =0.324 ac,90.83% Impervious, Inflow Depth = 1.87" for 1-Year event Inflow=0.69 cfs @ 12.09 hrs, Volume=0.051 af Outflow=0.07 cfs @ 12.94 hrs, Volume=0.051 af, Atten= 91%, Lag= 51.5 min Discarded=0.07 cfs @ 12.94 hrs, Volume=0.051 af Primary=0.00 cfs @ 0.00 hrs, Volume=0.000 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 193.27' @ 12.94 hrs Surf.Area= 940 sf Storage= 830 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 102.3 min ( 897.8 - 795.5 ) VolumeInvertAvail.StorageStorage Description #1A191.50'1,382 cf 20.00'W x 47.00'L x 5.50'H Field A 5,170 cf Overall - 1,716 cf Embedded = 3,454 cf x 40.0% Voids #2A192.50'1,716 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3192.50'214 cf 48.0" Round Pipe Storage -Impervious L= 17.0' 3,311 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary192.50'18.0" Round Culvert L= 128.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.50' / 191.30' S= 0.0094 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2Device 1193.68'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1195.31'3.5" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded191.50'2.410 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.07 cfs @ 12.94 hrs HW=193.27' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.07 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=191.50' TW=191.20' (Dynamic Tailwater) 1=Culvert ( Controls 0.00 cfs) 2=Orifice/Grate (10-YR Storm Outlet) ( Controls 0.00 cfs) 3=Orifice/Grate (100-YR Storm Outlet) ( Controls 0.00 cfs) Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 21HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +15.00' Row Adjustment +4.00' Header x 2 = 43.00' Row Length +24.0" End Stone x 2 = 47.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +15.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,716.2 cf Chamber Storage 5,170.0 cf Field - 1,716.2 cf Chambers = 3,453.8 cf Stone x 40.0% Voids = 1,381.5 cf Stone Storage Chamber Storage + Stone Storage = 3,097.7 cf = 0.071 af Overall Storage Efficiency = 59.9% 3 Chambers 191.5 cy Field 127.9 cy Stone Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 22HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.324 ac Peak Elev=193.27' Storage=830 cf 0.69 cfs 0.07 cfs0.07 cfs 0.00 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 23HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 0.82" for 1-Year event Inflow=0.46 cfs @ 12.10 hrs, Volume=0.035 af Outflow=0.05 cfs @ 13.05 hrs, Volume=0.035 af, Atten= 88%, Lag= 57.5 min Discarded=0.05 cfs @ 13.05 hrs, Volume=0.035 af Primary=0.00 cfs @ 0.00 hrs, Volume=0.000 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.96' @ 13.05 hrs Surf.Area= 780 sf Storage= 513 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 86.7 min ( 941.7 - 855.0 ) VolumeInvertAvail.StorageStorage Description #1A190.50'1,150 cf 20.00'W x 39.00'L x 5.50'H Field A 4,290 cf Overall - 1,416 cf Embedded = 2,874 cf x 40.0% Voids #2A191.50'1,416 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3191.50'88 cf 48.0" Round Pipe Storage -Impervious L= 7.0' 2,653 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary191.50'18.0" Round Culvert L= 17.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.50' / 191.30' S= 0.0118 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf #2Device 1192.75'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1194.33'5.7" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded190.50'2.410 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.05 cfs @ 13.05 hrs HW=191.96' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.05 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=190.50' TW=191.20' (Dynamic Tailwater) 1=Culvert ( Controls 0.00 cfs) 2=Orifice/Grate (10-YR Storm Outlet) ( Controls 0.00 cfs) 3=Orifice/Grate (100-YR Storm Outlet) ( Controls 0.00 cfs) Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 24HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +7.00' Row Adjustment +4.00' Header x 2 = 35.00' Row Length +24.0" End Stone x 2 = 39.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +7.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,415.5 cf Chamber Storage 4,290.0 cf Field - 1,415.5 cf Chambers = 2,874.5 cf Stone x 40.0% Voids = 1,149.8 cf Stone Storage Chamber Storage + Stone Storage = 2,565.3 cf = 0.059 af Overall Storage Efficiency = 59.8% 3 Chambers 158.9 cy Field 106.5 cy Stone Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 25HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.514 ac Peak Elev=191.96' Storage=513 cf 0.46 cfs 0.05 cfs0.05 cfs 0.00 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 26HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond CDS: CONTECH CDS Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 0.82" for 1-Year event Inflow=0.46 cfs @ 12.10 hrs, Volume=0.035 af Outflow=0.46 cfs @ 12.10 hrs, Volume=0.035 af, Atten= 0%, Lag= 0.0 min Primary=0.46 cfs @ 12.10 hrs, Volume=0.035 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 193.28' @ 12.10 hrs DeviceRouting InvertOutlet Devices #1Primary192.94'12.0" Round Culvert L= 9.5' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.94' / 192.75' S= 0.0200 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=0.46 cfs @ 12.10 hrs HW=193.28' TW=191.08' (Dynamic Tailwater) 1=Culvert (Barrel Controls 0.46 cfs @ 2.91 fps) Pond CDS: CONTECH CDS InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.514 ac Peak Elev=193.28' 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' 0.46 cfs0.46 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 27HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-1: STORM MH #1 Inflow Area =0.898 ac,64.01% Impervious, Inflow Depth = 0.14" for 1-Year event Inflow=0.14 cfs @ 12.08 hrs, Volume=0.011 af Outflow=0.14 cfs @ 12.08 hrs, Volume=0.011 af, Atten= 0%, Lag= 0.0 min Primary=0.14 cfs @ 12.08 hrs, Volume=0.011 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.01' @ 12.08 hrs DeviceRouting InvertOutlet Devices #1Primary190.84'18.0" Round Culvert L= 105.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 190.84' / 190.00' S= 0.0080 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=0.14 cfs @ 12.08 hrs HW=191.01' TW=0.00' (Dynamic Tailwater) 1=Culvert (Barrel Controls 0.14 cfs @ 1.89 fps) Pond MH-1: STORM MH #1 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=0.898 ac Peak Elev=191.01' 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' 0.14 cfs0.14 cfs Type III 24-hr 1-Year Rainfall=2.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 28HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-2: MH #2 Inflow Area =0.839 ac,61.63% Impervious, Inflow Depth = 0.00" for 1-Year event Inflow=0.00 cfs @ 0.00 hrs, Volume=0.000 af Outflow=0.00 cfs @ 0.00 hrs, Volume=0.000 af, Atten= 0%, Lag= 0.0 min Primary=0.00 cfs @ 0.00 hrs, Volume=0.000 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.20' @ 0.00 hrs DeviceRouting InvertOutlet Devices #1Primary191.20'18.0" Round Culvert L= 33.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.20' / 190.94' S= 0.0079 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=191.20' TW=190.84' (Dynamic Tailwater) 1=Culvert ( Controls 0.00 cfs) Pond MH-2: MH #2 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Inflow Area=0.839 ac Peak Elev=191.20' 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' 0.00 cfs0.00 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 29HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-42.00 hrs, dt=0.01 hrs, 4201 points x 3 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,785 sf 10.60% Impervious Runoff Depth=0.30"Subcatchment P-1: AREA TRIBUTARY TO Flow Length=93' Tc=10.2 min CN=59 Runoff=0.02 cfs 0.003 af Runoff Area=5,355 sf 10.07% Impervious Runoff Depth=0.15"Subcatchment P-10: AREA TRIBUTARY TO Tc=6.0 min CN=53 Runoff=0.00 cfs 0.002 af Runoff Area=21,607 sf 38.22% Impervious Runoff Depth=0.54"Subcatchment P-2: AREA TRIBUTARY TO Flow Length=346' Tc=23.7 min CN=66 Runoff=0.15 cfs 0.023 af Runoff Area=14,129 sf 90.83% Impervious Runoff Depth=2.35"Subcatchment P-3: BLDG ADDITION & Tc=6.0 min CN=94 Runoff=0.86 cfs 0.064 af Runoff Area=33,248 sf 30.68% Impervious Runoff Depth=0.19"Subcatchment P-4: AREA TRIBUTARY TO Flow Length=223' Tc=10.0 min CN=55 Runoff=0.05 cfs 0.012 af Runoff Area=17,048 sf 38.42% Impervious Runoff Depth=0.96"Subcatchment P-5: CB #1 Tc=6.0 min CN=75 Runoff=0.42 cfs 0.031 af Runoff Area=1,653 sf 40.41% Impervious Runoff Depth=1.38"Subcatchment P-6: CB #3 Tc=6.0 min CN=82 Runoff=0.06 cfs 0.004 af Runoff Area=3,145 sf 62.73% Impervious Runoff Depth=1.90"Subcatchment P-7: CB #2 Tc=6.0 min CN=89 Runoff=0.16 cfs 0.011 af Runoff Area=552 sf 88.04% Impervious Runoff Depth=2.35"Subcatchment P-8: INLET OF CONTECH CDS Tc=6.0 min CN=94 Runoff=0.03 cfs 0.002 af Runoff Area=2,578 sf 97.79% Impervious Runoff Depth=2.66"Subcatchment P-9: CONTECH Tc=6.0 min CN=97 Runoff=0.17 cfs 0.013 af Inflow=0.26 cfs 0.050 afReach DP-10: WETLAND AREA NORTH OF PROJECT Outflow=0.26 cfs 0.050 af Inflow=0.02 cfs 0.003 afReach DP-20: EX. PARKING LOT Outflow=0.02 cfs 0.003 af Peak Elev=193.67' Storage=1,120 cf Inflow=0.86 cfs 0.064 afPond 1P: U/G DETENTION ROOF Discarded=0.07 cfs 0.064 af Primary=0.00 cfs 0.000 af Outflow=0.07 cfs 0.064 af Peak Elev=192.59' Storage=858 cf Inflow=0.67 cfs 0.050 afPond 2P: U/G DETENTION PARKING & Discarded=0.06 cfs 0.050 af Primary=0.00 cfs 0.000 af Outflow=0.06 cfs 0.050 af Peak Elev=193.36' Inflow=0.67 cfs 0.050 afPond CDS: CONTECH CDS 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' Outflow=0.67 cfs 0.050 af Peak Elev=191.03' Inflow=0.17 cfs 0.013 afPond MH-1: STORM MH #1 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' Outflow=0.17 cfs 0.013 af Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 30HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Peak Elev=191.20' Inflow=0.00 cfs 0.000 afPond MH-2: MH #2 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' Outflow=0.00 cfs 0.000 af Total Runoff Area = 2.413 ac Runoff Volume = 0.166 af Average Runoff Depth = 0.83" 57.53% Pervious = 1.388 ac 42.47% Impervious = 1.025 ac Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 31HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff=0.02 cfs @ 12.34 hrs, Volume=0.003 af, Depth=0.30" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 14198Paved parking, HSG A 60739>75% Grass cover, Good, HSG A 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 38698Paved parking, HSG B 1,22561>75% Grass cover, Good, HSG B 2,83058Woods/grass comb., Good, HSG B 5,78559Weighted Average 5,17289.40% Pervious Area 61310.60% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.021 0.02 0.019 0.018 0.017 0.016 0.015 0.014 0.013 0.012 0.011 0.01 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=5,785 sf Runoff Volume=0.003 af Runoff Depth=0.30" Flow Length=93' Tc=10.2 min CN=59 0.02 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 32HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff=0.00 cfs @ 12.43 hrs, Volume=0.002 af, Depth=0.15" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 43998Paved parking, HSG A 1,18339>75% Grass cover, Good, HSG A 1,31732Woods/grass comb., Good, HSG A 10098Paved parking, HSG B 1,96561>75% Grass cover, Good, HSG B 35158Woods/grass comb., Good, HSG B 5,35553Weighted Average 4,81689.93% Pervious Area 53910.07% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=5,355 sf Runoff Volume=0.002 af Runoff Depth=0.15" Tc=6.0 min CN=53 0.00 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 33HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff=0.15 cfs @ 12.41 hrs, Volume=0.023 af, Depth=0.54" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 5,57998Paved parking, HSG A 5,17139>75% Grass cover, Good, HSG A 2,69232Woods/grass comb., Good, HSG A 43598Roofs, HSG B 2,24598Paved parking, HSG B 5,48558Woods/grass comb., Good, HSG B 21,60766Weighted Average 13,34861.78% Pervious Area 8,25938.22% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=21,607 sf Runoff Volume=0.023 af Runoff Depth=0.54" Flow Length=346' Tc=23.7 min CN=66 0.15 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 34HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff=0.86 cfs @ 12.08 hrs, Volume=0.064 af, Depth=2.35" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 7,00698Roofs, HSG A 6498Paved parking, HSG A 19239>75% Grass cover, Good, HSG A 4,79698Roofs, HSG B 96898Paved parking, HSG B 1,10361>75% Grass cover, Good, HSG B 14,12994Weighted Average 1,2959.17% Pervious Area 12,83490.83% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=14,129 sf Runoff Volume=0.064 af Runoff Depth=2.35" Tc=6.0 min CN=94 0.86 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 35HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff=0.05 cfs @ 12.43 hrs, Volume=0.012 af, Depth=0.19" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 1,45098Roofs, HSG A 8,58398Paved parking, HSG A 11,39639>75% Grass cover, Good, HSG A 10,73132Woods/grass comb., Good, HSG A 16698Paved parking, HSG B 92258Woods/grass comb., Good, HSG B 33,24855Weighted Average 23,04969.32% Pervious Area 10,19930.68% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 8.8560.02300.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 1.11450.01802.16 Shallow Concentrated Flow, Over Grass/Woods B-C Unpaved Kv= 16.1 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 10.0223Total Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 36HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=33,248 sf Runoff Volume=0.012 af Runoff Depth=0.19" Flow Length=223' Tc=10.0 min CN=55 0.05 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 37HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-5: CB #1 Runoff=0.42 cfs @ 12.10 hrs, Volume=0.031 af, Depth=0.96" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 19198Paved parking, HSG A *58070Porous Pavement, HSG A 43898Roofs, HSG B 5,92098Paved parking, HSG B 6,27461>75% Grass cover, Good, HSG B 3,13858Woods/grass comb., Good, HSG B *50775Porous Pavement, HSG B 17,04875Weighted Average 10,49961.58% Pervious Area 6,54938.42% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-5: CB #1 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.46 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=17,048 sf Runoff Volume=0.031 af Runoff Depth=0.96" Tc=6.0 min CN=75 0.42 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 38HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-6: CB #3 Runoff=0.06 cfs @ 12.09 hrs, Volume=0.004 af, Depth=1.38" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 66898Paved parking, HSG B 28561>75% Grass cover, Good, HSG B *70075Porous Pavement, HSG B 1,65382Weighted Average 98559.59% Pervious Area 66840.41% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-6: CB #3 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=1,653 sf Runoff Volume=0.004 af Runoff Depth=1.38" Tc=6.0 min CN=82 0.06 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 39HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-7: CB #2 Runoff=0.16 cfs @ 12.09 hrs, Volume=0.011 af, Depth=1.90" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 1098Paved parking, HSG A *1770Porous Pavement, HSG A 1,96398Paved parking, HSG B 14461>75% Grass cover, Good, HSG B *1,01175Porous Pavement, HSG B 3,14589Weighted Average 1,17237.27% Pervious Area 1,97362.73% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-7: CB #2 Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Flo w ( c f s ) 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=3,145 sf Runoff Volume=0.011 af Runoff Depth=1.90" Tc=6.0 min CN=89 0.16 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 40HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff=0.03 cfs @ 12.08 hrs, Volume=0.002 af, Depth=2.35" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 48698Paved parking, HSG B 6661>75% Grass cover, Good, HSG B 55294Weighted Average 6611.96% Pervious Area 48688.04% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.036 0.034 0.032 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=552 sf Runoff Volume=0.002 af Runoff Depth=2.35" Tc=6.0 min CN=94 0.03 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 41HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-9: CONTECH VORTSENTRY Runoff=0.17 cfs @ 12.08 hrs, Volume=0.013 af, Depth=2.66" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.00" Area (sf)CNDescription 1,34998Paved parking, HSG A 1,17298Paved parking, HSG B 5761>75% Grass cover, Good, HSG B 2,57897Weighted Average 572.21% Pervious Area 2,52197.79% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-9: CONTECH VORTSENTRY Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 2-Year Rainfall=3.00" Runoff Area=2,578 sf Runoff Volume=0.013 af Runoff Depth=2.66" Tc=6.0 min CN=97 0.17 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 42HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Area =2.280 ac,44.33% Impervious, Inflow Depth = 0.26" for 2-Year event Inflow=0.26 cfs @ 12.38 hrs, Volume=0.050 af Outflow=0.26 cfs @ 12.38 hrs, Volume=0.050 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=2.280 ac 0.26 cfs0.26 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 43HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-20: EX. PARKING LOT Inflow Area =0.133 ac,10.60% Impervious, Inflow Depth = 0.30" for 2-Year event Inflow=0.02 cfs @ 12.34 hrs, Volume=0.003 af Outflow=0.02 cfs @ 12.34 hrs, Volume=0.003 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-20: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 424038363432302826242220181614121086420 Fl o w ( c f s ) 0.021 0.02 0.019 0.018 0.017 0.016 0.015 0.014 0.013 0.012 0.011 0.01 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 0 Inflow Area=0.133 ac 0.02 cfs0.02 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 44HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 1P: U/G DETENTION ROOF Inflow Area =0.324 ac,90.83% Impervious, Inflow Depth = 2.35" for 2-Year event Inflow=0.86 cfs @ 12.08 hrs, Volume=0.064 af Outflow=0.07 cfs @ 13.10 hrs, Volume=0.064 af, Atten= 92%, Lag= 60.7 min Discarded=0.07 cfs @ 13.10 hrs, Volume=0.064 af Primary=0.00 cfs @ 0.00 hrs, Volume=0.000 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 193.67' @ 13.10 hrs Surf.Area= 940 sf Storage= 1,120 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 138.9 min ( 928.2 - 789.3 ) VolumeInvertAvail.StorageStorage Description #1A191.50'1,382 cf 20.00'W x 47.00'L x 5.50'H Field A 5,170 cf Overall - 1,716 cf Embedded = 3,454 cf x 40.0% Voids #2A192.50'1,716 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3192.50'214 cf 48.0" Round Pipe Storage -Impervious L= 17.0' 3,311 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary192.50'18.0" Round Culvert L= 128.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.50' / 191.30' S= 0.0094 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2Device 1193.68'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1195.31'3.5" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded191.50'2.410 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.07 cfs @ 13.10 hrs HW=193.67' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.07 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=191.50' TW=191.20' (Dynamic Tailwater) 1=Culvert ( Controls 0.00 cfs) 2=Orifice/Grate (10-YR Storm Outlet) ( Controls 0.00 cfs) 3=Orifice/Grate (100-YR Storm Outlet) ( Controls 0.00 cfs) Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 45HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +15.00' Row Adjustment +4.00' Header x 2 = 43.00' Row Length +24.0" End Stone x 2 = 47.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +15.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,716.2 cf Chamber Storage 5,170.0 cf Field - 1,716.2 cf Chambers = 3,453.8 cf Stone x 40.0% Voids = 1,381.5 cf Stone Storage Chamber Storage + Stone Storage = 3,097.7 cf = 0.071 af Overall Storage Efficiency = 59.9% 3 Chambers 191.5 cy Field 127.9 cy Stone Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 46HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.324 ac Peak Elev=193.67' Storage=1,120 cf 0.86 cfs 0.07 cfs0.07 cfs 0.00 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 47HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 1.16" for 2-Year event Inflow=0.67 cfs @ 12.09 hrs, Volume=0.050 af Outflow=0.06 cfs @ 13.68 hrs, Volume=0.050 af, Atten= 91%, Lag= 95.1 min Discarded=0.06 cfs @ 13.68 hrs, Volume=0.050 af Primary=0.00 cfs @ 0.00 hrs, Volume=0.000 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 192.59' @ 13.68 hrs Surf.Area= 780 sf Storage= 858 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 148.9 min ( 994.7 - 845.8 ) VolumeInvertAvail.StorageStorage Description #1A190.50'1,150 cf 20.00'W x 39.00'L x 5.50'H Field A 4,290 cf Overall - 1,416 cf Embedded = 2,874 cf x 40.0% Voids #2A191.50'1,416 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3191.50'88 cf 48.0" Round Pipe Storage -Impervious L= 7.0' 2,653 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary191.50'18.0" Round Culvert L= 17.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.50' / 191.30' S= 0.0118 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf #2Device 1192.75'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1194.33'5.7" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded190.50'2.410 in/hr Exfiltration over Wetted area Discarded OutFlow Max=0.06 cfs @ 13.68 hrs HW=192.59' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.06 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=190.50' TW=191.20' (Dynamic Tailwater) 1=Culvert ( Controls 0.00 cfs) 2=Orifice/Grate (10-YR Storm Outlet) ( Controls 0.00 cfs) 3=Orifice/Grate (100-YR Storm Outlet) ( Controls 0.00 cfs) Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 48HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +7.00' Row Adjustment +4.00' Header x 2 = 35.00' Row Length +24.0" End Stone x 2 = 39.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +7.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,415.5 cf Chamber Storage 4,290.0 cf Field - 1,415.5 cf Chambers = 2,874.5 cf Stone x 40.0% Voids = 1,149.8 cf Stone Storage Chamber Storage + Stone Storage = 2,565.3 cf = 0.059 af Overall Storage Efficiency = 59.8% 3 Chambers 158.9 cy Field 106.5 cy Stone Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 49HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.514 ac Peak Elev=192.59' Storage=858 cf 0.67 cfs 0.06 cfs0.06 cfs 0.00 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 50HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond CDS: CONTECH CDS Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 1.16" for 2-Year event Inflow=0.67 cfs @ 12.09 hrs, Volume=0.050 af Outflow=0.67 cfs @ 12.09 hrs, Volume=0.050 af, Atten= 0%, Lag= 0.0 min Primary=0.67 cfs @ 12.09 hrs, Volume=0.050 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 193.36' @ 12.09 hrs DeviceRouting InvertOutlet Devices #1Primary192.94'12.0" Round Culvert L= 9.5' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.94' / 192.75' S= 0.0200 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=0.67 cfs @ 12.09 hrs HW=193.36' TW=191.50' (Dynamic Tailwater) 1=Culvert (Barrel Controls 0.67 cfs @ 3.12 fps) Pond CDS: CONTECH CDS InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.514 ac Peak Elev=193.36' 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' 0.67 cfs0.67 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 51HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-1: STORM MH #1 Inflow Area =0.898 ac,64.01% Impervious, Inflow Depth = 0.18" for 2-Year event Inflow=0.17 cfs @ 12.08 hrs, Volume=0.013 af Outflow=0.17 cfs @ 12.08 hrs, Volume=0.013 af, Atten= 0%, Lag= 0.0 min Primary=0.17 cfs @ 12.08 hrs, Volume=0.013 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.03' @ 12.08 hrs DeviceRouting InvertOutlet Devices #1Primary190.84'18.0" Round Culvert L= 105.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 190.84' / 190.00' S= 0.0080 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=0.17 cfs @ 12.08 hrs HW=191.03' TW=0.00' (Dynamic Tailwater) 1=Culvert (Barrel Controls 0.17 cfs @ 2.00 fps) Pond MH-1: STORM MH #1 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=0.898 ac Peak Elev=191.03' 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' 0.17 cfs0.17 cfs Type III 24-hr 2-Year Rainfall=3.00"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 52HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-2: MH #2 Inflow Area =0.839 ac,61.63% Impervious, Inflow Depth = 0.00" for 2-Year event Inflow=0.00 cfs @ 0.00 hrs, Volume=0.000 af Outflow=0.00 cfs @ 0.00 hrs, Volume=0.000 af, Atten= 0%, Lag= 0.0 min Primary=0.00 cfs @ 0.00 hrs, Volume=0.000 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.20' @ 0.00 hrs DeviceRouting InvertOutlet Devices #1Primary191.20'18.0" Round Culvert L= 33.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.20' / 190.94' S= 0.0079 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=191.20' TW=190.84' (Dynamic Tailwater) 1=Culvert ( Controls 0.00 cfs) Pond MH-2: MH #2 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Inflow Area=0.839 ac Peak Elev=191.20' 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' 0.00 cfs0.00 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 53HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-42.00 hrs, dt=0.01 hrs, 4201 points x 3 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,785 sf 10.60% Impervious Runoff Depth=0.96"Subcatchment P-1: AREA TRIBUTARY TO Flow Length=93' Tc=10.2 min CN=59 Runoff=0.11 cfs 0.011 af Runoff Area=5,355 sf 10.07% Impervious Runoff Depth=0.64"Subcatchment P-10: AREA TRIBUTARY TO Tc=6.0 min CN=53 Runoff=0.06 cfs 0.007 af Runoff Area=21,607 sf 38.22% Impervious Runoff Depth=1.40"Subcatchment P-2: AREA TRIBUTARY TO Flow Length=346' Tc=23.7 min CN=66 Runoff=0.48 cfs 0.058 af Runoff Area=14,129 sf 90.83% Impervious Runoff Depth=3.82"Subcatchment P-3: BLDG ADDITION & Tc=6.0 min CN=94 Runoff=1.36 cfs 0.103 af Runoff Area=33,248 sf 30.68% Impervious Runoff Depth=0.74"Subcatchment P-4: AREA TRIBUTARY TO Flow Length=223' Tc=10.0 min CN=55 Runoff=0.41 cfs 0.047 af Runoff Area=17,048 sf 38.42% Impervious Runoff Depth=2.05"Subcatchment P-5: CB #1 Tc=6.0 min CN=75 Runoff=0.93 cfs 0.067 af Runoff Area=1,653 sf 40.41% Impervious Runoff Depth=2.64"Subcatchment P-6: CB #3 Tc=6.0 min CN=82 Runoff=0.12 cfs 0.008 af Runoff Area=3,145 sf 62.73% Impervious Runoff Depth=3.30"Subcatchment P-7: CB #2 Tc=6.0 min CN=89 Runoff=0.27 cfs 0.020 af Runoff Area=552 sf 88.04% Impervious Runoff Depth=3.82"Subcatchment P-8: INLET OF CONTECH CDS Tc=6.0 min CN=94 Runoff=0.05 cfs 0.004 af Runoff Area=2,578 sf 97.79% Impervious Runoff Depth=4.15"Subcatchment P-9: CONTECH Tc=6.0 min CN=97 Runoff=0.26 cfs 0.020 af Inflow=1.48 cfs 0.286 afReach DP-10: WETLAND AREA NORTH OF PROJECT Outflow=1.48 cfs 0.286 af Inflow=0.11 cfs 0.011 afReach DP-20: EX. PARKING LOT Outflow=0.11 cfs 0.011 af Peak Elev=195.30' Storage=2,362 cf Inflow=1.36 cfs 0.103 afPond 1P: U/G DETENTION ROOF Discarded=0.00 cfs 0.000 af Primary=0.29 cfs 0.077 af Outflow=0.29 cfs 0.077 af Peak Elev=194.33' Storage=1,904 cf Inflow=1.38 cfs 0.099 afPond 2P: U/G DETENTION PARKING & Discarded=0.00 cfs 0.000 af Primary=0.28 cfs 0.077 af Outflow=0.28 cfs 0.077 af Peak Elev=194.33' Inflow=1.38 cfs 0.099 afPond CDS: CONTECH CDS 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' Outflow=1.38 cfs 0.099 af Peak Elev=191.21' Inflow=0.64 cfs 0.175 afPond MH-1: STORM MH #1 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' Outflow=0.64 cfs 0.175 af Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 54HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Peak Elev=191.56' Inflow=0.57 cfs 0.154 afPond MH-2: MH #2 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' Outflow=0.57 cfs 0.154 af Total Runoff Area = 2.413 ac Runoff Volume = 0.345 af Average Runoff Depth = 1.71" 57.53% Pervious = 1.388 ac 42.47% Impervious = 1.025 ac Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 55HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff=0.11 cfs @ 12.16 hrs, Volume=0.011 af, Depth=0.96" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 14198Paved parking, HSG A 60739>75% Grass cover, Good, HSG A 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 38698Paved parking, HSG B 1,22561>75% Grass cover, Good, HSG B 2,83058Woods/grass comb., Good, HSG B 5,78559Weighted Average 5,17289.40% Pervious Area 61310.60% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.115 0.11 0.105 0.1 0.095 0.09 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=5,785 sf Runoff Volume=0.011 af Runoff Depth=0.96" Flow Length=93' Tc=10.2 min CN=59 0.11 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 56HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff=0.06 cfs @ 12.12 hrs, Volume=0.007 af, Depth=0.64" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 43998Paved parking, HSG A 1,18339>75% Grass cover, Good, HSG A 1,31732Woods/grass comb., Good, HSG A 10098Paved parking, HSG B 1,96561>75% Grass cover, Good, HSG B 35158Woods/grass comb., Good, HSG B 5,35553Weighted Average 4,81689.93% Pervious Area 53910.07% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=5,355 sf Runoff Volume=0.007 af Runoff Depth=0.64" Tc=6.0 min CN=53 0.06 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 57HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff=0.48 cfs @ 12.35 hrs, Volume=0.058 af, Depth=1.40" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 5,57998Paved parking, HSG A 5,17139>75% Grass cover, Good, HSG A 2,69232Woods/grass comb., Good, HSG A 43598Roofs, HSG B 2,24598Paved parking, HSG B 5,48558Woods/grass comb., Good, HSG B 21,60766Weighted Average 13,34861.78% Pervious Area 8,25938.22% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=21,607 sf Runoff Volume=0.058 af Runoff Depth=1.40" Flow Length=346' Tc=23.7 min CN=66 0.48 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 58HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff=1.36 cfs @ 12.08 hrs, Volume=0.103 af, Depth=3.82" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 7,00698Roofs, HSG A 6498Paved parking, HSG A 19239>75% Grass cover, Good, HSG A 4,79698Roofs, HSG B 96898Paved parking, HSG B 1,10361>75% Grass cover, Good, HSG B 14,12994Weighted Average 1,2959.17% Pervious Area 12,83490.83% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=14,129 sf Runoff Volume=0.103 af Runoff Depth=3.82" Tc=6.0 min CN=94 1.36 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 59HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff=0.41 cfs @ 12.17 hrs, Volume=0.047 af, Depth=0.74" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 1,45098Roofs, HSG A 8,58398Paved parking, HSG A 11,39639>75% Grass cover, Good, HSG A 10,73132Woods/grass comb., Good, HSG A 16698Paved parking, HSG B 92258Woods/grass comb., Good, HSG B 33,24855Weighted Average 23,04969.32% Pervious Area 10,19930.68% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 8.8560.02300.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 1.11450.01802.16 Shallow Concentrated Flow, Over Grass/Woods B-C Unpaved Kv= 16.1 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 10.0223Total Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 60HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.46 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=33,248 sf Runoff Volume=0.047 af Runoff Depth=0.74" Flow Length=223' Tc=10.0 min CN=55 0.41 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 61HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-5: CB #1 Runoff=0.93 cfs @ 12.09 hrs, Volume=0.067 af, Depth=2.05" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 19198Paved parking, HSG A *58070Porous Pavement, HSG A 43898Roofs, HSG B 5,92098Paved parking, HSG B 6,27461>75% Grass cover, Good, HSG B 3,13858Woods/grass comb., Good, HSG B *50775Porous Pavement, HSG B 17,04875Weighted Average 10,49961.58% Pervious Area 6,54938.42% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-5: CB #1 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=17,048 sf Runoff Volume=0.067 af Runoff Depth=2.05" Tc=6.0 min CN=75 0.93 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 62HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-6: CB #3 Runoff=0.12 cfs @ 12.09 hrs, Volume=0.008 af, Depth=2.64" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 66898Paved parking, HSG B 28561>75% Grass cover, Good, HSG B *70075Porous Pavement, HSG B 1,65382Weighted Average 98559.59% Pervious Area 66840.41% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-6: CB #3 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.13 0.125 0.12 0.115 0.11 0.105 0.1 0.095 0.09 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=1,653 sf Runoff Volume=0.008 af Runoff Depth=2.64" Tc=6.0 min CN=82 0.12 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 63HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-7: CB #2 Runoff=0.27 cfs @ 12.09 hrs, Volume=0.020 af, Depth=3.30" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 1098Paved parking, HSG A *1770Porous Pavement, HSG A 1,96398Paved parking, HSG B 14461>75% Grass cover, Good, HSG B *1,01175Porous Pavement, HSG B 3,14589Weighted Average 1,17237.27% Pervious Area 1,97362.73% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-7: CB #2 Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Flo w ( c f s ) 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=3,145 sf Runoff Volume=0.020 af Runoff Depth=3.30" Tc=6.0 min CN=89 0.27 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 64HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff=0.05 cfs @ 12.08 hrs, Volume=0.004 af, Depth=3.82" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 48698Paved parking, HSG B 6661>75% Grass cover, Good, HSG B 55294Weighted Average 6611.96% Pervious Area 48688.04% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=552 sf Runoff Volume=0.004 af Runoff Depth=3.82" Tc=6.0 min CN=94 0.05 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 65HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-9: CONTECH VORTSENTRY Runoff=0.26 cfs @ 12.08 hrs, Volume=0.020 af, Depth=4.15" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.50" Area (sf)CNDescription 1,34998Paved parking, HSG A 1,17298Paved parking, HSG B 5761>75% Grass cover, Good, HSG B 2,57897Weighted Average 572.21% Pervious Area 2,52197.79% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-9: CONTECH VORTSENTRY Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 10-Year Rainfall=4.50" Runoff Area=2,578 sf Runoff Volume=0.020 af Runoff Depth=4.15" Tc=6.0 min CN=97 0.26 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 66HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Area =2.280 ac,44.33% Impervious, Inflow Depth = 1.51" for 10-Year event Inflow=1.48 cfs @ 12.30 hrs, Volume=0.286 af Outflow=1.48 cfs @ 12.30 hrs, Volume=0.286 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Inflow Area=2.280 ac 1.48 cfs1.48 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 67HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-20: EX. PARKING LOT Inflow Area =0.133 ac,10.60% Impervious, Inflow Depth = 0.96" for 10-Year event Inflow=0.11 cfs @ 12.16 hrs, Volume=0.011 af Outflow=0.11 cfs @ 12.16 hrs, Volume=0.011 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-20: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.115 0.11 0.105 0.1 0.095 0.09 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Inflow Area=0.133 ac 0.11 cfs0.11 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 68HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 1P: U/G DETENTION ROOF Inflow Area =0.324 ac,90.83% Impervious, Inflow Depth = 3.82" for 10-Year event Inflow=1.36 cfs @ 12.08 hrs, Volume=0.103 af Outflow=0.29 cfs @ 12.50 hrs, Volume=0.077 af, Atten= 79%, Lag= 24.8 min Discarded=0.00 cfs @ 0.00 hrs, Volume=0.000 af Primary=0.29 cfs @ 12.50 hrs, Volume=0.077 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 195.30' @ 12.50 hrs Surf.Area= 940 sf Storage= 2,362 cf Plug-Flow detention time= 200.9 min calculated for 0.077 af (75% of inflow) Center-of-Mass det. time= 116.5 min ( 893.0 - 776.5 ) VolumeInvertAvail.StorageStorage Description #1A191.50'1,382 cf 20.00'W x 47.00'L x 5.50'H Field A 5,170 cf Overall - 1,716 cf Embedded = 3,454 cf x 40.0% Voids #2A192.50'1,716 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3192.50'214 cf 48.0" Round Pipe Storage -Impervious L= 17.0' 3,311 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary192.50'18.0" Round Culvert L= 128.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.50' / 191.30' S= 0.0094 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2Device 1193.68'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1195.31'3.5" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded191.50'2.410 in/hr Exfiltration X 0.00 over Wetted area Discarded OutFlow Max=0.00 cfs @ 0.00 hrs HW=191.50' (Free Discharge) 4=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.29 cfs @ 12.50 hrs HW=195.30' TW=191.56' (Dynamic Tailwater) 1=Culvert (Passes 0.29 cfs of 11.45 cfs potential flow) 2=Orifice/Grate (10-YR Storm Outlet) (Orifice Controls 0.29 cfs @ 5.90 fps) 3=Orifice/Grate (100-YR Storm Outlet) ( Controls 0.00 cfs) Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 69HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +15.00' Row Adjustment +4.00' Header x 2 = 43.00' Row Length +24.0" End Stone x 2 = 47.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +15.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,716.2 cf Chamber Storage 5,170.0 cf Field - 1,716.2 cf Chambers = 3,453.8 cf Stone x 40.0% Voids = 1,381.5 cf Stone Storage Chamber Storage + Stone Storage = 3,097.7 cf = 0.071 af Overall Storage Efficiency = 59.9% 3 Chambers 191.5 cy Field 127.9 cy Stone Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 70HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 1 0 Inflow Area=0.324 ac Peak Elev=195.30' Storage=2,362 cf 1.36 cfs 0.29 cfs 0.00 cfs 0.29 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 71HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 2.31" for 10-Year event Inflow=1.38 cfs @ 12.09 hrs, Volume=0.099 af Outflow=0.28 cfs @ 12.54 hrs, Volume=0.077 af, Atten= 79%, Lag= 26.7 min Discarded=0.00 cfs @ 0.00 hrs, Volume=0.000 af Primary=0.28 cfs @ 12.54 hrs, Volume=0.077 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 194.33' @ 12.54 hrs Surf.Area= 780 sf Storage= 1,904 cf Plug-Flow detention time= 169.0 min calculated for 0.077 af (78% of inflow) Center-of-Mass det. time= 85.6 min ( 913.1 - 827.5 ) VolumeInvertAvail.StorageStorage Description #1A190.50'1,150 cf 20.00'W x 39.00'L x 5.50'H Field A 4,290 cf Overall - 1,416 cf Embedded = 2,874 cf x 40.0% Voids #2A191.50'1,416 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3191.50'88 cf 48.0" Round Pipe Storage -Impervious L= 7.0' 2,653 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary191.50'18.0" Round Culvert L= 17.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.50' / 191.30' S= 0.0118 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf #2Device 1192.75'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1194.33'5.7" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded190.50'2.410 in/hr Exfiltration X 0.00 over Wetted area Discarded OutFlow Max=0.00 cfs @ 0.00 hrs HW=190.50' (Free Discharge) 4=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.28 cfs @ 12.54 hrs HW=194.33' TW=191.56' (Dynamic Tailwater) 1=Culvert (Passes 0.28 cfs of 12.27 cfs potential flow) 2=Orifice/Grate (10-YR Storm Outlet) (Orifice Controls 0.28 cfs @ 5.80 fps) 3=Orifice/Grate (100-YR Storm Outlet) ( Controls 0.00 cfs) Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 72HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +7.00' Row Adjustment +4.00' Header x 2 = 35.00' Row Length +24.0" End Stone x 2 = 39.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +7.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,415.5 cf Chamber Storage 4,290.0 cf Field - 1,415.5 cf Chambers = 2,874.5 cf Stone x 40.0% Voids = 1,149.8 cf Stone Storage Chamber Storage + Stone Storage = 2,565.3 cf = 0.059 af Overall Storage Efficiency = 59.8% 3 Chambers 158.9 cy Field 106.5 cy Stone Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 73HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 1 0 Inflow Area=0.514 ac Peak Elev=194.33' Storage=1,904 cf 1.38 cfs 0.28 cfs 0.00 cfs 0.28 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 74HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond CDS: CONTECH CDS Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 2.31" for 10-Year event Inflow=1.38 cfs @ 12.09 hrs, Volume=0.099 af Outflow=1.38 cfs @ 12.09 hrs, Volume=0.099 af, Atten= 0%, Lag= 0.0 min Primary=1.38 cfs @ 12.09 hrs, Volume=0.099 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 194.33' @ 12.53 hrs DeviceRouting InvertOutlet Devices #1Primary192.94'12.0" Round Culvert L= 9.5' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.94' / 192.75' S= 0.0200 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=1.38 cfs @ 12.09 hrs HW=193.60' TW=193.20' (Dynamic Tailwater) 1=Culvert (Barrel Controls 1.38 cfs @ 3.56 fps) Pond CDS: CONTECH CDS InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Inflow Area=0.514 ac Peak Elev=194.33' 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' 1.38 cfs1.38 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 75HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-1: STORM MH #1 Inflow Area =0.898 ac,64.01% Impervious, Inflow Depth > 2.34" for 10-Year event Inflow=0.64 cfs @ 12.36 hrs, Volume=0.175 af Outflow=0.64 cfs @ 12.36 hrs, Volume=0.175 af, Atten= 0%, Lag= 0.0 min Primary=0.64 cfs @ 12.36 hrs, Volume=0.175 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.21' @ 12.36 hrs DeviceRouting InvertOutlet Devices #1Primary190.84'18.0" Round Culvert L= 105.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 190.84' / 190.00' S= 0.0080 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=0.64 cfs @ 12.36 hrs HW=191.21' TW=0.00' (Dynamic Tailwater) 1=Culvert (Barrel Controls 0.64 cfs @ 2.90 fps) Pond MH-1: STORM MH #1 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.898 ac Peak Elev=191.21' 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' 0.64 cfs0.64 cfs Type III 24-hr 10-Year Rainfall=4.50"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 76HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-2: MH #2 Inflow Area =0.839 ac,61.63% Impervious, Inflow Depth > 2.21" for 10-Year event Inflow=0.57 cfs @ 12.52 hrs, Volume=0.154 af Outflow=0.57 cfs @ 12.52 hrs, Volume=0.154 af, Atten= 0%, Lag= 0.0 min Primary=0.57 cfs @ 12.52 hrs, Volume=0.154 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.56' @ 12.52 hrs DeviceRouting InvertOutlet Devices #1Primary191.20'18.0" Round Culvert L= 33.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.20' / 190.94' S= 0.0079 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=0.57 cfs @ 12.52 hrs HW=191.56' TW=191.20' (Dynamic Tailwater) 1=Culvert (Barrel Controls 0.57 cfs @ 2.62 fps) Pond MH-2: MH #2 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.839 ac Peak Elev=191.56' 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' 0.57 cfs0.57 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 77HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Time span=0.00-42.00 hrs, dt=0.01 hrs, 4201 points x 3 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Runoff Area=5,785 sf 10.60% Impervious Runoff Depth=2.10"Subcatchment P-1: AREA TRIBUTARY TO Flow Length=93' Tc=10.2 min CN=59 Runoff=0.27 cfs 0.023 af Runoff Area=5,355 sf 10.07% Impervious Runoff Depth=1.59"Subcatchment P-10: AREA TRIBUTARY TO Tc=6.0 min CN=53 Runoff=0.20 cfs 0.016 af Runoff Area=21,607 sf 38.22% Impervious Runoff Depth=2.74"Subcatchment P-2: AREA TRIBUTARY TO Flow Length=346' Tc=23.7 min CN=66 Runoff=0.98 cfs 0.113 af Runoff Area=14,129 sf 90.83% Impervious Runoff Depth=5.69"Subcatchment P-3: BLDG ADDITION & Tc=6.0 min CN=94 Runoff=1.98 cfs 0.154 af Runoff Area=33,248 sf 30.68% Impervious Runoff Depth=1.75"Subcatchment P-4: AREA TRIBUTARY TO Flow Length=223' Tc=10.0 min CN=55 Runoff=1.24 cfs 0.111 af Runoff Area=17,048 sf 38.42% Impervious Runoff Depth=3.63"Subcatchment P-5: CB #1 Tc=6.0 min CN=75 Runoff=1.66 cfs 0.118 af Runoff Area=1,653 sf 40.41% Impervious Runoff Depth=4.36"Subcatchment P-6: CB #3 Tc=6.0 min CN=82 Runoff=0.19 cfs 0.014 af Runoff Area=3,145 sf 62.73% Impervious Runoff Depth=5.12"Subcatchment P-7: CB #2 Tc=6.0 min CN=89 Runoff=0.41 cfs 0.031 af Runoff Area=552 sf 88.04% Impervious Runoff Depth=5.69"Subcatchment P-8: INLET OF CONTECH CDS Tc=6.0 min CN=94 Runoff=0.08 cfs 0.006 af Runoff Area=2,578 sf 97.79% Impervious Runoff Depth=6.04"Subcatchment P-9: CONTECH Tc=6.0 min CN=97 Runoff=0.37 cfs 0.030 af Inflow=4.14 cfs 0.546 afReach DP-10: WETLAND AREA NORTH OF PROJECT Outflow=4.14 cfs 0.546 af Inflow=0.27 cfs 0.023 afReach DP-20: EX. PARKING LOT Outflow=0.27 cfs 0.023 af Peak Elev=196.25' Storage=2,998 cf Inflow=1.98 cfs 0.154 afPond 1P: U/G DETENTION ROOF Discarded=0.00 cfs 0.000 af Primary=0.68 cfs 0.128 af Outflow=0.68 cfs 0.128 af Peak Elev=195.38' Storage=2,454 cf Inflow=2.35 cfs 0.169 afPond 2P: U/G DETENTION PARKING & Discarded=0.00 cfs 0.000 af Primary=1.25 cfs 0.147 af Outflow=1.25 cfs 0.147 af Peak Elev=195.50' Inflow=2.35 cfs 0.169 afPond CDS: CONTECH CDS 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' Outflow=2.35 cfs 0.169 af Peak Elev=191.52' Inflow=2.09 cfs 0.305 afPond MH-1: STORM MH #1 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' Outflow=2.09 cfs 0.305 af Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 78HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Peak Elev=191.92' Inflow=1.91 cfs 0.275 afPond MH-2: MH #2 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' Outflow=1.91 cfs 0.275 af Total Runoff Area = 2.413 ac Runoff Volume = 0.617 af Average Runoff Depth = 3.07" 57.53% Pervious = 1.388 ac 42.47% Impervious = 1.025 ac Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 79HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff=0.27 cfs @ 12.15 hrs, Volume=0.023 af, Depth=2.10" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 14198Paved parking, HSG A 60739>75% Grass cover, Good, HSG A 51032Woods/grass comb., Good, HSG A 8698Roofs, HSG B 38698Paved parking, HSG B 1,22561>75% Grass cover, Good, HSG B 2,83058Woods/grass comb., Good, HSG B 5,78559Weighted Average 5,17289.40% Pervious Area 61310.60% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 5.0290.02500.10 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 5.2640.00170.21 Shallow Concentrated Flow, Over Grass/Woods B-C Woodland Kv= 5.0 fps 10.293Total Subcatchment P-1: AREA TRIBUTARY TO EX. PARKING LOT Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=5,785 sf Runoff Volume=0.023 af Runoff Depth=2.10" Flow Length=93' Tc=10.2 min CN=59 0.27 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 80HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff=0.20 cfs @ 12.10 hrs, Volume=0.016 af, Depth=1.59" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 43998Paved parking, HSG A 1,18339>75% Grass cover, Good, HSG A 1,31732Woods/grass comb., Good, HSG A 10098Paved parking, HSG B 1,96561>75% Grass cover, Good, HSG B 35158Woods/grass comb., Good, HSG B 5,35553Weighted Average 4,81689.93% Pervious Area 53910.07% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-10: AREA TRIBUTARY TO WETLAND Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.22 0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=5,355 sf Runoff Volume=0.016 af Runoff Depth=1.59" Tc=6.0 min CN=53 0.20 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 81HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff=0.98 cfs @ 12.35 hrs, Volume=0.113 af, Depth=2.74" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 5,57998Paved parking, HSG A 5,17139>75% Grass cover, Good, HSG A 2,69232Woods/grass comb., Good, HSG A 43598Roofs, HSG B 2,24598Paved parking, HSG B 5,48558Woods/grass comb., Good, HSG B 21,60766Weighted Average 13,34861.78% Pervious Area 8,25938.22% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 20.9790.00520.06 Sheet Flow, Over Grass/Woods A-B Grass: Dense n= 0.240 P2= 3.00" 2.82670.00621.60 Shallow Concentrated Flow, Over Pavement B-C Paved Kv= 20.3 fps 23.7346Total Subcatchment P-2: AREA TRIBUTARY TO INLET AT COLES MEADOW RD & N. KING ST Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=21,607 sf Runoff Volume=0.113 af Runoff Depth=2.74" Flow Length=346' Tc=23.7 min CN=66 0.98 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 82HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff=1.98 cfs @ 12.08 hrs, Volume=0.154 af, Depth=5.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 7,00698Roofs, HSG A 6498Paved parking, HSG A 19239>75% Grass cover, Good, HSG A 4,79698Roofs, HSG B 96898Paved parking, HSG B 1,10361>75% Grass cover, Good, HSG B 14,12994Weighted Average 1,2959.17% Pervious Area 12,83490.83% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-3: BLDG ADDITION & COURTYARD Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=14,129 sf Runoff Volume=0.154 af Runoff Depth=5.69" Tc=6.0 min CN=94 1.98 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 83HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff=1.24 cfs @ 12.15 hrs, Volume=0.111 af, Depth=1.75" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 1,45098Roofs, HSG A 8,58398Paved parking, HSG A 11,39639>75% Grass cover, Good, HSG A 10,73132Woods/grass comb., Good, HSG A 16698Paved parking, HSG B 92258Woods/grass comb., Good, HSG B 33,24855Weighted Average 23,04969.32% Pervious Area 10,19930.68% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 8.8560.02300.11 Sheet Flow, Over Grass A-B Grass: Dense n= 0.240 P2= 3.00" 1.11450.01802.16 Shallow Concentrated Flow, Over Grass/Woods B-C Unpaved Kv= 16.1 fps 0.1220.03003.52 Shallow Concentrated Flow, Over Pavement C-D Paved Kv= 20.3 fps 10.0223Total Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 84HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Subcatchment P-4: AREA TRIBUTARY TO N. KING STREET Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=33,248 sf Runoff Volume=0.111 af Runoff Depth=1.75" Flow Length=223' Tc=10.0 min CN=55 1.24 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 85HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-5: CB #1 Runoff=1.66 cfs @ 12.09 hrs, Volume=0.118 af, Depth=3.63" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 19198Paved parking, HSG A *58070Porous Pavement, HSG A 43898Roofs, HSG B 5,92098Paved parking, HSG B 6,27461>75% Grass cover, Good, HSG B 3,13858Woods/grass comb., Good, HSG B *50775Porous Pavement, HSG B 17,04875Weighted Average 10,49961.58% Pervious Area 6,54938.42% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-5: CB #1 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=17,048 sf Runoff Volume=0.118 af Runoff Depth=3.63" Tc=6.0 min CN=75 1.66 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 86HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-6: CB #3 Runoff=0.19 cfs @ 12.09 hrs, Volume=0.014 af, Depth=4.36" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 66898Paved parking, HSG B 28561>75% Grass cover, Good, HSG B *70075Porous Pavement, HSG B 1,65382Weighted Average 98559.59% Pervious Area 66840.41% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-6: CB #3 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=1,653 sf Runoff Volume=0.014 af Runoff Depth=4.36" Tc=6.0 min CN=82 0.19 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 87HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-7: CB #2 Runoff=0.41 cfs @ 12.08 hrs, Volume=0.031 af, Depth=5.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 1098Paved parking, HSG A *1770Porous Pavement, HSG A 1,96398Paved parking, HSG B 14461>75% Grass cover, Good, HSG B *1,01175Porous Pavement, HSG B 3,14589Weighted Average 1,17237.27% Pervious Area 1,97362.73% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-7: CB #2 Runoff Hydrograph Time (hours)4241403938373635343332313029282726252423222120191817161514131211109876543210 Flo w ( c f s ) 0.46 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=3,145 sf Runoff Volume=0.031 af Runoff Depth=5.12" Tc=6.0 min CN=89 0.41 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 88HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff=0.08 cfs @ 12.08 hrs, Volume=0.006 af, Depth=5.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 48698Paved parking, HSG B 6661>75% Grass cover, Good, HSG B 55294Weighted Average 6611.96% Pervious Area 48688.04% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-8: INLET OF CONTECH CDS #2 Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=552 sf Runoff Volume=0.006 af Runoff Depth=5.69" Tc=6.0 min CN=94 0.08 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 89HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Subcatchment P-9: CONTECH VORTSENTRY Runoff=0.37 cfs @ 12.08 hrs, Volume=0.030 af, Depth=6.04" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=6.40" Area (sf)CNDescription 1,34998Paved parking, HSG A 1,17298Paved parking, HSG B 5761>75% Grass cover, Good, HSG B 2,57897Weighted Average 572.21% Pervious Area 2,52197.79% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment P-9: CONTECH VORTSENTRY Runoff Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type III 24-hr 100-Year Rainfall=6.40" Runoff Area=2,578 sf Runoff Volume=0.030 af Runoff Depth=6.04" Tc=6.0 min CN=97 0.37 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 90HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Area =2.280 ac,44.33% Impervious, Inflow Depth = 2.87" for 100-Year event Inflow=4.14 cfs @ 12.19 hrs, Volume=0.546 af Outflow=4.14 cfs @ 12.19 hrs, Volume=0.546 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-10: WETLAND AREA NORTH OF PROJECT Inflow Outflow Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Inflow Area=2.280 ac 4.14 cfs4.14 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 91HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Reach DP-20: EX. PARKING LOT Inflow Area =0.133 ac,10.60% Impervious, Inflow Depth = 2.10" for 100-Year event Inflow=0.27 cfs @ 12.15 hrs, Volume=0.023 af Outflow=0.27 cfs @ 12.15 hrs, Volume=0.023 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Reach DP-20: EX. PARKING LOT Inflow Outflow Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=0.133 ac 0.27 cfs0.27 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 92HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 1P: U/G DETENTION ROOF Inflow Area =0.324 ac,90.83% Impervious, Inflow Depth = 5.69" for 100-Year event Inflow=1.98 cfs @ 12.08 hrs, Volume=0.154 af Outflow=0.68 cfs @ 12.35 hrs, Volume=0.128 af, Atten= 66%, Lag= 16.1 min Discarded=0.00 cfs @ 0.00 hrs, Volume=0.000 af Primary=0.68 cfs @ 12.35 hrs, Volume=0.128 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 196.25' @ 12.35 hrs Surf.Area= 940 sf Storage= 2,998 cf Plug-Flow detention time= 169.9 min calculated for 0.128 af (83% of inflow) Center-of-Mass det. time= 101.3 min ( 868.1 - 766.8 ) VolumeInvertAvail.StorageStorage Description #1A191.50'1,382 cf 20.00'W x 47.00'L x 5.50'H Field A 5,170 cf Overall - 1,716 cf Embedded = 3,454 cf x 40.0% Voids #2A192.50'1,716 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3192.50'214 cf 48.0" Round Pipe Storage -Impervious L= 17.0' 3,311 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary192.50'18.0" Round Culvert L= 128.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.50' / 191.30' S= 0.0094 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2Device 1193.68'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1195.31'3.5" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded191.50'2.410 in/hr Exfiltration X 0.00 over Wetted area Discarded OutFlow Max=0.00 cfs @ 0.00 hrs HW=191.50' (Free Discharge) 4=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.68 cfs @ 12.35 hrs HW=196.25' TW=191.90' (Dynamic Tailwater) 1=Culvert (Passes 0.68 cfs of 13.44 cfs potential flow) 2=Orifice/Grate (10-YR Storm Outlet) (Orifice Controls 0.37 cfs @ 7.53 fps) 3=Orifice/Grate (100-YR Storm Outlet) (Orifice Controls 0.31 cfs @ 4.66 fps) Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 93HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +15.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +15.00' Row Adjustment +4.00' Header x 2 = 43.00' Row Length +24.0" End Stone x 2 = 47.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +15.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,716.2 cf Chamber Storage 5,170.0 cf Field - 1,716.2 cf Chambers = 3,453.8 cf Stone x 40.0% Voids = 1,381.5 cf Stone Storage Chamber Storage + Stone Storage = 3,097.7 cf = 0.071 af Overall Storage Efficiency = 59.9% 3 Chambers 191.5 cy Field 127.9 cy Stone Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 94HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 1P: U/G DETENTION ROOF Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 2 1 0 Inflow Area=0.324 ac Peak Elev=196.25' Storage=2,998 cf 1.98 cfs 0.68 cfs 0.00 cfs 0.68 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 95HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 3.94" for 100-Year event Inflow=2.35 cfs @ 12.09 hrs, Volume=0.169 af Outflow=1.25 cfs @ 12.22 hrs, Volume=0.147 af, Atten= 47%, Lag= 8.2 min Discarded=0.00 cfs @ 0.00 hrs, Volume=0.000 af Primary=1.25 cfs @ 12.22 hrs, Volume=0.147 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 195.38' @ 12.22 hrs Surf.Area= 780 sf Storage= 2,454 cf Plug-Flow detention time= 121.5 min calculated for 0.147 af (87% of inflow) Center-of-Mass det. time= 63.1 min ( 876.4 - 813.3 ) VolumeInvertAvail.StorageStorage Description #1A190.50'1,150 cf 20.00'W x 39.00'L x 5.50'H Field A 4,290 cf Overall - 1,416 cf Embedded = 2,874 cf x 40.0% Voids #2A191.50'1,416 cf CMP_Round 48 x 3 Inside #1 Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 16.00' Header x 12.53 sf x 2 = 400.9 cf Inside #3191.50'88 cf 48.0" Round Pipe Storage -Impervious L= 7.0' 2,653 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary191.50'18.0" Round Culvert L= 17.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.50' / 191.30' S= 0.0118 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf #2Device 1192.75'3.0" Vert. Orifice/Grate (10-YR Storm Outlet) C= 0.600 #3Device 1194.33'5.7" Horiz. Orifice/Grate (100-YR Storm Outlet) C= 0.600 Limited to weir flow at low heads #4Discarded190.50'2.410 in/hr Exfiltration X 0.00 over Wetted area Discarded OutFlow Max=0.00 cfs @ 0.00 hrs HW=190.50' (Free Discharge) 4=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=1.25 cfs @ 12.22 hrs HW=195.38' TW=191.92' (Dynamic Tailwater) 1=Culvert (Passes 1.25 cfs of 15.06 cfs potential flow) 2=Orifice/Grate (10-YR Storm Outlet) (Orifice Controls 0.37 cfs @ 7.62 fps) 3=Orifice/Grate (100-YR Storm Outlet) (Orifice Controls 0.88 cfs @ 4.94 fps) Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 96HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY - Chamber Wizard Field A Chamber Model = CMP_Round 48 (Round Corrugated Metal Pipe) Effective Size= 48.0"W x 48.0"H => 12.53 sf x 20.00'L = 250.5 cf Overall Size= 48.0"W x 48.0"H x 20.00'L Row Length Adjustment= +7.00' x 12.53 sf x 3 rows 48.0" Wide + 24.0" Spacing = 72.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +7.00' Row Adjustment +4.00' Header x 2 = 35.00' Row Length +24.0" End Stone x 2 = 39.00' Base Length 3 Rows x 48.0" Wide + 24.0" Spacing x 2 + 24.0" Side Stone x 2 = 20.00' Base Width 12.0" Base + 48.0" Chamber Height + 6.0" Cover = 5.50' Field Height 3 Chambers x 250.5 cf +7.00' Row Adjustment x 12.53 sf x 3 Rows + 16.00' Header x 12.53 sf x 2 = 1,415.5 cf Chamber Storage 4,290.0 cf Field - 1,415.5 cf Chambers = 2,874.5 cf Stone x 40.0% Voids = 1,149.8 cf Stone Storage Chamber Storage + Stone Storage = 2,565.3 cf = 0.059 af Overall Storage Efficiency = 59.8% 3 Chambers 158.9 cy Field 106.5 cy Stone Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 97HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Pond 2P: U/G DETENTION PARKING & DRIVEWAY Inflow Outflow DiscardedPrimary Hydrograph Time (hours)424038363432302826242220181614121086420 Fl o w ( c f s ) 2 1 0 Inflow Area=0.514 ac Peak Elev=195.38' Storage=2,454 cf 2.35 cfs 1.25 cfs 0.00 cfs 1.25 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 98HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond CDS: CONTECH CDS Inflow Area =0.514 ac,43.20% Impervious, Inflow Depth = 3.94" for 100-Year event Inflow=2.35 cfs @ 12.09 hrs, Volume=0.169 af Outflow=2.35 cfs @ 12.09 hrs, Volume=0.169 af, Atten= 0%, Lag= 0.0 min Primary=2.35 cfs @ 12.09 hrs, Volume=0.169 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 195.50' @ 12.20 hrs DeviceRouting InvertOutlet Devices #1Primary192.94'12.0" Round Culvert L= 9.5' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 192.94' / 192.75' S= 0.0200 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=2.34 cfs @ 12.09 hrs HW=195.11' TW=194.73' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.34 cfs @ 2.98 fps) Pond CDS: CONTECH CDS InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Inflow Area=0.514 ac Peak Elev=195.50' 12.0" Round Culvert n=0.013 L=9.5' S=0.0200 '/' 2.35 cfs2.35 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 99HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-1: STORM MH #1 Inflow Area =0.898 ac,64.01% Impervious, Inflow Depth = 4.07" for 100-Year event Inflow=2.09 cfs @ 12.21 hrs, Volume=0.305 af Outflow=2.09 cfs @ 12.21 hrs, Volume=0.305 af, Atten= 0%, Lag= 0.0 min Primary=2.09 cfs @ 12.21 hrs, Volume=0.305 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.52' @ 12.21 hrs DeviceRouting InvertOutlet Devices #1Primary190.84'18.0" Round Culvert L= 105.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 190.84' / 190.00' S= 0.0080 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=2.09 cfs @ 12.21 hrs HW=191.52' TW=0.00' (Dynamic Tailwater) 1=Culvert (Barrel Controls 2.09 cfs @ 3.91 fps) Pond MH-1: STORM MH #1 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Inflow Area=0.898 ac Peak Elev=191.52' 18.0" Round Culvert n=0.013 L=105.0' S=0.0080 '/' 2.09 cfs2.09 cfs Type III 24-hr 100-Year Rainfall=6.40"14-046_Post_DRN Printed 2/9/2015Prepared by ProTerra Design Group, LLC Page 100HydroCAD® 10.00-12 s/n 07277 © 2014 HydroCAD Software Solutions LLC Summary for Pond MH-2: MH #2 Inflow Area =0.839 ac,61.63% Impervious, Inflow Depth = 3.93" for 100-Year event Inflow=1.91 cfs @ 12.25 hrs, Volume=0.275 af Outflow=1.91 cfs @ 12.25 hrs, Volume=0.275 af, Atten= 0%, Lag= 0.0 min Primary=1.91 cfs @ 12.25 hrs, Volume=0.275 af Routing by Dyn-Stor-Ind method, Time Span= 0.00-42.00 hrs, dt= 0.01 hrs / 3 Peak Elev= 191.92' @ 12.24 hrs DeviceRouting InvertOutlet Devices #1Primary191.20'18.0" Round Culvert L= 33.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 191.20' / 190.94' S= 0.0079 '/' Cc= 0.900 n= 0.013, Flow Area= 1.77 sf Primary OutFlow Max=1.91 cfs @ 12.25 hrs HW=191.92' TW=191.52' (Dynamic Tailwater) 1=Culvert (Outlet Controls 1.91 cfs @ 3.32 fps) Pond MH-2: MH #2 InflowPrimary Hydrograph Time (hours) 4241403938373635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Inflow Area=0.839 ac Peak Elev=191.92' 18.0" Round Culvert n=0.013 L=33.0' S=0.0079 '/' 1.91 cfs1.91 cfs Section 4 Stormwater Management Calculations RECHARGE TO GROUNDWATER    The calculation for the Required Recharge Volume is done using the equations in the 2008  Massachusetts Stormwater Handbook. The Required Recharge Volume equals a depth of  runoff corresponding to the soil type times the new impervious areas covering that soil type  at the post development site. The Required Recharge Volume is based on the Static method.  The infiltration BMPs proposed are porous pavement with infiltration and underground  detention basins with infiltration.  For the purposes of these calculations the porous  pavement was not considered for recharge or storage volume.    Rv = F x impervious area (Equation 1) Volume 3, Ch 1, page 15  Rv = Required Recharge Volume, expressed in cubic feet, cubic yards, or acre‐feet  F = Target Depth Factor associated with each Hydrologic Soil Group (HSG)    Impervious Area (A Soils) = new building roof & new pavement = 10,179 sf  Impervious Ares (B Soils) = new building roof & new pavement = 14,527 sf    (imp% = (10,179 sf + 14,527 sf) /82,350 sf = 30.0% considering proposed work only)    F for A soils = 0.60 inches (Table 2.3.2) Volume 3, Ch 1, page 16  F for B soils = 0.35 inches  F for C soils = 0.25 inches  F for D soils = 0.10 inches    Using the formula above, the following table shows the site’s proposed impervious surface  area overlying particular Hydrologic Soil Groups and the calculated Required Recharge  Volume. The NRCS soil report for the site and infiltration BMP location shows loamy sand.  The corresponding Hydrologic Soil Groups are estimated as HSG A & B and F values of 0.60  inches (or 0.050 feet) and 0.35 inches (or 0.029 feet) was used, respectively.    RvA = F x impervious area = 0.050’ X 10179 sf = 509 cf (A Soils)  RvB = F x impervious area = 0.029’ X 14527 sf = 422 cf (B Soils)    RvTotal = RvA + RvB = 509 cf + 422 cf = 931 cf (Total)    The proposed site does not have all impervious surface stormwater runoff directed to  infiltration BMPs – adjustment required.     Impervious Area Draining to Infiltration BMPs = 20,092 sf  Total Site Impervious Area / Impervious Area Draining to Infiltration BMPs  = 24,706 sf / 20,092 sf = 1.23    Adjusted Minimum RvTotal = 1.23 * 931 cf = 1,146 cf (Adjusted Total)            WATER QUALITY VOLUME    The following calculation summarizes the tributary area and 0.5” equivalent water quality  volume generated.  The proposed paved parking areas generate runoff for pretreatment by  a hydrodynamic separator before discharge to the underground stormwater detention and  infiltration system #2 (parking & driveway) and eventually the surrounding property.    WQV = WQD x Impervious Area    WQV = Water Quality Volume    WQD = Water Quality Depth, 0.5” or 1” if critical area    Impervious Area = impervious tributary to treatment train      WQVparking = 0.5” / (12”/’) x 22,398 sf = 934 cf    WQVdrive = 0.5” / (12”/’) x 2,578 sf = 108 cf   (Leaves site un‐detained after hydrodynamic separator)    Volume provided in underground stormwater detention and infiltration system #2 (parking  & driveway) = 952 cf (See HydroCAD Calculations volume)    952 cf > 934 cf Therefore OK                                              EVALUATION OF INFILTRATION FEASIBILITY  (UNDERGROUND STORMWATER DETENTION & INFILTRATION SYSTEM #1)    Table 1 – Infiltration Feasibility    Criteria Status  Infiltration rate greater than or equal to 0.17  inches/hour  Infiltration rate is estimated at 2.41 inches/hour from  Rawl’s  Loamy Sand (to be used based on existing soil  logs see Section 5 for data)  Soils have a clay content of less than 20% and a  silt/clay content of less than 40%  Loamy Sand Infiltration on slopes less than 6% Infiltration basin laid no more than 2% slope  Bottom of infiltration must be separated at least 2  feet from groundwater  No groundwater observed during deep observation  hole logs prepared for previous drainage system  design in 2007.  Facility located 100 feet from a well No known wells within 100’ Maximum contributing area less than 5 acres Tributary Area = 0.324 acres Setback 20 feet down‐gradient from structures Downgradient of structures.      Determine the required surface area of underground stormwater detention and infiltration  system #1 (roof) to meet the design constraints.  Because the underground detention  facilities were design for storage of larger storm events, it was assumed that each basin  could handle the entire proposed project required recharge volume.    )12/(sin kTnD WQvaSurfaceAreBa          Maryland Department of Natural Resources 1984     Where:   WQv = Required Recharge Volume = 1,146 cf,    k = Saturated Hydraulic Conductivity, in/hr = 2.41 in/hr  T = Fill Time, hours, 2 hours  d = underground stormwater detention Depth, ft, 5.5 feet  n = Porosity, 40%    )/'"12/2*41.25.5*40.0( )146,1( sin BaaSurfaceAre     Surface Area Required = 441 sf    Surface Area Underground Stormwater Detention and infiltration system #1 (roof)  Provided = 940 sf > 441 sf – OK    Depth to bedrock and groundwater confirmed based on existing soil data attached in  Section 5.          VOLUME AVAILABLE ‐   (UNDERGROUND STORMWATER DETENTION & INFILTRATION SYSTEM #1)    Based on calculations from the HydroCAD model, the storage volume for the underground  stormwater detention and infiltration system #1 (roof) allows 3,311 cf of stormwater to be  infiltrated and stored.  Because the underground detention facilities were design for storage  of larger storm events, it was assumed that each basin could handle the entire proposed  project required recharge volume.    Total Storage volume available for Recharge    Underground Stormwater Detention and Infiltration System #2 (parking & driveway)  Volume = 3,311 cf > 1146 cf RvTotal ‐ OK    DRAWDOWN TIME    Below are the drawdown time calculations for the infiltration systems proposed on the site.   The calculations use K values of 2.41 inches per hour as shown on the Rawl’s table (Chapter  1 page 22) for Textural Class Loamy Sand in the HydroCAD model.      ))((AreaBottomK VTimedrawdown          Volume 3, Ch 1, pages 25  Where:  V = Storage Volume *  K = Saturated Hydraulic Conductivity, Rawls Rate  Bottom Area = Bottom Area of Recharge Structure     * The Storage Volume calculated in the HydroCAD model assumed to be the storage  available in the Underground Stormwater Detention and Infiltration System #2 (parking &  driveway).    )940)(/'"12/41.2( )3311( sf cfTimedrawdown  Time hrs drawdown = 17.5 hours    Underground System #1 (roof) Drain Down Time Calc 18 hrs    Underground System #1 (roof)  Drain Down Time Calc @ 2.41 in/hr 18 hrs        The calculations show that the Underground Stormwater Detention and Infiltration System  #1 (roof) will drawdown within the required 72 hours between storm events.   EVALUATION OF INFILTRATION FEASIBILITY  (UNDERGROUND STORMWATER DETENTION & INFILTRATION SYSTEM #2)    Table 1 – Infiltration Feasibility    Criteria Status  Infiltration rate greater than or equal to 0.17 inches/hour  Infiltration rate is estimated at 2.41 inches/hour from  Rawl’s  Loamy Sand (to be used based on existing soil  logs see Section 5 for data)  Soils have a clay content of less than 20% and a  silt/clay content of less than 40%  Loamy Sand Infiltration on slopes less than 6% Porous Pavement slope is about 2‐4%; Infiltration  basin laid no more than 2% slope  Bottom of infiltration must be separated at least 2  feet from groundwater  No groundwater observed during deep observation  hole logs prepared for previous drainage system  design in 2007.  Facility located 100 feet from a well No known wells within 100’ Maximum contributing area less than 5 acres Tributary Area = 0.514 acres Setback 20 feet down‐gradient from structures Downgradient of structures.     Determine the required surface area of underground stormwater detention and infiltration  system #2 (parking & driveway) to meet the design constraints.  Because the underground  detention facilities were design for storage of larger storm events, it was assumed that each  basin could handle the entire proposed project required recharge volume.    )12/(sin kTnD WQvaSurfaceAreBa          Maryland Department of Natural Resources 1984     Where:   WQv = Water Quality Volume = 934 cf < Required Recharge Volume = 1,146 cf,     use 1,146 cf  k = Saturated Hydraulic Conductivity, in/hr = 2.41 in/hr  T = Fill Time, hours, 2 hours  d = underground stormwater detention Depth, ft, 5.5 feet  n = Porosity, 40%    )/'"12/2*41.25.5*40.0( )146,1( sin BaaSurfaceAre     Surface Area Required = 441 sf    Surface Area Underground Stormwater Detention and infiltration system #2 (parking &  driveway) Provided = 780 sf > 441 sf – OK    Depth to bedrock and groundwater confirmed based on existing soil data attached in  Section 5.      VOLUME AVAILABLE ‐   (UNDERGROUND STORMWATER DETENTION & INFILTRATION SYSTEM #2)    Based on calculations from the HydroCAD model, the storage volume for the underground  stormwater detention and infiltration system #2 (parking & driveway) allows 2,653 cf of  stormwater to be infiltrated and stored.  Because the underground detention facilities were  design for storage of larger storm events, it was assumed that each basin could handle the  entire proposed project required recharge volume.    Total Storage volume available for Recharge    Underground Stormwater Detention and Infiltration System #2 (parking & driveway)  Volume = 2,653 cf > 1146 cf RvTotal and 934 cf WQV ‐ OK    DRAWDOWN TIME    Below are the drawdown time calculations for the infiltration systems proposed on the site.   The calculations use K values of 2.41 inches per hour as shown on the Rawl’s table (Chapter  1 page 22) for Textural Class Loamy Sand in the HydroCAD model.      ))((AreaBottomK VTimedrawdown          Volume 3, Ch 1, pages 25  Where:  V = Storage Volume *  K = Saturated Hydraulic Conductivity, Rawls Rate  Bottom Area = Bottom Area of Recharge Structure     * The Storage Volume calculated in the HydroCAD model assumed to be the storage  available in the Underground Stormwater Detention and Infiltration System #2 (parking &  driveway).    )780)(/'"12/41.2( )2653( sf cfTimedrawdown  Time hrs drawdown = 16.9 hours    Underground System #2 (parking & driveway) Drain Down Time Calc 17 hrs    Underground System #2 (parking & driveway)  Drain Down Time Calc @ 2.41 in/hr 17 hrs        The calculations show that the Underground Stormwater Detention and Infiltration System  #2 (parking & driveway) will drawdown within the required 72 hours between storm events. Ba s e d u p o n L e v e l S p r e a d e r D e s i g n G u i d e l i n e s f r o m M a s s . E r o s i o n & S e d i m e n t C o n t r o l G u i d e l i n e s f o r U r b a n & S u b u r b a n L a n d a n d NR C S C o n s e r v a t i o n P r a c t i c e S t a n d a r d C o d e 8 7 0 Sh a r p - c r e s t e d Fr o m O u t l e t F l o w ( c f s ) We i r W i d t h 1 C a l c u l a t e d (f t ) De s i g n W i d t h ( f t ) St o r m S e w e r S y s t e m Ou t l e t P i p e 2. 0 9 8 . 6 1 0 1 ca l c u l a t e d w e i r w i d t h f o r m a x 2 - 3 " H e i g h t o v e r s h a r p c r e s t e d w e ir o n 1 0 0 - y e a r e v e n t ( b a s e d u p o n M a s s D e s i g n G u i d e l i n e o f 6 " w i t h 1 0 f o o t m i n i m u m w i d t h ) Q = C L e H ^ ( 3 / 2 ) = m i t i g a t e d 1 0 0 y r S C S 2 4 - h r D e s i g n S t o r m C = C o e f f i c i e n t , 3 . 4 7 Le = E f f e c t i v e L e n g t h V a r i a b l e , S o l v e H = 0 . 1 7 ' ( 2 " h e i g h t o v e r s p r e a d e r ) LE V E L S P R E A D E R D E S I G N 10 0 - Y R IN S T R U C T I O N S : No n - a u t o m a t e d : M a r . 4 , 2 0 0 8 1. S h e e t i s n o n a u t o m a t e d . P r i n t s h e e t a n d c o m p l e t e u s i n g h a n d c al c u l a t i o n s . C o l u m n A a n d B : S e e M a s s D E P S t r u c t u r a l B M P T a b l e 2. T h e c a l c u l a t i o n s m u s t b e c o m p l e t e d u s i n g t h e C o l u m n H e a d i n g s s p e c i f i e d i n C h a r t a n d N o t t h e E x c e l C o l u m n H e a d i n g s 3. T o c o m p l e t e C h a r t C o l u m n D , m u l t i p l e C o l u m n B v a l u e w i t h i n R ow x C o l u m n C v a l u e w i t h i n R o w 4. T o c o m p l e t e C h a r t C o l u m n E v a l u e , s u b t r a c t C o l u m n D v a l u e w i th i n R o w f r o m C o l u m n C w i t h i n R o w 5. T o t a l T S S R e m o v a l = S u m A l l V a l u e s i n C o l u m n D Lo c a t i o n : AB C D E TS S R e m o v a l S t a r t i n g T S S A m o u n t R e m a i n i n g BM P 1 Ra t e 1 Lo a d * R e m o v e d ( B * C ) L o a d ( C - D ) Po r o u s P a v e m e n t 0. 0 0 1 . 0 0 0 . 0 0 1 . 0 0 De e p S u m p a n d H o o d e d Ca t c h B a s i n 0. 2 5 1 . 0 0 0 . 2 5 0 . 7 5 Pr o p r i e t a r y T r e a t m e n t Pr a c t i c e 0. 6 0 0 . 7 5 0 . 4 5 0 . 3 0 Su b s u r f a c e I n f i l t r a t i o n St r u c t u r e 0. 8 0 0 . 3 0 0 . 2 4 0 . 0 6 0. 0 0 0 . 0 6 0 . 0 0 0 . 0 6 To t a l T S S R e m o v a l = 94 % Se p a r a t e F o r m N e e d s t o be C o m p l e t e d f o r E a c h Ou t l e t o r B M P T r a i n Pr o j e c t : Pro p o s e d Ad d i t i on to Roc krid ge Re t i r e m e n t F a c i l i t y Pr e p a r e d B y : BL M *E q u a l s r e m a i n i n g l o a d f r o m p r e v i o u s B M P ( E ) Da t e : 2/ 1 0 / 2 0 1 5 wh i c h e n t e r s t h e B M P No r t h a m p t o n , M A TSS Removal Calculation Worksheet No n - a u t o m a t e d T S S C a l c u l a t i o n S h e e t m u s t b e u s e d i f P r o p r i e t a r y B M P P r o p o s e d 1. F r o m M a s s D E P S t o r m w a t e r H a n d b o o k V o l . 1 Ma s s . D e p t . o f E n v i r o n m e n t a l P r o t e c t i o n BMP TREATMENT TRAIN  Porous Pavement with Street Sweeping*  0% Paved Parking Stalls & Driveway  with Street Sweeping*   (22,398SF)  Deep Sump and Hooded Catch Basin  25% DP‐10 94% TSS Removal (22,398 SF)  60% TSS Removal (2,578 SF)  TSS Removal Weighted Average =            ((0.94*22398)+(0.60*2578))/24,976=90%    *No credit taken for porous pavement or  street sweeping.  Subsurface Infiltration Structure  80% Proprietary Treatment Practice  60% Proprietary  Treatment Practice  60%  Paved Parking Stalls  & Driveway with  Street Sweeping*  (2,578 SF)  Area0.51acresCDS Model Weighted C0.90 2015-4 50microns Tc6minutesCDS Treatment Capacity 0.7cfs 1.4cfs Rainfall Intensity1 (in/hr) Percent Rainfall Volume1 Cumulative Rainfall Volume Total Flowrate (cfs) Treated Flowrate (cfs) Removal Efficiency (%) Incremental Removal (%) 0.0210.2%10.2%0.010.0196.89.8 0.049.6%19.8%0.020.0296.39.3 0.069.4%29.3%0.030.0395.99.1 0.087.7%37.0%0.040.0495.47.4 0.108.6%45.6%0.050.0595.08.1 0.126.3%51.9%0.060.0694.56.0 0.144.7%56.5%0.060.0694.14.4 0.164.6%61.2%0.070.0793.64.3 0.183.5%64.7%0.080.0893.23.3 0.204.3%69.1%0.090.0992.84.0 0.258.0%77.1%0.110.1191.67.3 0.305.6%82.7%0.140.1490.55.1 0.354.4%87.0%0.160.1689.43.9 0.402.5%89.5%0.180.1888.32.2 0.452.5%92.1%0.210.2187.22.2 0.501.4%93.5%0.230.2386.11.2 0.755.0%98.5%0.340.3480.54.1 1.001.0%99.5%0.460.4674.90.8 1.500.0%99.5%0.690.6963.70.0 2.000.0%99.5%0.920.9252.60.0 3.000.5%100.0%1.381.3830.20.1 92.6 6.5% 93.5% 86.2% 1 - Based on 10 years of hourly precipitation data from NCDC Station 770, Boston WSFO AP, Suffolk County, MA 2 - Reduction due to use of 60-minute data for a site that has a time of concentration less than 30-minutes. BASED ON THE RATIONAL RAINFALL METHOD for SYSTEM: CDS 2015-4 #2 CDS ESTIMATED NET ANNUAL TSS REDUCTION ADDITION TO ROCKRIDGE RETIREMENT FACILITY NORTHAMPTON, MA Predicted Net Annual Load Removal Efficiency = BASED ON AN AVERAGE PARTICLE SIZE OF 50 MICRONS Removal Efficiency Adjustment2 = Predicted % Annual Rainfall Treated = environmental Independent Review of CDS 2015 Product Evaluation Report by FB Environmental Associates, Inc. 97A Exchange St. Portland ME 04101 environmental November 5, 2009 2 FB Environmental Associates, Inc Introduction FB Environmental Associates, Inc. (FB Environmental), was hired by Contech Construction Products, Inc. (Contech), in 2009 to serve as an independent reviewer of testing conducted on the CDS2015 test unit. The CDS2015 is a stormwater treatment device intended to remove pollutants, including suspended solids, from stormwater. Flow up to the treatment design capacity is guided by a diversion weir into a separation chamber for treatment. The primary methods used to remove pollutants are swirl concentration, a continuous deflective separation screen, and an oil baffle. Flows which exceed the treatment design capacity flow around the separation chamber. A diagram of a CDS unit is shown in Figure 1. The CDS2015 test unit was tested across flow rates ranging from 0.12 to 1.8 cfs. Tests were conducted under controlled conditions, and repeated three times at each target flow rate, with FB Environmental serving as a third-party, independent reviewer. Our role was to observe all test runs and sample collection, review data records and calculations, and state whether tests conformed to the written protocol provided by Contech. Figure 1: Design and construction of the CDS unit. environmental November 5, 2009 3 FB Environmental Associates, Inc Procedure Contaminant A commercial sand product, OK-110, was used to provide a standardized contaminant for solids removal testing. This product was manufactured by the US Silica Company1 and the materials used for testing originated from the Mill Creek, OK plant. OK-110 is a natural silica sand product (SG=2.65) consisting of unground sand that has been processed to produce a distribution of particles between 50-µm and 200-µm with a d50 of approximately 105-µm. A particle size distribution for OK-110 is shown in Figure 2, revealing a texture (USDA scale) consisting of 100% sand, 0% silt, and 0% clay-sized particles. Figure 2: Particle size distribution of OK-110 based upon manufacturer's specifications (US Silica, ND). Test Apparatus Removal Efficiency Testing The CDS consists of a swirl concentrator and deflective screen and is shown in Figure 1. During operation, water enters the CDS unit’s diversion chamber where the diversion weir guides the flow into the unit’s separation chamber and pollutants are removed. All flows up to the system’s design capacity enter the separation chamber, while higher flows are bypassed around the separation chamber where they travel through the volute area before discharging through the outlet. Treated water moves through 2400-micron screen aperture openings, under the oil baffle and exits the system. The separation screen remains clog free due to continuous deflection. The CDS2015 used for testing consisted of a 5-ft diameter welded aluminum structure with a maximum depth of 4.17-ft between the floor of the sump and the invert of the inlet pipe. The 1 U.S. Silica Company, P.O. Box 187, Berkeley Springs, WV 25411; (800) 243-7500; www.u-s-silica.com environmental November 5, 2009 4 FB Environmental Associates, Inc diameter of the inlet and outlet pipes of the test system were 12-in and entered and exited the system as shown in Figure 3. As shown in Figure 3, the CDS test unit was tested using a recirculation system. Water is pumped through the test unit and into the catch tank. Water is recirculated directly from the 6.0ft x 12.0-ft x 3.0-ft (LxWxD) aluminum catch tank by a 10-hp submersible pump, directly back into the influent line, Figure 3. Flow was controlled by a calibrated butterfly valve placed on the influent line that was operated to produce a steady state flow condition. Flow was measured with an electromagnetic flow meter, Sea Metrics WMX-Series Industrial Magmeter. All piping consisted of schedule 40 PVC. OK-110 was injected as concentrated slurry downward into the influent pipe via a slurry injection port located 5-ft upstream of the test unit, and kept from recirculating within the test apparatus by filtering the effluent as it passed through the catch tank. The slurry injection system is detailed in Figure 4. Slurry was produced in a 1200-L conical bottom, polyethylene (PE) tank (Chem-Tainer). The conical bottom design ensured the continuous circulation of materials within the slurry tank. Suspension of solids within the slurry tank was maintained by a 1-hp, electric mixer with dual 5-in propellers (INDCO Model CL1-T). The propeller design maximized the vertical circulation of solids within the tank and ensured the homogeneity of the mixture. Four evenly spaced, vertically oriented baffles, measuring 42-in x 3.0-in x 0.5-in (LxWxThickness), affixed to the sidewalls of the slurry tank prevented mixer-induced vortexing. Figure 3: Diagram of the test facility, with flow pathways indicated by arrows. The CDS2015 unit. (Figure courtesy of Contech Construction Products, Inc.) environmental November 5, 2009 5 FB Environmental Associates, Inc Figure 4: Schematic diagram of the slurry injection system. Arrows indicate flow pathway. (Figure courtesy of Contech Construction Products, Inc.) A peristaltic pump (Randolph Austin) was used to inject slurry into the slurry injection port at a flow rate of 7 gpm to 15 gpm depending on desired sediment loading rate. The pump also served to circulate water through the underlying manifold of the slurry tank before injection so as to eliminate any possibility of sediment accumulation in the manifold. A one-inch, three-way ball valve was used to divert the slurry recirculating through the slurry tank manifold to the injection port via an injection manifold consisting of one-inch wire-reinforced PVC tubing and a vane- indicator flow meter (ERDCO See-Flow 3222-03T0). Influent samples were collected by reversing the ball valve to recirculate the slurry into a 500 ml sample bottle prior to injection, as seen in Figure 4. Effluent was sampled directly by sweeping a 500-mL sample bottle through the free discharge from the effluent pipe. Effluent from the CDS outlet pipe freely discharged into the catch tank and was pumped back to the influent line after passing through the filter bags. The effluent filter consisted of a plate containing eighteen 7-in dia. x 34-in long, 50-µm nominal-rated, polypropylene felt filter bags. Background samples were collected by dipping a 500 ml bottle into the furthest bay of the catch tank downstream from the filters. The operational procedure for removal efficiency testing consisted of performing multiple runoff simulations (sims). Prior to each sim, a new slurry solution was prepared by filling the drained and cleaned slurry tank with 1200-L of tap water, activating the pump and mixer, and adding the predetermined quantity of OK-110 material. Slurry was allowed to mix and recirculate in the environmental November 5, 2009 6 FB Environmental Associates, Inc slurry tank for several minutes before use. Each sim was begun by commencing influent and effluent return flows at a predetermined flow rate. After attaining a steady-state flow condition, slurry injection was started at a predetermined flow rate and the temperature of water in the test apparatus was measured. The system was then given 3 residence times to equilibrate before the first set of corresponding background, slurry, and effluent samples were taken at 1-min intervals until a total of six sets had been collected. Following the collection of the last set of performance assessment samples, slurry injection and flow to the test unit were stopped. The test unit was drained and emptied of captured sediment between simulations. Discrete influent, effluent, and background sample sets were collected for solids analysis. For this document, a set is defined as a collection of background, influent, and effluent sample pairs corresponding to a specific sim. Sample handling was performed in accordance with standard handling techniques. All samples to be tested for solids were promptly refrigerated and analyzed following collection. Maine Environmental Laboratory2 performed analysis according to ASTM method D3977—essentially a “whole sample” variation of EPA method 160.2. Re-suspension Testing The CDS2015 used for testing consisted of a 5-ft diameter welded aluminum structure with a maximum depth of 4.83-ft between the floor of the sump and the invert of the inlet pipe. The difference in sump depth between the removal efficiency testing and the re-suspension testing is due to the inclusion of an 8-in aluminum insert in the latter tests, to better simulate the concrete insert found in most field deployments. The diameter of the inlet and outlet pipes of the test system were 12-in, and entered and exited the system as shown in Figure 3. Re-suspension testing was conducted with a false floor installed into the sump to efficiently represent the 50% and 100% sediment storage capacity conditions. The false floor was constructed of plywood and supported by cement blocks. It was then sealed with plastic sheeting and waterproof tape. The floor was installed 3-in below the target sediment depth and 3-in of OK-110 material was loaded onto the floor to bring the top of the sediment pile to the appropriate elevation for each trial. For the CDS2015, the 50% sediment storage capacity is defined as 8.05 in. However in this case the “50%” resuspension trials were conducted with a sediment depth of 12.6-in (78% of capacity), with a distance of 45.44-in between the top of the sediment pile and the invert of the influent pipe. The 100% sediment storage capacity is defined as 16.1-in, with a distance of 41.9- in between the top of the sediment pile and the invert of the influent pipe. During re-suspension testing no sediment was injected into the unit and only background and effluent samples were collected. During each trial, flow was introduced and allowed to stabilize before sampling in one minute increments. A total of 6 effluent samples and 1 background sample were collected at each flow rate. Re-suspension tests began at the lowest target flow rate. 2 Maine Environmental Laboratory, 1 Main St, Yarmouth, ME 04096 environmental November 5, 2009 7 FB Environmental Associates, Inc Once sampling was complete, the flow rate was increased and the sampling process was repeated. This continued until the maximum flow rate was achieved. The operational procedure for re-suspension testing consisted of performing two runoff simulations (sims), one at sediment storage at 50% of capacity, the other at 100%. Each sim was begun by commencing effluent return flows at a predetermined flow rate. After attaining a steady-state flow condition using clean influent, flow rate and temperature of water in the test apparatus was measured. The system was then given 3 residence times to equilibrate before the first set of effluent and background samples were taken at 1-min intervals. After each set of six samples, the flow rate was increased and sampling was conducted again. The initial target flow rate was set at 0.1 cfs, and increasing through the following series: 0.28, 0.63, 0.88, 1.22, 1.47, 1.76, and 1.92 cfs. These flows correspond to the target flows of the removal efficiency testing. Actual measured flow rates are presented in Table 2. Following the collection of the last set of re-suspension samples, flow to the test unit was stopped. The test unit was drained, emptied, inspected, and refilled with OK-110 to the appropriate sediment storage capacity between simulations. Since the invert of the effluent pipe was several feet above the water surface elevation of the catch tank, effluent was sampled directly from the discharge of the effluent pipe. All sampling was conducted in the presence of an observer from FB Environmental. Results and Discussion Removal Efficiency Testing The testing plan was successfully carried out. All 21 test runs were completed, three at each of the seven stated treatment capacities, with results presented in Table 1. The results of the testing were inserted into the weighted NJDEP efficiency calculation assuming a 100% treatment rate of 1.4 cfs yielding a weighted removal efficiency estimate of 70% (Table 3). Measured flow rates were between 0.12 and 1.8 cfs, corresponding to between 9% and 129% of the treatment rate for the CDS 2015 using the weighted New Jersey Department of Environmental Protection (NJDEP) methodology to estimate performance. Influent concentration averaged 313 mg/L, compared to a target concentration of 300 mg/L. Reported influent and effluent values for each sim are averages of grab samples taken once per minute for six minutes immediately after the calculated detention time at the appropriate flow rate. Data integrity was very good. Six grab samples were taken of influent, effluent, and background TSS concentrations during each test run, for a total of 126 samples each, and a combined total of 378 grab samples. During the course of sampling, a total of five influent samples were considered outliers. No more than one grab sample per sample run was excluded, and a maximum of 2 out of 18 possible influent samples (over three test runs) were rejected for any given target treatment capacity. Dixon’s Q-test was used to confirm outlier status. Removal of these outliers resulted in a more conservative statement of removal efficiency, since their TSS figures were higher than the corrected average influent concentration in every case. Three effluent samples and three background samples were lost during processing (e.g., accidental environmental November 5, 2009 8 FB Environmental Associates, Inc spill). There were a total of 11 missing and excluded samples out of a possible 387, for an overall data completeness of 97%. Removal efficiencies were calculated by using the following equation: RE = ((influent solids concentration) – (effluent solids concentration)) / (influent solids concentration). Of the 123 background samples collected, 112 (91%) were below the limit of detection of 4 mg/L. Only 5 of the 21 test runs had any background samples with detectable TSS. The maximum concentration was 8 mg/L, and the highest average value for a test run was 6.5 mg/L. High background levels would indicate that the filter plate between the effluent and the intake for recycled clean water was leaking, and would lead to an underestimation of TSS removal efficiency. The data indicate this was not a significant problem during this product evaluation. Figure 5 shows a strong a linear relationship between flow rate and removal efficiency. The relationship is both strong (R2=0.975) and significant (p<0.001). Table 1: Observed performance of removal of OK-110 material by the CDS Model2015 under "maintained" conditions (sediment storage at 0% capacity). Actual Treatment Capacity (%) Measured Flow Rate (cfs) Influent Concentration TSS (mg/L) Effluent Concentration TSS (mg/L) Removal Efficiency 10 0.14 292 0 100% 9 0.12 303 0 100% 9 0.13 262 0 100% 21 0.3 305 11 97% 22 0.31 309 10 97% 22 0.31 309 12 96% 44 0.61 299 53 82% 40 0.56 333 51 85% 41 0.58 327 59 82% 66 0.93 303 128 58% 68 0.95 295 115 61% 66 0.92 294 120 59% 81 1.14 341 162 52% 84 1.18 298 153 49% 84 1.17 320 152 53% 105 1.47 323 194 40% 105 1.47 323 194 40% 105 1.47 324 202 38% 129 1.8 325 227 30% 125 1.75 326 231 29% 129 1.8 355 226 36% environmental November 5, 2009 9 FB Environmental Associates, Inc Table 2: Observed re-suspension performance of the CDS Model 2015 using influent with zero TSS, and sediment storage capacity at 50% and 100% of capacity. ND means below detection limit. Sediment Storage at 50% Capacity Sediment Storage at 100% Capacity Treatment Capacity (%) Average Influent Flow (cfs) Effluent Concentration TSS (mg/L) Treatment Capacity (%) Average Influent Flow (cfs) Effluent Concentration TSS (mg/L) 7 0.1 ND 9 0.12 ND 20 0.28 ND 20 0.28 ND 45 0.63 ND 42 0.59 ND 63 0.88 ND 63 0.88 ND 87 1.22 ND 85 1.19 ND 105 1.47 ND 104 1.46 ND 126 1.76 ND 125 1.75 ND 137 1.92 ND 136 1.91 7 Table 3. Annual CDS Removal Efficiency Estimate Using NJDEP Weighted Methodology Percent of Treatment Flow Target Flow (CFS) Avg CDS Flow* (CFS) Removal Efficiency* Weight Factor Weighted Removal 25% 0.35 0.31 97% 0.25 24% 50% 0.7 0.58 83% 0.3 25% 75% 1.05 0.93 59% 0.2 12% 100% 1.4 1.47 39% 0.15 6% 125% 1.75 1.78 32% 0.1 3% *Average of 3 test runs 70% Re-suspension Testing The results of re-suspension testing at 50% and 100% of the sediment storage capacity are shown in Table 2. As seen in Table 2, at 50% sediment storage capacity, effluent concentration remained at or below the limit of analytical detection (4 mg/L) across the range of flows from 0.09 cfs to 1.92 cfs. At 100% sediment storage capacity, effluent concentration was below the limit of detection for flow of 0.12 cfs to 1.75 cfs. Only at 1.91 cfs (corresponding to 136% of the design capacity) was there detectable TSS, averaging 7 mg/L. Background sediment concentrations were below the limit of detection throughout both re-suspension trials and were not used to adjust effluent concentrations. environmental November 5, 2009 10 FB Environmental Associates, Inc y = -0.4463x + 1.0646 R2 = 0.9749 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0.00.20.40.60.81.01.21.41.61.82.0 Flow Rate (cfs) Re m o v a l E f f i e c i n c y ( % ) Figure 5: Observed TSS removal efficiency of the CDS2015 under “maintained” conditions (sediment storage at 0% of capacity) using OK-110 silica. Conclusion Removal Efficiency Testing This study successfully measured CDS Model 2015 performance at influent flows from 0.12- 1.8 cfs, with influent TSS concentrations in the range of 300 mg/L. A strong and highly significant linear relationship between flow and removal efficiency was demonstrated. Removal efficiency ranged from 100% to approximately 30% across tested conditions, as shown in Figure 5. Re-suspension Testing The re-suspension test indicated that there is no observable re-suspension of TSS with the sediment storage capacity at 50% and 100% of capacity, except for a small amount (7 mg/L TSS) at very high flows (137% of design capacity) when the sediment storage sump was 100% full. A representative from FB Environmental, an independent, third-party reviewer, observed every sample run, as indicated in Table 3. Original data files from Maine Environmental Laboratory and subsequent spreadsheets and calculations were examined as well. FB Environmental reviewed sample plans, verified measurements, witnessed all sample collections, checked data against signed laboratory analysis reports, and performed the statistical analysis presented in this report. The data collected meets a high standard for completeness, and the results are deemed to accurately represent the total suspended solids removal efficiency and storage of the CDS2015 under the stated conditions. environmental November 5, 2009 11 FB Environmental Associates, Inc Table 4: Testing schedule, lab analysis date, and reviewer. Date Sampled Date Lab Tests Test3 Test Run FB Environmental Reviewer 7/20/2009 8/5/2009 CDS 125 1 Fred Dillon 7/27/2009 7/31/2009 CDS 125 2 Fred Dillon 7/28/2009 8/3/2009 CDS 125 3 Fred Dillon 7/30/2009 8/6/2009 CDS 100 1 Fred Dillon 7/31/2009 8/6/2009 CDS 100 2 Fred Dillon 8/3/2009 8/12/2009 CDS 100 3 Fred Dillon 8/4/2009 8/12/2009 CDS 75 1 Fred Dillon 8/6/2009 8/13/2009 CDS 75 2 Fred Dillon 8/7/2009 8/13/2009 CDS 75 3 Fred Dillon 8/10/2009 8/26/2009 CDS 50 1 Cayce Dalton 8/11/2009 8/26/2009 CDS 50 2 Forrest Bell 8/13/2009 8/26/2009 CDS 50 3 Cayce Dalton 8/13/2009 8/31/2009 CDS 25 1 Cayce Dalton 8/14/2009 8/31/2009 CDS 25 2 Forrest Bell 8/17/2009 9/1/2009 CDS 25 3 Cayce Dalton 8/18/2009 9/1/2009 CDS 10 1 Forrest Bell 8/19/2009 9/3/2009 CDS 10 2 Cayce Dalton 8/20/2009 9/3/2009 CDS 10 3 Cayce Dalton 9/2/2009 9/15/2009 CDS 150 1 Cayce Dalton 9/3/2009 9/15/2009 CDS 150 2 Cayce Dalton 9/4/2009 9/17/2009 CDS 150 3 Forrest Bell 9/28/2009 10/9/2009 CDS 50 washout 1 Cayce Dalton 10/20/2009 10/26/2009 CDS 100 washout 1 Cayce Dalton 3 Test refers to unit (CDS 2015) together with the identifier used during laboratory analyses. These identifiers are incremental, so that CDS 10 refers to test runs targeting 10% of design capacity. Note that identifiers do not exactly match the actual percent of design capacity tested. Washout refers to re-suspension testing. environmental November 5, 2009 12 FB Environmental Associates, Inc environmental November 5, 2009 13 FB Environmental Associates, Inc I have reviewed and approve this report, entitled “Independent Review of CD2015 Product Evaluation.” November 5, 2009 Date Principal of FB Environmental 97A Exchange St., Portland ME Design Ratio1 = Rainfall Intensity Flow Rate Operating Rate2 % Total Rainfall Rmvl. Effcy4 Rel. Effcy "/hrcfs cfs/ft3 Depth3 (%)(%) 0.020.000.0000410.2%98.0%10.0% 0.040.000.000089.6%98.0%9.5% 0.060.000.000129.4%98.0%9.3% 0.080.000.000167.7%98.0%7.6% 0.100.010.000208.6%98.0%8.4% 0.120.010.000246.3%98.0%6.2% 0.140.010.000294.7%98.0%4.6% 0.160.010.000334.6%98.0%4.5% 0.180.010.000373.5%98.0%3.5% 0.200.010.000414.3%98.0%4.3% 0.250.010.000518.0%98.0%7.8% 0.300.020.000615.6%98.0%5.5% 0.350.020.000714.4%98.0%4.3% 0.400.020.000812.5%98.0%2.5% 0.450.020.000922.5%98.0%2.5% 0.500.030.001021.4%98.0%1.4% 0.750.040.001535.0%98.0%4.9% 1.000.050.002041.0%98.0%1.0% 1.500.080.003060.0%98.0%0.0% 2.000.110.004070.0%98.0%0.0% 3.000.160.006110.5%98.0%0.5% 98.0% 0.0% 6.5% 91.5% 1 - Design Ratio = (Total Drainage Area x Runoff Coefficient) / VortSentry HS Treatment Volume = The Total Drainage Area and Runoff Coefficient are specified by the site engineer. 2 - Operating Rate (cfs/ft3) = Rainfall Intensity ("/hr) x Design Ratio 3 - Based on 10 years of hourly precipitation data from NCDC Station 770, Boston WSFO AP, Suffolk County, MA Calculated by: CJA Date:02/04/15Checked by:Date: System VSHS36 (ALT TO CDS2015-4) = 0.0020.06 acres x 0.9 27 ft3 VortSentry® HS Estimated Net Annual TSS Reduction ADDITION TO ROCKRIDGE RETIREMENT FACILITY NORTHAMPTON, MA Model VSHS36 Based on an Average Particle Size of 240 Microns % rain falling at >0''/hr = Removal Efficiency Adjustment4 = 4 - Reduction due to use of 60-minute data for a site that has a time of concentration less than 30-minutes. Predicted Net Annual Load Removal Efficiency = VortSentry® HS Performance Testing With OK-110 Prepared by: Heather Tetreault Introduction The VortSentry® HS (VSHS) model HS48 is an offline treatment chamber that allows for the settling of solids and separation of free oil and grease commonly found in stormwater runoff. Figure 1 details a typical VSHS unit. The performance characteristics and the scour potential of the HS48 were assessed under controlled, laboratory conditions using OK-110 silica sand. Figure 1: Schematic of a typical VortSentry HS. Scope All testing has been conducted in compliance with the requirements specified in the NJDEP’s “Total Suspended Solids Laboratory Testing Procedure”. Three primary testing objectives are bulleted below: · Objective 1. Identify the target treatment flow rate. A series of full scale preliminary tests will be conducted in CONTECH’s laboratory in order to accurately identify an appropriate target treatment flow rate for the VortSentry HS model HS48. · Objective 2. Conduct two tests at the maximum hydraulic operating rate for the laboratory model HS48. The tests will be conducted at 50 and 100 percent of the unit’s sediment capture capacity respectively. The sediment capacity in the test unit was accomplished by constructing a false floor. Tests will be conducted with clean water to determine the potential for solids resuspension and washout. · Objective 3. Conduct a minimum of 15 test runs. Three tests each at a constant flow rate of 25, 50, 75, 100, and 125 percent of the treatment flow rate. These tests will be conducted with an initial sediment loading of 50% of the unit’s capture capacity. Testing Procedure Contaminant A commercial sand product, OK-110 silica sand, was used as the surrogate pollutant for this test series. This product is manufactured by the US Silica Company, and the materials used for testing originated from the Mill Creek, OK plant. OK-110 is a natural silica sand product (SG=2.65) consisting of unground sand that has been processed to produce a distribution of particles between 50-um and 200-um with a d50 of approximately 105-um (Figure 2). Figure 2: Particle size distribution of OK-110 based upon manufacturer specifications (U.S. Silica, ND) Test Apparatus A VSHS model HS48 was used for all testing reported herein. The test unit is a 4-ft diameter, welded aluminum structure with a maximum depth of 6.5-ft between the floor of the treatment chamber and the invert of the inlet pipe when false floor is not present. The diameter of the inlet and outlet pipes of the test unit were 12-inches and the pipes entered and exited the test system as shown in Figure 1. An internal bypass weir diverts the water quality flow to the treatment chamber and is set at 11-inches. The model HS48 test unit was tested using a recirculation system. Water is pumped through the test unit and into the catch tank. Water is recirculated directly from the 6.0-ft x 12.0-ft x 3.0-ft (LxWxD) aluminum catch tank by a10-hp submersible pump, directly back into the influent line, Figure 3. Flow was controlled by a calibrated butterfly valve placed on the influent line that was operated to produce a steady-state flow condition. Flow was measured with an electromagnetic flow meter, Sea Metrics WMX-Series Industrial Magmeter. All piping consists of schedule 40 PVC. Figure 3: Schematic of laboratory set up. OK-110 was injected as concentrated slurry downward into the influent pipe via a slurry injection port located 5-ft upstream of the test unit, and kept from recirculating within the test apparatus by filtering the effluent as it passed through the catch tank. The slurry injection system is detailed in Figure 4. Slurry was produced in a 1200-L conical bottom, polyethylene (PE) tank (Chem- Tainer). The conical bottom design ensured the continuous circulation of materials within the slurry tank. Suspension of solids within the slurry tank was maintained by a 1-hp, electric, mixer with dual 5- in propellers (INDCO Model CL1-T). The propeller design maximized the vertical circulation of solids within the tank and ensured the homogeneity of the mixture. Four, evenly spaced, vertically oriented baffles, measuring 42-in x 3.0-in x 0.5-in (LxWxThickness), affixed to the sidewalls of the slurry tank prevented mixer-induced vortexing. A peristaltic pump (Randolph Austin) was used to inject slurry into the slurry injection port at a flow rate of 10 gpm to 15 gpm. The pump also served to circulate water through the underlying manifold of the slurry tank before injection so as to eliminate any possibility of sediment accumulation in the manifold. A one-inch, three-way ball valve was used to divert the slurry recirculating through the slurry tank manifold to the injection port via an injection manifold consisting of one inch wire- reinforced PVC tubing and a vane-indicator flow meter (ERDCO See-Flow 3222-03T0). Influent samples were collected by reversing the ball valve to recirculate the slurry into a 500 ml sample bottle prior to injection, as seen in figure 4. Effluent was sampled directly by sweeping a 500-mL sample bottle through the free discharge from the effluent pipe. Effluent from the model HS48 outlet pipe freely discharged into the catch tank and was pumped back to the influent line after passing through the filter bags. The effluent filter consisted of a plate containing eighteen 7-in dia. x 34-in long, 50-um nominal- rated, polypropylene felt filter bags. Background samples were collected by dipping a 500 ml bottle into the furthest bay of the catch tank downstream from the filters. Figure 4. Schematic diagram of the slurry injection system. Arrows indicate flow pathways. Operation Washout Evaluation Washout testing was conducted with a false floor installed in the sump to mimic the 50% and 100% sediment storage capacity conditions. For the HS48, 50% sediment storage is 6-inches reducing the depth below the pipe invert to 72-inches (6 feet). The 100% sediment storage capacity is 12-inches, reducing the depth below invert to 66-inches (5.5 feet). The false floor was constructed using cement blocks, ply wood and sealed with a plastic liner attached to the side walls of the test unit. The false floor was installed 3-inches below the target sediment depth and 3-inches of OK-110 material was loaded onto the floor to bring the top of the sediment pile to the appropriate elevation for each trial. After loading the sediment and filling the system, flow was introduced and slowly increased to full hydraulic capacity allowing the sediment to form into a pile representative of field conditions. During washout testing no sediment was injected into the unit and only background and effluent samples were collected. During each trial flow is introduced and allowed to stabilize before sampling in one minute increments. A total of 6 background and 6 effluent samples were collected at each flow rate. Washout sims began at the lowest target flow rate. Once sampling is complete the flow rate was increased, and after allowing three minutes for flow to re-stabilize, the process was repeated. This continued until hydraulic capacity was reached. Removal Efficiency Evaluation The operational procedure for performance evaluation consisted of performing 15 runoff simulations (sims). Prior to each sim, a new slurry solution was prepared by filling the drained and cleaned slurry tank with 1200-L of water, activating the pump and mixer, and adding the pre-determined quantity of OK-110 material. Slurry was allowed to mix and recirculate in the slurry tank for several minutes before use. Each sim began by introducing flow to the system and stabilizing the flow at a predetermined flow rate, see Table 1. After attaining a steady- state flow condition, slurry injection was started at a predetermined rate based on target influent concentration. The system was allowed to operate for three residence times before the first set of corresponding background, slurry, and effluent samples were taken. All samples were taken in 1-min intervals until a total of six sets had been collected. Flow rate was recorded in 1-min intervals until sim completion. Following the collection of the last set of performance assessment samples, slurry injection and flow to the test unit were stopped. Testing was conducted by using a top down approach, beginning with the 125% of treatment flow sims and then working down through the sims to the 25% of treatment flow sims. The test unit was not cleaned out and reset between sims. Sampling Background samples were collected in the last bay of the catch tank, downstream of the filter plate, by dipping a 500 ml sample bottle into the pooled water in the tank. Influent samples were taken in the slurry tank by filling the sample bottle from the freely discharging return line. Influent concentrations were then calculated using the slurry concentration, known slurry injection rate, and known influent flow rate. Since the invert of the effluent pipe was several feet above the water surface elevation of the catch tank, effluent was sampled directly from the discharge of the effluent pipe by sweeping a 500-mL sample bottle through the pipe discharge. Sample Analysis Influent, effluent, and background sample sets were collected for solids analysis. Sample analysis was performed in-house. A set is defined as a collection of background, influent, and effluent sample pairs corresponding to a specific sim. All samples were analyzed within five days of collection. A trained CONTECH Technician performed analysis according to ASTM method D3977 SSC—a “whole- sample” variation of EPA method 160.2 TSS. Effluent and background samples where composited with a 4-L Bel-Art 37805 Series Churn Sample Splitter to reduce the number of samples required to be processed from six to one 500 ml composite sample for the effluent and background respectively. Influent slurry samples were not composited due to concentrations in excess of 1000 mg/L. Previous trials have shown that the churn splitter does not produce a representative composite sample when solids concentrations are very high. Removal efficiencies were calculated by using the average influent solids concentration and the composite effluent solids concentration corresponding to a sim and applying the following standard formula: ((influent solids conc.) – (effluent solids conc.)) / (influent solids conc.). Results/Discussion Washout The results of washout testing at 50% and 100% of sediment storage capacity are shown in Table 1. During the 50% sediment capacity sim, a Sea Metric Magmeter flow meter measured flow rates and the corresponding water surface elevation levels (WSEL) were also recorded. Washout testing at 100% sediment capacity was conducted without the use of the Magmeter. Water surface elevation levels were measured in the influent bay of the HS48’s trough throughout the duration of the 50 % and100% sediment storage sims. The 50% flow vs. WSEL data was plotted and the corresponding linear regression formula was used to calculate the flow rates for the 100% sediment loading sim. Three separate sims were conducted at 100% sediment capacity. Water Surface Elevation Level y = 11.79x + 0.2963 R2 = 0.9939 y = 4.6965x + 5.5331 R2 = 0.9983 0.000 2.000 4.000 6.000 8.000 10.000 12.000 14.000 16.000 0.000.501.001.502.00 Q (cfs) WS E L ( i n ) No Bypass Bypass Linear (No Bypass) Linear (Bypass) Figure 5: Plot of water surface elevation levels (WSEL) taken in the first bay of the trough of the model HS48 and the corresponding flow rates. Formulas are calculated based on WSEL with and without bypass. Some residual fine materials are expected in the effluent during washout trials of this nature. Since 20 mg/l is often cited as an irreducible concentration it is used as the washout threshold. At 50% of sediment storage capacity, effluent concentrations >20 mg/L occurred between 1.12 and 1.62 cfs, which exceeds the 125% of treatment flow rate of 0.84cfs. The collection method varied from the 50% to the 100% sediment capacity sims, which may have impacted the results during the 100% test. Observations and data appear to show that stopping and starting the system, resulting in 3 sims at varying flow rates produced lower sediment concentrations at the start of sims 2 and 3 than would have been expected during a single continuous sim. At 100% of No Bypass Bypass sediment storage capacity effluent concentrations >20 mg/L occurred during the first sim at a flow rate of 0.51 cfs. This exceeds the washout threshold and makes sims two and three inconsequential. At the conclusion of the 100% sim the system was drained revealing that a significant mass of sediment remained in the sump of the test unit. Background sediment concentrations were low throughout all washout trials and were not used to adjust effluent concentrations. Average background concentrations during the 50% sim were < 2mg/L and < 4 mg/L during the 100% sims. . 50%-6" Washout Sim 100%-12" Washout Sim Q (cfs) SIM Effluent Concentration (mg/L) Q (cfs)- Calculated SIM Effluent Concentration (mg/L) 0.19 1 1.98 0.312 1 3.82 0.41 1 12.47 0.51 1 20.2 0.62 1 4.13 0.77 1 36.06 0.77 1 12.45 1.03 2 10.71 1.12 1 8.55 1.34 2 14.58 1.62 1 33.06 1.60 2 15.94 1.94 1 40.82 1.68 2 20.79 1.77 3 12.96 2.05 3 22.93 2.52 3 24.27 Table 1: Effluent concentrations for VortSentry HS48 washout testing at 50% and 100% of sediment storage capacity. Removal Efficiency at 50% Sediment Capacity A total of 15 simulations were performed at flow rates between 0.17 and 0.84 cfs with varying influent concentrations ranging from 92-359 mg/L. The results of each performance trial are shown in Table 2. In general as flow rate increased, removal efficiency tended to decrease. This relationship is consistent with past performance evaluations of the VSHS, and does not come as a surprise since the effectiveness of a flow through device is largely governed by hydraulic loading rate. Background solids concentrations were not used to adjust the results of any performance trials since background concentrations were negligible throughout. HS48 Performance Evaluation at 50% Sediment Storage Capacity Percent of Treatment Flow Target Q (cfs) Average Q (cfs) Average Influent Concentration (mg/L) Average Effluent Concentration (mg/L) % RE 0.17 299 12.25 95.9 0.16 205 13.92 93.2 25% 0.175 0.17 105 2.11 97.9 0.33 359 88.69 75.3 0.33 237 77.09 67.5 50% 0.35 0.31 92 39.45 70.8 0.51 359 146.8 59 0.48 221 75.4 65.9 75% 0.525 0.5 118 66.09 43.8 0.64 329 126.73 61.5 0.65 253 74.53 60.1 100% 0.7 0.63 135 53.72 70.5 0.88 315.6 152.72 51.6 0.83 229.9 182.4 20.7 125% 0.875 0.82 128 86.32 32.6 Table 2. Results of VortSentry HS48 removal efficiency testing with OK-110 at 50% of sediment storage capacity. The New Jersey Department of Environmental Protection (NJDEP) developed a weighted formula to estimate the performance of flow through separators over a typical rainfall year (based on NJ rainfall). The results of 3 trials at each target flow rate are averaged and then multiplied by a weight factor. The sum of the 5 weighted removal factors represents the estimated effectiveness of the device during a given rainfall year. Analysis of the 15 simulations (Table 3) indicates that the tested configuration of the VortSentry HS48 achieved a weighted solids removal (OK-110) of 69.6% at a water quality flow of 0.64cfs. Percent of Treatment Flow Actual Model HS48 flow Removal Efficiency (%) Weight Factor Weighted Removal (%) 25% 0.17 96 0.25 23.9 50% 0.32 71 0.3 21.4 75% 0.50 56 0.2 11.2 100% 0.64 64 0.15 9.6 125% 0.84 35 0.1 3.5 69.6 Table 3: Weighted results of VortSentry HS48 OK-110 performance trials using the NJDEP performance calculation. Flow and removal efficiency for each percentage of treatment flow are the average of 3 trials. It is important to emphasize that these conclusions reflect laboratory-based testing performed under controlled conditions. Field conditions are variable with regard to solids characteristics and sampling methods, and comparison of this experiment to field derived data will be accordingly affected. Section 5 Soil Data DE P F o r m 1 1 S o i l S u i t a b i l i t y A s s e s s m e n t f o r O n - S i t e S e w a g e D i s p o s a l • P a g e 3 o f 7 Co m m o n w e a l t h o f M a s s a c h u s e t t s Ci t y / T o w n o f Fo r m 1 1 - S o i l S u i t a b i l i t y A s s e s s m e n t f o r O n - S i t e S e w a g e D i s p o s a l i n c h e s e l e v a t i o n De e p O b s e r v a t i o n H o l e N u m b e r : _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Re d o x i m o r p h i c F e a t u r e s (m o t t l e s ) Co a r s e F r a g m e n t s % b y V o l u m e De p t h (I n . ) So i l Ho r i z o n / La y e r So i l M a t r i x : Co l o r - M o i s t (M u n s e l l ) De p t h C o l o r P e r c e n t So i l Te x t u r e (U S D A ) Gr a v e l C o b b l e s & S t o n e s So i l S t r u c t u r e S o i l Co n s i s t e n c e (M o i s t ) Ot h e r Ad d i t i o n a l N o t e s _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 0- 6 Ap 10 Y R 3 / 3 -- -- -- Lo a m y s a n d -- - 0% Gr a n u l a r Fr i a b l e Ro o t s 6- 2 8 Bw 10 Y R 5 / 6 -- -- - - Me d i u m sa n d 20 % <2 % Si n g l e G r a i n Lo o s e Ro o t s 28 + C* 5Y R 6 / 3 -- -- - - Me d i u m sa n d 5% 0 % Si n g l e G r a i n L o o s e F e w R o o t s Col e s M e a d o w R d # 1 No G W i n h o l e , N o m o t t l e s , N o s u r f a c e s t o n e s , H o l e 1 2 0 " d e e p * La y e r s o f f i n e a n d m e d i u m s a n d DE P F o r m 1 1 S o i l S u i t a b i l i t y A s s e s s m e n t f o r O n - S i t e S e w a g e D i s p o s a l • P a g e 5 o f 7 Co m m o n w e a l t h o f M a s s a c h u s e t t s Ci t y / T o w n o f Fo r m 1 1 - S o i l S u i t a b i l i t y A s s e s s m e n t f o r O n - S i t e S e w a g e D i s p o s a l De e p O b s e r v a t i o n H o l e N u m b e r : _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Re d o x i m o r p h i c F e a t u r e s (m o t t l e s ) Co a r s e F r a g m e n t s % b y V o l u m e De p t h (I n . ) So i l Ho r i z o n / La y e r So i l M a t r i x : Co l o r - M o i s t (M u n s e l l ) De p t h C o l o r P e r c e n t So i l Te x t u r e (U S D A ) Gr a v e l C o b b l e s & S t o n e s So i l St r u c t u r e So i l Co n s i s t e n c e (M o i s t ) Ot h e r Ad d i t i o n a l N o t e s _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ Col e s M e a d o w R d # 2 0- 6 Ap 10 Y R 3 / 3 -- -- -- Lo a m y S a n d -- - - Gr a n u l a r F r i a b l e R o o t s 6- 3 6 Bw 10 Y R 5 / 6 -- -- -- Me d i u m Sa n d 20 % < 2 % Si n g l e Gr a i n Lo o s e 36 + C 5Y R 6 / 3 -- -- -- Me d i u m Sa n d 5% 0 % Si n g l e Gr a i n Lo o s e Hol e 1 2 0 " D e e p , N o G W i n h o l e , N o s u r f a c e s t o n e s , N o m o t t l e s DE P F o r m 1 1 S o i l S u i t a b i l i t y A s s e s s m e n t f o r O n - S i t e S e w a g e D i s p o s a l • P a g e 5 o f 7 Co m m o n w e a l t h o f M a s s a c h u s e t t s Ci t y / T o w n o f Fo r m 1 1 - S o i l S u i t a b i l i t y A s s e s s m e n t f o r O n - S i t e S e w a g e D i s p o s a l De e p O b s e r v a t i o n H o l e N u m b e r : _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Re d o x i m o r p h i c F e a t u r e s (m o t t l e s ) Co a r s e F r a g m e n t s % b y V o l u m e De p t h (I n . ) So i l Ho r i z o n / La y e r So i l M a t r i x : Co l o r - M o i s t (M u n s e l l ) De p t h C o l o r P e r c e n t So i l Te x t u r e (U S D A ) Gr a v e l C o b b l e s & S t o n e s So i l St r u c t u r e So i l Co n s i s t e n c e (M o i s t ) Ot h e r Ad d i t i o n a l N o t e s _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ Col e s M e a d o w R d # 3 0- 6 Ap 10 Y R 3 / 3 -- -- -- Lo a m y S a n d -- - - Gr a n u l a r Fr i a b l e Ro o t s 6- 3 3 Bw 10 Y R 5 / 6 -- -- -- Lo a m y S a n d 30 % < 2 % Su b a n g u l a r Bl o c k y Fr i a b l e 33 + C* 10 Y R 6 / 2 5Y R 6 / 2 -- -- -- Lo a m y F i n e Sa n d -- -- Ma s s i v e V e r y F r i a b l e Hol e 1 2 0 " D e e p , N o G W i n h o l e , F e w s u r f a c e s t o n e s , M o t t l e s b e t w e e n l a y e r s o f f i n e s a n d a n d l o a m y f i n e s a n d i n C * La y e r s o f f i n e s a n d a n d l o a m y f i n e s a n d t5form12.doc• 06/03 Perc Test • Page 1 of 1 Commonwealth of Massachusetts City/Town of Percolation Test Form 12 Percolation test results must be submitted with the Soil Suitability Assessment for On-site Sewage Disposal. DEP has provided this form for use by local Boards of Health. Other forms may be used, but the information must be substantially the same as that provided here. Before using this form, check with the local Board of Health to determine the form they use. A. Site Information Owner Name Street Address or Lot # City/Town State Zip Code Contact Person (if different from Owner) Telephone Number Important: When filling out forms on the computer, use only the tab key to move your cursor - do not use the return key. B. Test Results Date Time Date Time Observation Hole # Depth of Perc Start Pre-Soak End Pre-Soak Time at 12” Time at 9” Time at 6” Time (9”-6”) Rate (Min./Inch) Test Passed: Test Failed: Test Passed: Test Failed: Test Performed By: Witnessed By: Comments: Rockridge 27ColesmeadowRoad NorthamptonMa 7-10-078:50 3 8:55 9:02 9:09 ~2min./inch BenMessersmithC&C DanMorenoC&C Percholes1&2didnotholdwater,sandycomposition United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Hampshire County, Massachusetts, Central Part Rockridge Retirement Facility Natural Resources Conservation Service January 5, 2015 8 Custom Soil Resource Report Soil Map 46 9 1 8 2 0 46 9 1 8 6 0 46 9 1 9 0 0 46 9 1 9 4 0 46 9 1 9 8 0 46 9 2 0 2 0 46 9 2 0 6 0 46 9 2 1 0 0 46 9 2 1 4 0 46 9 1 8 2 0 46 9 1 8 6 0 46 9 1 9 0 0 46 9 1 9 4 0 46 9 1 9 8 0 46 9 2 0 2 0 46 9 2 0 6 0 46 9 2 1 0 0 46 9 2 1 4 0 694170 694210 694250 694290 694330 694370 694410 694170 694210 694250 694290 694330 694370 694410 42° 21' 26'' N 72 ° 3 8 ' 3 2 ' ' W 42° 21' 26'' N 72 ° 3 8 ' 2 1 ' ' W 42° 21' 15'' N 72 ° 3 8 ' 3 2 ' ' W 42° 21' 15'' N 72 ° 3 8 ' 2 1 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 050100200300Feet 02550100150Meters Map Scale: 1:1,700 if printed on A portrait (8.5" x 11") sheet. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Hampshire County, Massachusetts, Central Part Survey Area Data: Version 9, Sep 19, 2014 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Mar 28, 2011—May 12, 2011 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 9 Map Unit Legend Hampshire County, Massachusetts, Central Part (MA609) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 253A Hinckley loamy sand, 0 to 3 percent slopes 2.8 34.6% 711C Charlton-Rock outcrop-Hollis complex, sloping 5.3 65.4% 741A Amostown-Windsor silty substratum-Urban land complex, 0 to 3 percent slopes 0.0 0.1% Totals for Area of Interest 8.1 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that Custom Soil Resource Report 10 have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha- Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 11 Hampshire County, Massachusetts, Central Part 253A—Hinckley loamy sand, 0 to 3 percent slopes Map Unit Setting National map unit symbol: 9b06 Elevation: 0 to 1,000 feet Mean annual precipitation: 40 to 50 inches Mean annual air temperature: 45 to 52 degrees F Frost-free period: 140 to 240 days Farmland classification: Farmland of statewide importance Map Unit Composition Hinckley and similar soils: 80 percent Minor components: 20 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Hinckley Setting Landform: Outwash plains Landform position (two-dimensional): Footslope Landform position (three-dimensional): Tread Down-slope shape: Convex Across-slope shape: Convex Parent material: Loose sandy and gravelly glaciofluvial deposits Typical profile H1 - 0 to 8 inches: loamy sand H2 - 8 to 13 inches: loamy sand H3 - 13 to 29 inches: gravelly sand H4 - 29 to 60 inches: Error Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Excessively drained Runoff class: Very low Capacity of the most limiting layer to transmit water (Ksat): High to very high (6.00 to 20.00 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Low (about 3.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3s Hydrologic Soil Group: A Minor Components Windsor Percent of map unit: 10 percent Custom Soil Resource Report 12 Sudbury Percent of map unit: 10 percent 711C—Charlton-Rock outcrop-Hollis complex, sloping Map Unit Setting National map unit symbol: 99zm Mean annual precipitation: 40 to 50 inches Mean annual air temperature: 45 to 52 degrees F Frost-free period: 120 to 240 days Farmland classification: Not prime farmland Map Unit Composition Charlton and similar soils: 35 percent Rock outcrop: 25 percent Hollis and similar soils: 20 percent Minor components: 20 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Charlton Setting Landform: Hills Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down-slope shape: Linear Across-slope shape: Convex Parent material: Friable loamy eolian deposits over friable loamy basal till derived from granite and gneiss Typical profile H1 - 0 to 7 inches: fine sandy loam H2 - 7 to 13 inches: fine sandy loam H3 - 13 to 22 inches: gravelly fine sandy loam H4 - 22 to 60 inches: gravelly sandy loam Properties and qualities Slope: 8 to 15 percent Percent of area covered with surface fragments: 2.0 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.60 to 6.00 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Moderate (about 7.5 inches) Custom Soil Resource Report 13 Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7s Hydrologic Soil Group: A Description of Rock Outcrop Setting Parent material: Granite and gneiss Properties and qualities Slope: 0 to 15 percent Depth to restrictive feature: 0 inches to lithic bedrock Runoff class: Very high Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8s Description of Hollis Setting Landform: Hills Landform position (two-dimensional): Summit Landform position (three-dimensional): Side slope Down-slope shape: Linear Across-slope shape: Convex Parent material: Friable loamy basal till over granite and gneiss Typical profile H1 - 0 to 5 inches: fine sandy loam H2 - 5 to 19 inches: fine sandy loam H3 - 19 to 23 inches: bedrock Properties and qualities Slope: 8 to 15 percent Percent of area covered with surface fragments: 2.0 percent Depth to restrictive feature: 10 to 20 inches to lithic bedrock Natural drainage class: Well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Very low to low (0.00 to 0.01 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Very low (about 2.3 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7s Hydrologic Soil Group: D Minor Components Ridgebury Percent of map unit: 10 percent Landform: Depressions Custom Soil Resource Report 14 Chatfield Percent of map unit: 5 percent Woodbridge Percent of map unit: 5 percent 741A—Amostown-Windsor silty substratum-Urban land complex, 0 to 3 percent slopes Map Unit Setting National map unit symbol: 99z2 Mean annual precipitation: 40 to 50 inches Mean annual air temperature: 45 to 52 degrees F Frost-free period: 120 to 240 days Farmland classification: Not prime farmland Map Unit Composition Amostown and similar soils: 35 percent Urban land: 25 percent Windsor, silty substratum, and similar soils: 25 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Amostown Setting Landform: Terraces, outwash plains, deltas Landform position (two-dimensional): Summit, footslope Landform position (three-dimensional): Tread Down-slope shape: Convex Across-slope shape: Convex Parent material: Friable sandy glaciofluvial deposits over silty glaciolacustrine deposits Typical profile H1 - 0 to 7 inches: fine sandy loam H2 - 7 to 32 inches: fine sandy loam H3 - 32 to 60 inches: stratified very fine sand to silt loam Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Moderately well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat): Moderately low to moderately high (0.06 to 0.60 in/hr) Depth to water table: About 18 to 36 inches Frequency of flooding: None Custom Soil Resource Report 15 Frequency of ponding: None Available water storage in profile: High (about 9.3 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2w Hydrologic Soil Group: B Description of Windsor, Silty Substratum Setting Landform: Outwash plains Landform position (two-dimensional): Footslope Landform position (three-dimensional): Tread Down-slope shape: Convex Across-slope shape: Convex Parent material: Loose sandy glaciofluvial deposits over silty glaciolacustrine deposits Typical profile H1 - 0 to 8 inches: loamy sand H2 - 8 to 21 inches: loamy sand H3 - 21 to 45 inches: sand H4 - 45 to 60 inches: silt loam Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Somewhat excessively drained Runoff class: Very low Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.60 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Low (about 5.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3s Hydrologic Soil Group: A Minor Components Enosburg Percent of map unit: 10 percent Landform: Terraces Maybid Percent of map unit: 5 percent Landform: Depressions Custom Soil Resource Report 16 25 Custom Soil Resource Report Map—Hydrologic Soil Group (Rockridge Retirement Facility) 46 9 1 8 2 0 46 9 1 8 6 0 46 9 1 9 0 0 46 9 1 9 4 0 46 9 1 9 8 0 46 9 2 0 2 0 46 9 2 0 6 0 46 9 2 1 0 0 46 9 2 1 4 0 46 9 1 8 2 0 46 9 1 8 6 0 46 9 1 9 0 0 46 9 1 9 4 0 46 9 1 9 8 0 46 9 2 0 2 0 46 9 2 0 6 0 46 9 2 1 0 0 46 9 2 1 4 0 694170 694210 694250 694290 694330 694370 694410 694170 694210 694250 694290 694330 694370 694410 42° 21' 26'' N 72 ° 3 8 ' 3 2 ' ' W 42° 21' 26'' N 72 ° 3 8 ' 2 1 ' ' W 42° 21' 15'' N 72 ° 3 8 ' 3 2 ' ' W 42° 21' 15'' N 72 ° 3 8 ' 2 1 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 050100200300Feet 02550100150Meters Map Scale: 1:1,700 if printed on A portrait (8.5" x 11") sheet. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Hampshire County, Massachusetts, Central Part Survey Area Data: Version 9, Sep 19, 2014 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Mar 28, 2011—May 12, 2011 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 26 Table—Hydrologic Soil Group (Rockridge Retirement Facility) Hydrologic Soil Group— Summary by Map Unit — Hampshire County, Massachusetts, Central Part (MA609) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 253A Hinckley loamy sand, 0 to 3 percent slopes A 2.8 34.6% 711C Charlton-Rock outcrop- Hollis complex, sloping 5.3 65.4% 741A Amostown-Windsor silty substratum-Urban land complex, 0 to 3 percent slopes 0.0 0.1% Totals for Area of Interest 8.1 100.0% Rating Options—Hydrologic Soil Group (Rockridge Retirement Facility) Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Custom Soil Resource Report 27