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14 Garfield Street - Stormwater Report ............................................................................................................................ 1-1 .................................................................................................................... 2-1 ................................................................................................... 2-1 .......................................................................................................................... 2-1 ................................................................................................................................... 2-1 ..................................................... 2-1 ........................................................................................................ 2-2 ............................................................................................................................................... 2-2 ................................................................................................ 2-2 ........................................................................ 3-1 ............................................................................................................. 3-1 ................................................................................................................................ 3-2 .................................................................................................. 3-2 ................................................................................................ 3-2 ............................................................................................................... 3-2 ..................................................................................................................... 3-3 ................................................................ 3-3 ............................................................................. 3-6 ....................................................................................... 3-6 ................................................................................................... 3-6 ............. 3-6 ................. 3-6 .............................................................................. 3-7 ............. Error! Bookmark not defined. ............................................ 3-7 ................................................................................................................................ 4-1                    SITE R L A SCALE: DATE: JOB NO: ph: 413.568.0985 fax: 413.568.0986 rlaland.com 40 School Street · P.O. Box 640 · Westfield, MA 01086 R LEVESQUE ASSOCIATES, INC A Land Planning Services Company 210116 12/22/23 AS NOTED Proposed Residential Development 14 Garfield Street Northampton, MA 01062 NuWay Homes, Inc. (c/o Mr. John Handzel) 10 White Avenue East Longmeadow, MA 01028 FIG-1 SITE LOCUS USGS MAP SITE R L A SCALE: DATE: JOB NO: ph: 413.568.0985 fax: 413.568.0986 rlaland.com 40 School Street · P.O. Box 640 · Westfield, MA 01086 R LEVESQUE ASSOCIATES, INC A Land Planning Services Company 210116 12/22/23 AS NOTED Proposed Residential Development 14 Garfield Street Northampton, MA 01062 NuWay Homes, Inc. (c/o Mr. John Handzel) 10 White Avenue East Longmeadow, MA 01028 FIG-2 FLOOD RATE INSURANCE MAP SITE R L A SCALE: DATE: JOB NO: ph: 413.568.0985 fax: 413.568.0986 rlaland.com 40 School Street · P.O. Box 640 · Westfield, MA 01086 R LEVESQUE ASSOCIATES, INC A Land Planning Services Company 210116 12/22/23 AS NOTED Proposed Residential Development 14 Garfield Street Northampton, MA 01062 NuWay Homes, Inc. (c/o Mr. John Handzel) 10 White Avenue East Longmeadow, MA 01028 FIG-3 NHESP & Zone II Map 306B PAXTON FINE SANDY LOAM HYDROLOGIC GROUP: C GARFIELD STREET GARFIELD AVESTRAW AVESCALE: DATE: JOB NO.:ph: 413.568.0985 fax: 413.568.0986 rlaland.com40 School Street · P.O. Box 640 · Westfield, MA 01086R LEVESQUE ASSOCIATES, INCA Land Planning Services CompanyPre-DevelopmentWatershed PlanProposed Residential Development14 Garfield StreetNorthampton, MA 01062Nu-Way Homes Inc. (c/o Mr. John Handzel)10 White Avenue East Longmeadow, MA 01028210116 12/22/23 As Noted FIG-4 306B PAXTON FINE SANDY LOAM HYDROLOGIC GROUP: C GARFIELD STREET GARFIELD AVESTRAW AVEGARFIELD STREET GARFIELD AVESTRAW AVEPROPOSED 3 STORY W/F RESIDENCE PROPOSED 3 STORY W/F RESIDENCE SCALE: DATE: JOB NO.:ph: 413.568.0985 fax: 413.568.0986 rlaland.com40 School Street · P.O. Box 640 · Westfield, MA 01086R LEVESQUE ASSOCIATES, INCA Land Planning Services CompanyPost-DevelopmentWatershed PlanProposed Multi-Family Development14 Garfield StreetNorthampton, MA 01062Nu-Way Homes Inc. (c/o Mr. John Handzel)10 White Avenue East Longmeadow, MA 01028210116 12/22/2023 As Noted FIG-5 306B PAXTON FINE SANDY LOAM HYDROLOGIC GROUP: C GARFIELD STREET GARFIELD AVESTRAW AVEGARFIELD STREET GARFIELD AVESTRAW AVEPROPOSED 3 STORY W/F RESIDENCE PROPOSED 3 STORY W/F RESIDENCE SCALE: DATE: JOB NO.:ph: 413.568.0985 fax: 413.568.0986 rlaland.com40 School Street · P.O. Box 640 · Westfield, MA 01086R LEVESQUE ASSOCIATES, INCA Land Planning Services CompanyInlet AreaPlanProposed Residential Development14 Garfield StreetNorthampton, MA 01062Nu-Way Homes Inc. (c/o Mr. John Handzel)10 White Avenue East Longmeadow, MA 01028210116 12/22/2023 As Noted FIG-6 210116 - MassDEP Stormwater Checklist.doc • 04/01/08 Stormwater Report Checklist • Page 1 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report A. Introduction Important: When filling out forms on the computer, use only the tab key to move your cursor - do not use the return key. A Stormwater Report must be submitted with the Notice of Intent permit application to document compliance with the Stormwater Management Standards. The following checklist is NOT a substitute for the Stormwater Report (which should provide more substantive and detailed information) but is offered here as a tool to help the applicant organize their Stormwater Management documentation for their Report and for the reviewer to assess this information in a consistent format. As noted in the Checklist, the Stormwater Report must contain the engineering computations and supporting information set forth in Volume 3 of the Massachusetts Stormwater Handbook. The Stormwater Report must be prepared and certified by a Registered Professional Engineer (RPE) licensed in the Commonwealth. The Stormwater Report must include:  The Stormwater Checklist completed and stamped by a Registered Professional Engineer (see page 2) that certifies that the Stormwater Report contains all required submittals.1 This Checklist is to be used as the cover for the completed Stormwater Report.  Applicant/Project Name  Project Address  Name of Firm and Registered Professional Engineer that prepared the Report  Long-Term Pollution Prevention Plan required by Standards 4-6  Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan required by Standard 82  Operation and Maintenance Plan required by Standard 9 In addition to all plans and supporting information, the Stormwater Report must include a brief narrative describing stormwater management practices, including environmentally sensitive site design and LID techniques, along with a diagram depicting runoff through the proposed BMP treatment train. Plans are required to show existing and proposed conditions, identify all wetland resource areas, NRCS soil types, critical areas, Land Uses with Higher Potential Pollutant Loads (LUHPPL), and any areas on the site where infiltration rate is greater than 2.4 inches per hour. The Plans shall identify the drainage areas for both existing and proposed conditions at a scale that enables verification of supporting calculations. As noted in the Checklist, the Stormwater Management Report shall document compliance with each of the Stormwater Management Standards as provided in the Massachusetts Stormwater Handbook. The soils evaluation and calculations shall be done using the methodologies set forth in Volume 3 of the Massachusetts Stormwater Handbook. To ensure that the Stormwater Report is complete, applicants are required to fill in the Stormwater Report Checklist by checking the box to indicate that the specified information has been included in the Stormwater Report. If any of the information specified in the checklist has not been submitted, the applicant must provide an explanation. The completed Stormwater Report Checklist and Certification must be submitted with the Stormwater Report. 1 The Stormwater Report may also include the Illicit Discharge Compliance Statement required by Standard 10. If not included in the Stormwater Report, the Illicit Discharge Compliance Statement must be submitted prior to the discharge of stormwater runoff to the post-construction best management practices. 2 For some complex projects, it may not be possible to include the Construction Period Erosion and Sedimentation Control Plan in the Stormwater Report. In that event, the issuing authority has the discretion to issue an Order of Conditions that approves the project and includes a condition requiring the proponent to submit the Construction Period Erosion and Sedimentation Control Plan before commencing any land disturbance activity on the site. 210116 - MassDEP Stormwater Checklist.doc • 04/01/08 Stormwater Report Checklist • Page 2 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report B. Stormwater Checklist and Certification The following checklist is intended to serve as a guide for applicants as to the elements that ordinarily need to be addressed in a complete Stormwater Report. The checklist is also intended to provide conservation commissions and other reviewing authorities with a summary of the components necessary for a comprehensive Stormwater Report that addresses the ten Stormwater Standards. Note: Because stormwater requirements vary from project to project, it is possible that a complete Stormwater Report may not include information on some of the subjects specified in the Checklist. If it is determined that a specific item does not apply to the project under review, please note that the item is not applicable (N.A.) and provide the reasons for that determination. A complete checklist must include the Certification set forth below signed by the Registered Professional Engineer who prepared the Stormwater Report. Registered Professional Engineer’s Certification I have reviewed the Stormwater Report, including the soil evaluation, computations, Long-term Pollution Prevention Plan, the Construction Period Erosion and Sedimentation Control Plan (if included), the Long- term Post-Construction Operation and Maintenance Plan, the Illicit Discharge Compliance Statement (if included) and the plans showing the stormwater management system, and have determined that they have been prepared in accordance with the requirements of the Stormwater Management Standards as further elaborated by the Massachusetts Stormwater Handbook. I have also determined that the information presented in the Stormwater Checklist is accurate and that the information presented in the Stormwater Report accurately reflects conditions at the site as of the date of this permit application. Registered Professional Engineer Block and Signature Signature and Date Checklist Project Type: Is the application for new development, redevelopment, or a mix of new and redevelopment? New development Redevelopment Mix of New Development and Redevelopment 210116 - MassDEP Stormwater Checklist.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): Proprietary sedimentation device and subsurface infiltration basin 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. 210116 - MassDEP Stormwater Checklist.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. 210116 - MassDEP Stormwater Checklist.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. 210116 - MassDEP Stormwater Checklist.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. 210116 - MassDEP Stormwater Checklist.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. 210116 - MassDEP Stormwater Checklist.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. 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 Natural Resources Conservation Service November 30, 2023 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................12 Map Unit Descriptions........................................................................................12 Hampshire County, Massachusetts, Central Part...........................................14 306B—Paxton fine sandy loam, 0 to 8 percent slopes, very stony.............14 References............................................................................................................16 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 468981646898244689832468984046898484689856468986446898724689880468981646898244689832468984046898484689856468986446898724689880692447 692455 692463 692471 692479 692487 692447 692455 692463 692471 692479 692487 692495 42° 20' 14'' N 72° 39' 50'' W42° 20' 14'' N72° 39' 48'' W42° 20' 12'' N 72° 39' 50'' W42° 20' 12'' N 72° 39' 48'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 15 30 60 90 Feet 0 4 9 18 27 Meters Map Scale: 1:319 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. 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: 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 18, Sep 10, 2023 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Oct 15, 2020—Oct 31, 2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background Custom Soil Resource Report 10 MAP LEGEND MAP INFORMATION imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 11 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 306B Paxton fine sandy loam, 0 to 8 percent slopes, very stony 0.4 100.0% Totals for Area of Interest 0.4 100.0% 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 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. Custom Soil Resource Report 12 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 13 Hampshire County, Massachusetts, Central Part 306B—Paxton fine sandy loam, 0 to 8 percent slopes, very stony Map Unit Setting National map unit symbol: 2w673 Elevation: 0 to 1,340 feet Mean annual precipitation: 36 to 71 inches Mean annual air temperature: 39 to 55 degrees F Frost-free period: 140 to 240 days Farmland classification: Farmland of statewide importance Map Unit Composition Paxton, very stony, and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Paxton, Very Stony Setting Landform:Ground moraines, hills, drumlins Landform position (two-dimensional):Summit, shoulder, backslope Landform position (three-dimensional):Crest, side slope Down-slope shape:Convex, linear Across-slope shape:Linear, convex Parent material:Coarse-loamy lodgment till derived from gneiss, granite, and/or schist Typical profile Oe - 0 to 2 inches: moderately decomposed plant material A - 2 to 10 inches: fine sandy loam Bw1 - 10 to 17 inches: fine sandy loam Bw2 - 17 to 28 inches: fine sandy loam Cd - 28 to 67 inches: gravelly fine sandy loam Properties and qualities Slope:0 to 8 percent Surface area covered with cobbles, stones or boulders:1.6 percent Depth to restrictive feature:20 to 43 inches to densic material Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Very low to moderately low (0.00 to 0.14 in/hr) Depth to water table:About 18 to 37 inches Frequency of flooding:None Frequency of ponding:None Maximum salinity:Nonsaline (0.0 to 1.9 mmhos/cm) Available water supply, 0 to 60 inches: Low (about 4.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6s Hydrologic Soil Group: C Ecological site: F144AY007CT - Well Drained Dense Till Uplands Hydric soil rating: No Custom Soil Resource Report 14 Minor Components Woodbridge, very stony Percent of map unit:8 percent Landform:Ground moraines, hills, drumlins Landform position (two-dimensional):Summit, backslope, footslope Landform position (three-dimensional):Crest, side slope Down-slope shape:Concave Across-slope shape:Linear Hydric soil rating: No Ridgebury, very stony Percent of map unit:4 percent Landform:Drumlins, drainageways, depressions, hills, ground moraines Landform position (two-dimensional):Footslope, toeslope Landform position (three-dimensional):Head slope, base slope Down-slope shape:Concave Across-slope shape:Concave Hydric soil rating: Yes Charlton, very stony Percent of map unit:3 percent Landform:Hills Landform position (two-dimensional):Summit, shoulder, backslope Landform position (three-dimensional):Crest, side slope Down-slope shape:Convex Across-slope shape:Convex Hydric soil rating: No Custom Soil Resource Report 15 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 16 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 17 ES-1 ES-2 DP-1 Off-Site (Towards Garfield St) DP-2 Off-Site (Towards the South) Routing Diagram for 210116 - PREPrepared by R Levesque Associates, Printed 12/6/2023 HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Subcat Reach Pond Link 210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 2HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Rainfall Events Listing Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 2-Year Type III 24-hr Default 24.00 1 3.09 2 2 10-Year Type III 24-hr Default 24.00 1 4.96 2 3 100-Year Type III 24-hr Default 24.00 1 7.92 2 Type III 24-hr 2-Year Rainfall=3.09"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 3HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Time span=0.00-48.00 hrs, dt=0.03 hrs, 1601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=5,580 sf 0.00% Impervious Runoff Depth=0.97"Subcatchment ES-1: Tc=6.0 min CN=74 Runoff=0.1 cfs 449 cf Runoff Area=9,944 sf 0.00% Impervious Runoff Depth=0.97"Subcatchment ES-2: Tc=6.0 min CN=74 Runoff=0.2 cfs 800 cf Inflow=0.1 cfs 449 cfLink DP-1: Off-Site (Towards Garfield St) Primary=0.1 cfs 449 cf Inflow=0.2 cfs 800 cfLink DP-2: Off-Site (Towards the South) Primary=0.2 cfs 800 cf Total Runoff Area = 15,525 sf Runoff Volume = 1,250 cf Average Runoff Depth = 0.97" 100.00% Pervious = 15,525 sf 0.00% Impervious = 0 sf Type III 24-hr 2-Year Rainfall=3.09"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 4HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment ES-1: Runoff = 0.1 cfs @ 12.10 hrs, Volume= 449 cf, Depth= 0.97" Routed to Link DP-1 : Off-Site (Towards Garfield St) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 2-Year Rainfall=3.09" Area (sf) CN Description 5,580 74 >75% Grass cover, Good, HSG C 5,580 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment ES-1: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=3.09" Runoff Area=5,580 sf Runoff Volume=449 cf Runoff Depth=0.97" Tc=6.0 min CN=74 0.1 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 5HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment ES-2: Runoff = 0.2 cfs @ 12.10 hrs, Volume= 800 cf, Depth= 0.97" Routed to Link DP-2 : Off-Site (Towards the South) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 2-Year Rainfall=3.09" Area (sf) CN Description 9,944 74 >75% Grass cover, Good, HSG C 9,944 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment ES-2: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=3.09" Runoff Area=9,944 sf Runoff Volume=800 cf Runoff Depth=0.97" Tc=6.0 min CN=74 0.2 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 6HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-1: Off-Site (Towards Garfield St) Inflow Area = 5,580 sf, 0.00% Impervious, Inflow Depth = 0.97" for 2-Year event Inflow = 0.1 cfs @ 12.10 hrs, Volume= 449 cf Primary = 0.1 cfs @ 12.10 hrs, Volume= 449 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-1: Off-Site (Towards Garfield St) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=5,580 sf0.1 cfs 0.1 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 7HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-2: Off-Site (Towards the South) Inflow Area = 9,944 sf, 0.00% Impervious, Inflow Depth = 0.97" for 2-Year event Inflow = 0.2 cfs @ 12.10 hrs, Volume= 800 cf Primary = 0.2 cfs @ 12.10 hrs, Volume= 800 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-2: Off-Site (Towards the South) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=9,944 sf0.2 cfs 0.2 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 8HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Time span=0.00-48.00 hrs, dt=0.03 hrs, 1601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=5,580 sf 0.00% Impervious Runoff Depth=2.33"Subcatchment ES-1: Tc=6.0 min CN=74 Runoff=0.3 cfs 1,085 cf Runoff Area=9,944 sf 0.00% Impervious Runoff Depth=2.33"Subcatchment ES-2: Tc=6.0 min CN=74 Runoff=0.6 cfs 1,933 cf Inflow=0.3 cfs 1,085 cfLink DP-1: Off-Site (Towards Garfield St) Primary=0.3 cfs 1,085 cf Inflow=0.6 cfs 1,933 cfLink DP-2: Off-Site (Towards the South) Primary=0.6 cfs 1,933 cf Total Runoff Area = 15,525 sf Runoff Volume = 3,017 cf Average Runoff Depth = 2.33" 100.00% Pervious = 15,525 sf 0.00% Impervious = 0 sf Type III 24-hr 10-Year Rainfall=4.96"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 9HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment ES-1: Runoff = 0.3 cfs @ 12.09 hrs, Volume= 1,085 cf, Depth= 2.33" Routed to Link DP-1 : Off-Site (Towards Garfield St) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 10-Year Rainfall=4.96" Area (sf) CN Description 5,580 74 >75% Grass cover, Good, HSG C 5,580 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment ES-1: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=4.96" Runoff Area=5,580 sf Runoff Volume=1,085 cf Runoff Depth=2.33" Tc=6.0 min CN=74 0.3 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 10HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment ES-2: Runoff = 0.6 cfs @ 12.09 hrs, Volume= 1,933 cf, Depth= 2.33" Routed to Link DP-2 : Off-Site (Towards the South) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 10-Year Rainfall=4.96" Area (sf) CN Description 9,944 74 >75% Grass cover, Good, HSG C 9,944 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment ES-2: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=4.96" Runoff Area=9,944 sf Runoff Volume=1,933 cf Runoff Depth=2.33" Tc=6.0 min CN=74 0.6 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 11HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-1: Off-Site (Towards Garfield St) Inflow Area = 5,580 sf, 0.00% Impervious, Inflow Depth = 2.33" for 10-Year event Inflow = 0.3 cfs @ 12.09 hrs, Volume= 1,085 cf Primary = 0.3 cfs @ 12.09 hrs, Volume= 1,085 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-1: Off-Site (Towards Garfield St) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=5,580 sf0.3 cfs 0.3 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 12HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-2: Off-Site (Towards the South) Inflow Area = 9,944 sf, 0.00% Impervious, Inflow Depth = 2.33" for 10-Year event Inflow = 0.6 cfs @ 12.09 hrs, Volume= 1,933 cf Primary = 0.6 cfs @ 12.09 hrs, Volume= 1,933 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-2: Off-Site (Towards the South) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=9,944 sf0.6 cfs 0.6 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 13HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Time span=0.00-48.00 hrs, dt=0.03 hrs, 1601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=5,580 sf 0.00% Impervious Runoff Depth=4.85"Subcatchment ES-1: Tc=6.0 min CN=74 Runoff=0.7 cfs 2,257 cf Runoff Area=9,944 sf 0.00% Impervious Runoff Depth=4.85"Subcatchment ES-2: Tc=6.0 min CN=74 Runoff=1.3 cfs 4,023 cf Inflow=0.7 cfs 2,257 cfLink DP-1: Off-Site (Towards Garfield St) Primary=0.7 cfs 2,257 cf Inflow=1.3 cfs 4,023 cfLink DP-2: Off-Site (Towards the South) Primary=1.3 cfs 4,023 cf Total Runoff Area = 15,525 sf Runoff Volume = 6,280 cf Average Runoff Depth = 4.85" 100.00% Pervious = 15,525 sf 0.00% Impervious = 0 sf Type III 24-hr 100-Year Rainfall=7.92"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 14HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment ES-1: Runoff = 0.7 cfs @ 12.09 hrs, Volume= 2,257 cf, Depth= 4.85" Routed to Link DP-1 : Off-Site (Towards Garfield St) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 100-Year Rainfall=7.92" Area (sf) CN Description 5,580 74 >75% Grass cover, Good, HSG C 5,580 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment ES-1: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=7.92" Runoff Area=5,580 sf Runoff Volume=2,257 cf Runoff Depth=4.85" Tc=6.0 min CN=74 0.7 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 15HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment ES-2: Runoff = 1.3 cfs @ 12.09 hrs, Volume= 4,023 cf, Depth= 4.85" Routed to Link DP-2 : Off-Site (Towards the South) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 100-Year Rainfall=7.92" Area (sf) CN Description 9,944 74 >75% Grass cover, Good, HSG C 9,944 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment ES-2: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)1 0 Type III 24-hr 100-Year Rainfall=7.92" Runoff Area=9,944 sf Runoff Volume=4,023 cf Runoff Depth=4.85" Tc=6.0 min CN=74 1.3 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 16HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-1: Off-Site (Towards Garfield St) Inflow Area = 5,580 sf, 0.00% Impervious, Inflow Depth = 4.85" for 100-Year event Inflow = 0.7 cfs @ 12.09 hrs, Volume= 2,257 cf Primary = 0.7 cfs @ 12.09 hrs, Volume= 2,257 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-1: Off-Site (Towards Garfield St) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=5,580 sf0.7 cfs 0.7 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - PRE Printed 12/6/2023Prepared by R Levesque Associates Page 17HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-2: Off-Site (Towards the South) Inflow Area = 9,944 sf, 0.00% Impervious, Inflow Depth = 4.85" for 100-Year event Inflow = 1.3 cfs @ 12.09 hrs, Volume= 4,023 cf Primary = 1.3 cfs @ 12.09 hrs, Volume= 4,023 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-2: Off-Site (Towards the South) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)1 0 Inflow Area=9,944 sf1.3 cfs 1.3 cfs PS-1a PS-1b PS-2 1P Subsurface Infiltration Basin DP-1 Off-Site (Towards Garfield St) DP-2 Off-Site (Towards the South) Routing Diagram for 210116 - POSTPrepared by R Levesque Associates, Printed 12/8/2023 HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Subcat Reach Pond Link 210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 2HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Rainfall Events Listing Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 2-Year Type III 24-hr Default 24.00 1 3.09 2 2 10-Year Type III 24-hr Default 24.00 1 4.96 2 3 100-Year Type III 24-hr Default 24.00 1 7.92 2 Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 3HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Time span=0.00-48.00 hrs, dt=0.03 hrs, 1601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=2,370 sf 13.18% Impervious Runoff Depth=1.22"Subcatchment PS-1a: Tc=6.0 min CN=WQ Runoff=0.1 cfs 240 cf Runoff Area=10,863 sf 91.77% Impervious Runoff Depth=2.70"Subcatchment PS-1b: Tc=6.0 min CN=WQ Runoff=0.7 cfs 2,446 cf Runoff Area=2,292 sf 0.08% Impervious Runoff Depth=0.97"Subcatchment PS-2: Tc=6.0 min CN=WQ Runoff=0.1 cfs 185 cf Peak Elev=248.85' Storage=754 cf Inflow=0.7 cfs 2,446 cfPond 1P: Subsurface Infiltration Basin Discarded=0.1 cfs 2,446 cf Primary=0.0 cfs 0 cf Outflow=0.1 cfs 2,446 cf Inflow=0.1 cfs 240 cfLink DP-1: Off-Site (Towards Garfield St) Primary=0.1 cfs 240 cf Inflow=0.1 cfs 185 cfLink DP-2: Off-Site (Towards the South) Primary=0.1 cfs 185 cf Total Runoff Area = 15,525 sf Runoff Volume = 2,871 cf Average Runoff Depth = 2.22" 33.77% Pervious = 5,242 sf 66.23% Impervious = 10,282 sf Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 4HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-1a: Runoff = 0.1 cfs @ 12.09 hrs, Volume= 240 cf, Depth= 1.22" Routed to Link DP-1 : Off-Site (Towards Garfield St) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 2-Year Rainfall=3.09" Area (sf) CN Description 2,058 74 >75% Grass cover, Good, HSG C 163 98 Paved parking, HSG C 150 98 Roofs, HSG C 2,370 Weighted Average 2,058 74 86.82% Pervious Area 312 98 13.18% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-1a: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=3.09" Runoff Area=2,370 sf Runoff Volume=240 cf Runoff Depth=1.22" Tc=6.0 min CN=WQ 0.1 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 5HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-1b: Runoff = 0.7 cfs @ 12.08 hrs, Volume= 2,446 cf, Depth= 2.70" Routed to Pond 1P : Subsurface Infiltration Basin Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 2-Year Rainfall=3.09" Area (sf) CN Description 894 74 >75% Grass cover, Good, HSG C 6,844 98 Paved parking, HSG C 3,124 98 Roofs, HSG C 10,863 Weighted Average 894 74 8.23% Pervious Area 9,968 98 91.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-1b: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=3.09" Runoff Area=10,863 sf Runoff Volume=2,446 cf Runoff Depth=2.70" Tc=6.0 min CN=WQ 0.7 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 6HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-2: Runoff = 0.1 cfs @ 12.10 hrs, Volume= 185 cf, Depth= 0.97" Routed to Link DP-2 : Off-Site (Towards the South) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 2-Year Rainfall=3.09" Area (sf) CN Description 2,290 74 >75% Grass cover, Good, HSG C 2 98 Roofs, HSG C 2,292 Weighted Average 2,290 74 99.92% Pervious Area 2 98 0.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-2: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=3.09" Runoff Area=2,292 sf Runoff Volume=185 cf Runoff Depth=0.97" Tc=6.0 min CN=WQ 0.1 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 7HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Pond 1P: Subsurface Infiltration Basin Inflow Area = 10,863 sf, 91.77% Impervious, Inflow Depth = 2.70" for 2-Year event Inflow = 0.7 cfs @ 12.08 hrs, Volume= 2,446 cf Outflow = 0.1 cfs @ 11.64 hrs, Volume= 2,446 cf, Atten= 88%, Lag= 0.0 min Discarded = 0.1 cfs @ 11.64 hrs, Volume= 2,446 cf Primary = 0.0 cfs @ 0.00 hrs, Volume= 0 cf Routed to Link DP-1 : Off-Site (Towards Garfield St) Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Peak Elev= 248.85' @ 12.64 hrs Surf.Area= 1,573 sf Storage= 754 cf Plug-Flow detention time= 55.1 min calculated for 2,446 cf (100% of inflow) Center-of-Mass det. time= 55.1 min ( 815.4 - 760.3 ) Volume Invert Avail.Storage Storage Description #1A 248.00' 1,467 cf 49.00'W x 32.10'L x 3.50'H Field A 5,505 cf Overall - 1,838 cf Embedded = 3,667 cf x 40.0% Voids #2A 248.50' 1,838 cf ADS_StormTech SC-740 +Cap x 40 Inside #1 Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 40 Chambers in 10 Rows 3,304 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routing Invert Outlet Devices #1 Primary 249.90'8.0" Round Culvert L= 93.2' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 249.90' / 249.28' S= 0.0067 '/' Cc= 0.900 n= 0.013, Flow Area= 0.35 sf #2 Device 1 251.25'4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Discarded 248.00'2.410 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.1 cfs @ 11.64 hrs HW=248.04' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.1 cfs) Primary OutFlow Max=0.0 cfs @ 0.00 hrs HW=248.00' (Free Discharge) 1=Culvert ( Controls 0.0 cfs) 2=Sharp-Crested Rectangular Weir ( Controls 0.0 cfs) Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 8HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Pond 1P: Subsurface Infiltration Basin - Chamber Wizard Field A Chamber Model = ADS_StormTech SC-740 +Cap (ADS StormTech® SC-740 with cap length) Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 51.0" Wide + 6.0" Spacing = 57.0" C-C Row Spacing 4 Chambers/Row x 7.12' Long +0.81' Cap Length x 2 = 30.10' Row Length +12.0" End Stone x 2 = 32.10' Base Length 10 Rows x 51.0" Wide + 6.0" Spacing x 9 + 12.0" Side Stone x 2 = 49.00' Base Width 6.0" Stone Base + 30.0" Chamber Height + 6.0" Stone Cover = 3.50' Field Height 40 Chambers x 45.9 cf = 1,837.6 cf Chamber Storage 5,504.6 cf Field - 1,837.6 cf Chambers = 3,667.0 cf Stone x 40.0% Voids = 1,466.8 cf Stone Storage Chamber Storage + Stone Storage = 3,304.4 cf = 0.076 af Overall Storage Efficiency = 60.0% Overall System Size = 32.10' x 49.00' x 3.50' 40 Chambers 203.9 cy Field 135.8 cy Stone Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 9HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Pond 1P: Subsurface Infiltration Basin Inflow Outflow Discarded Primary Hydrograph Time (hours)484644424038363432302826242220181614121086420Flow (cfs)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=10,863 sf Peak Elev=248.85' Storage=754 cf 0.7 cfs 0.1 cfs 0.1 cfs 0.0 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 10HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-1: Off-Site (Towards Garfield St) Inflow Area = 13,233 sf, 77.69% Impervious, Inflow Depth = 0.22" for 2-Year event Inflow = 0.1 cfs @ 12.09 hrs, Volume= 240 cf Primary = 0.1 cfs @ 12.09 hrs, Volume= 240 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-1: Off-Site (Towards Garfield St) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=13,233 sf0.1 cfs 0.1 cfs Type III 24-hr 2-Year Rainfall=3.09"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 11HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-2: Off-Site (Towards the South) Inflow Area = 2,292 sf, 0.08% Impervious, Inflow Depth = 0.97" for 2-Year event Inflow = 0.1 cfs @ 12.10 hrs, Volume= 185 cf Primary = 0.1 cfs @ 12.10 hrs, Volume= 185 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-2: Off-Site (Towards the South) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=2,292 sf0.1 cfs 0.1 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 12HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Time span=0.00-48.00 hrs, dt=0.03 hrs, 1601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=2,370 sf 13.18% Impervious Runoff Depth=2.65"Subcatchment PS-1a: Tc=6.0 min CN=WQ Runoff=0.2 cfs 523 cf Runoff Area=10,863 sf 91.77% Impervious Runoff Depth=4.53"Subcatchment PS-1b: Tc=6.0 min CN=WQ Runoff=1.2 cfs 4,097 cf Runoff Area=2,292 sf 0.08% Impervious Runoff Depth=2.33"Subcatchment PS-2: Tc=6.0 min CN=WQ Runoff=0.1 cfs 446 cf Peak Elev=249.49' Storage=1,532 cf Inflow=1.2 cfs 4,097 cfPond 1P: Subsurface Infiltration Basin Discarded=0.1 cfs 4,097 cf Primary=0.0 cfs 0 cf Outflow=0.1 cfs 4,097 cf Inflow=0.2 cfs 523 cfLink DP-1: Off-Site (Towards Garfield St) Primary=0.2 cfs 523 cf Inflow=0.1 cfs 446 cfLink DP-2: Off-Site (Towards the South) Primary=0.1 cfs 446 cf Total Runoff Area = 15,525 sf Runoff Volume = 5,066 cf Average Runoff Depth = 3.92" 33.77% Pervious = 5,242 sf 66.23% Impervious = 10,282 sf Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 13HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-1a: Runoff = 0.2 cfs @ 12.09 hrs, Volume= 523 cf, Depth= 2.65" Routed to Link DP-1 : Off-Site (Towards Garfield St) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 10-Year Rainfall=4.96" Area (sf) CN Description 2,058 74 >75% Grass cover, Good, HSG C 163 98 Paved parking, HSG C 150 98 Roofs, HSG C 2,370 Weighted Average 2,058 74 86.82% Pervious Area 312 98 13.18% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-1a: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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 10-Year Rainfall=4.96" Runoff Area=2,370 sf Runoff Volume=523 cf Runoff Depth=2.65" Tc=6.0 min CN=WQ 0.2 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 14HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-1b: Runoff = 1.2 cfs @ 12.08 hrs, Volume= 4,097 cf, Depth= 4.53" Routed to Pond 1P : Subsurface Infiltration Basin Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 10-Year Rainfall=4.96" Area (sf) CN Description 894 74 >75% Grass cover, Good, HSG C 6,844 98 Paved parking, HSG C 3,124 98 Roofs, HSG C 10,863 Weighted Average 894 74 8.23% Pervious Area 9,968 98 91.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-1b: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)1 0 Type III 24-hr 10-Year Rainfall=4.96" Runoff Area=10,863 sf Runoff Volume=4,097 cf Runoff Depth=4.53" Tc=6.0 min CN=WQ 1.2 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 15HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-2: Runoff = 0.1 cfs @ 12.09 hrs, Volume= 446 cf, Depth= 2.33" Routed to Link DP-2 : Off-Site (Towards the South) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 10-Year Rainfall=4.96" Area (sf) CN Description 2,290 74 >75% Grass cover, Good, HSG C 2 98 Roofs, HSG C 2,292 Weighted Average 2,290 74 99.92% Pervious Area 2 98 0.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-2: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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 10-Year Rainfall=4.96" Runoff Area=2,292 sf Runoff Volume=446 cf Runoff Depth=2.33" Tc=6.0 min CN=WQ 0.1 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 16HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Pond 1P: Subsurface Infiltration Basin Inflow Area = 10,863 sf, 91.77% Impervious, Inflow Depth = 4.53" for 10-Year event Inflow = 1.2 cfs @ 12.08 hrs, Volume= 4,097 cf Outflow = 0.1 cfs @ 11.19 hrs, Volume= 4,097 cf, Atten= 92%, Lag= 0.0 min Discarded = 0.1 cfs @ 11.19 hrs, Volume= 4,097 cf Primary = 0.0 cfs @ 0.00 hrs, Volume= 0 cf Routed to Link DP-1 : Off-Site (Towards Garfield St) Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Peak Elev= 249.49' @ 13.14 hrs Surf.Area= 1,573 sf Storage= 1,532 cf Plug-Flow detention time= 129.3 min calculated for 4,097 cf (100% of inflow) Center-of-Mass det. time= 129.2 min ( 881.2 - 752.0 ) Volume Invert Avail.Storage Storage Description #1A 248.00' 1,467 cf 49.00'W x 32.10'L x 3.50'H Field A 5,505 cf Overall - 1,838 cf Embedded = 3,667 cf x 40.0% Voids #2A 248.50' 1,838 cf ADS_StormTech SC-740 +Cap x 40 Inside #1 Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 40 Chambers in 10 Rows 3,304 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routing Invert Outlet Devices #1 Primary 249.90'8.0" Round Culvert L= 93.2' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 249.90' / 249.28' S= 0.0067 '/' Cc= 0.900 n= 0.013, Flow Area= 0.35 sf #2 Device 1 251.25'4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Discarded 248.00'2.410 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.1 cfs @ 11.19 hrs HW=248.04' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.1 cfs) Primary OutFlow Max=0.0 cfs @ 0.00 hrs HW=248.00' (Free Discharge) 1=Culvert ( Controls 0.0 cfs) 2=Sharp-Crested Rectangular Weir ( Controls 0.0 cfs) Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 17HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Pond 1P: Subsurface Infiltration Basin - Chamber Wizard Field A Chamber Model = ADS_StormTech SC-740 +Cap (ADS StormTech® SC-740 with cap length) Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 51.0" Wide + 6.0" Spacing = 57.0" C-C Row Spacing 4 Chambers/Row x 7.12' Long +0.81' Cap Length x 2 = 30.10' Row Length +12.0" End Stone x 2 = 32.10' Base Length 10 Rows x 51.0" Wide + 6.0" Spacing x 9 + 12.0" Side Stone x 2 = 49.00' Base Width 6.0" Stone Base + 30.0" Chamber Height + 6.0" Stone Cover = 3.50' Field Height 40 Chambers x 45.9 cf = 1,837.6 cf Chamber Storage 5,504.6 cf Field - 1,837.6 cf Chambers = 3,667.0 cf Stone x 40.0% Voids = 1,466.8 cf Stone Storage Chamber Storage + Stone Storage = 3,304.4 cf = 0.076 af Overall Storage Efficiency = 60.0% Overall System Size = 32.10' x 49.00' x 3.50' 40 Chambers 203.9 cy Field 135.8 cy Stone Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 18HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Pond 1P: Subsurface Infiltration Basin Inflow Outflow Discarded Primary Hydrograph Time (hours)484644424038363432302826242220181614121086420Flow (cfs)1 0 Inflow Area=10,863 sf Peak Elev=249.49' Storage=1,532 cf 1.2 cfs 0.1 cfs 0.1 cfs 0.0 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 19HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-1: Off-Site (Towards Garfield St) Inflow Area = 13,233 sf, 77.69% Impervious, Inflow Depth = 0.47" for 10-Year event Inflow = 0.2 cfs @ 12.09 hrs, Volume= 523 cf Primary = 0.2 cfs @ 12.09 hrs, Volume= 523 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-1: Off-Site (Towards Garfield St) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=13,233 sf0.2 cfs 0.2 cfs Type III 24-hr 10-Year Rainfall=4.96"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 20HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-2: Off-Site (Towards the South) Inflow Area = 2,292 sf, 0.08% Impervious, Inflow Depth = 2.33" for 10-Year event Inflow = 0.1 cfs @ 12.09 hrs, Volume= 446 cf Primary = 0.1 cfs @ 12.09 hrs, Volume= 446 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-2: Off-Site (Towards the South) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=2,292 sf0.1 cfs 0.1 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 21HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Time span=0.00-48.00 hrs, dt=0.03 hrs, 1601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=2,370 sf 13.18% Impervious Runoff Depth=5.23"Subcatchment PS-1a: Tc=6.0 min CN=WQ Runoff=0.3 cfs 1,032 cf Runoff Area=10,863 sf 91.77% Impervious Runoff Depth=7.45"Subcatchment PS-1b: Tc=6.0 min CN=WQ Runoff=1.9 cfs 6,742 cf Runoff Area=2,292 sf 0.08% Impervious Runoff Depth=4.86"Subcatchment PS-2: Tc=6.0 min CN=WQ Runoff=0.3 cfs 928 cf Peak Elev=251.17' Storage=3,095 cf Inflow=1.9 cfs 6,742 cfPond 1P: Subsurface Infiltration Basin Discarded=0.1 cfs 6,742 cf Primary=0.0 cfs 0 cf Outflow=0.1 cfs 6,742 cf Inflow=0.3 cfs 1,032 cfLink DP-1: Off-Site (Towards Garfield St) Primary=0.3 cfs 1,032 cf Inflow=0.3 cfs 928 cfLink DP-2: Off-Site (Towards the South) Primary=0.3 cfs 928 cf Total Runoff Area = 15,525 sf Runoff Volume = 8,701 cf Average Runoff Depth = 6.73" 33.77% Pervious = 5,242 sf 66.23% Impervious = 10,282 sf Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 22HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-1a: Runoff = 0.3 cfs @ 12.09 hrs, Volume= 1,032 cf, Depth= 5.23" Routed to Link DP-1 : Off-Site (Towards Garfield St) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 100-Year Rainfall=7.92" Area (sf) CN Description 2,058 74 >75% Grass cover, Good, HSG C 163 98 Paved parking, HSG C 150 98 Roofs, HSG C 2,370 Weighted Average 2,058 74 86.82% Pervious Area 312 98 13.18% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-1a: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=7.92" Runoff Area=2,370 sf Runoff Volume=1,032 cf Runoff Depth=5.23" Tc=6.0 min CN=WQ 0.3 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 23HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-1b: Runoff = 1.9 cfs @ 12.08 hrs, Volume= 6,742 cf, Depth= 7.45" Routed to Pond 1P : Subsurface Infiltration Basin Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 100-Year Rainfall=7.92" Area (sf) CN Description 894 74 >75% Grass cover, Good, HSG C 6,844 98 Paved parking, HSG C 3,124 98 Roofs, HSG C 10,863 Weighted Average 894 74 8.23% Pervious Area 9,968 98 91.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-1b: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)2 1 0 Type III 24-hr 100-Year Rainfall=7.92" Runoff Area=10,863 sf Runoff Volume=6,742 cf Runoff Depth=7.45" Tc=6.0 min CN=WQ 1.9 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 24HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PS-2: Runoff = 0.3 cfs @ 12.09 hrs, Volume= 928 cf, Depth= 4.86" Routed to Link DP-2 : Off-Site (Towards the South) Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 100-Year Rainfall=7.92" Area (sf) CN Description 2,290 74 >75% Grass cover, Good, HSG C 2 98 Roofs, HSG C 2,292 Weighted Average 2,290 74 99.92% Pervious Area 2 98 0.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PS-2: Runoff Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=7.92" Runoff Area=2,292 sf Runoff Volume=928 cf Runoff Depth=4.86" Tc=6.0 min CN=WQ 0.3 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 25HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Pond 1P: Subsurface Infiltration Basin Inflow Area = 10,863 sf, 91.77% Impervious, Inflow Depth = 7.45" for 100-Year event Inflow = 1.9 cfs @ 12.08 hrs, Volume= 6,742 cf Outflow = 0.1 cfs @ 10.05 hrs, Volume= 6,742 cf, Atten= 95%, Lag= 0.0 min Discarded = 0.1 cfs @ 10.05 hrs, Volume= 6,742 cf Primary = 0.0 cfs @ 0.00 hrs, Volume= 0 cf Routed to Link DP-1 : Off-Site (Towards Garfield St) Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Peak Elev= 251.17' @ 14.47 hrs Surf.Area= 1,573 sf Storage= 3,095 cf Plug-Flow detention time= 289.6 min calculated for 6,742 cf (100% of inflow) Center-of-Mass det. time= 289.6 min ( 1,034.9 - 745.4 ) Volume Invert Avail.Storage Storage Description #1A 248.00' 1,467 cf 49.00'W x 32.10'L x 3.50'H Field A 5,505 cf Overall - 1,838 cf Embedded = 3,667 cf x 40.0% Voids #2A 248.50' 1,838 cf ADS_StormTech SC-740 +Cap x 40 Inside #1 Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 40 Chambers in 10 Rows 3,304 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routing Invert Outlet Devices #1 Primary 249.90'8.0" Round Culvert L= 93.2' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 249.90' / 249.28' S= 0.0067 '/' Cc= 0.900 n= 0.013, Flow Area= 0.35 sf #2 Device 1 251.25'4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Discarded 248.00'2.410 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.1 cfs @ 10.05 hrs HW=248.04' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.1 cfs) Primary OutFlow Max=0.0 cfs @ 0.00 hrs HW=248.00' (Free Discharge) 1=Culvert ( Controls 0.0 cfs) 2=Sharp-Crested Rectangular Weir ( Controls 0.0 cfs) Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 26HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Pond 1P: Subsurface Infiltration Basin - Chamber Wizard Field A Chamber Model = ADS_StormTech SC-740 +Cap (ADS StormTech® SC-740 with cap length) Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 51.0" Wide + 6.0" Spacing = 57.0" C-C Row Spacing 4 Chambers/Row x 7.12' Long +0.81' Cap Length x 2 = 30.10' Row Length +12.0" End Stone x 2 = 32.10' Base Length 10 Rows x 51.0" Wide + 6.0" Spacing x 9 + 12.0" Side Stone x 2 = 49.00' Base Width 6.0" Stone Base + 30.0" Chamber Height + 6.0" Stone Cover = 3.50' Field Height 40 Chambers x 45.9 cf = 1,837.6 cf Chamber Storage 5,504.6 cf Field - 1,837.6 cf Chambers = 3,667.0 cf Stone x 40.0% Voids = 1,466.8 cf Stone Storage Chamber Storage + Stone Storage = 3,304.4 cf = 0.076 af Overall Storage Efficiency = 60.0% Overall System Size = 32.10' x 49.00' x 3.50' 40 Chambers 203.9 cy Field 135.8 cy Stone Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 27HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Pond 1P: Subsurface Infiltration Basin Inflow Outflow Discarded Primary Hydrograph Time (hours)484644424038363432302826242220181614121086420Flow (cfs)2 1 0 Inflow Area=10,863 sf Peak Elev=251.17' Storage=3,095 cf 1.9 cfs 0.1 cfs 0.1 cfs 0.0 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 28HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-1: Off-Site (Towards Garfield St) Inflow Area = 13,233 sf, 77.69% Impervious, Inflow Depth = 0.94" for 100-Year event Inflow = 0.3 cfs @ 12.09 hrs, Volume= 1,032 cf Primary = 0.3 cfs @ 12.09 hrs, Volume= 1,032 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-1: Off-Site (Towards Garfield St) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=13,233 sf0.3 cfs 0.3 cfs Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/8/2023Prepared by R Levesque Associates Page 29HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Link DP-2: Off-Site (Towards the South) Inflow Area = 2,292 sf, 0.08% Impervious, Inflow Depth = 4.86" for 100-Year event Inflow = 0.3 cfs @ 12.09 hrs, Volume= 928 cf Primary = 0.3 cfs @ 12.09 hrs, Volume= 928 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Link DP-2: Off-Site (Towards the South) InflowPrimary Hydrograph Time (hours) 484644424038363432302826242220181614121086420Flow (cfs)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=2,292 sf0.3 cfs 0.3 cfs NOAA Atlas 14, Volume 10, Version 3 Location name: Northampton, Massachusetts, USA* Latitude: 42.3108°, Longitude: -72.6478° Elevation: 201.41 ft** * source: ESRI Maps** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Sandra Pavlovic, Michael St. Laurent, Carl Trypaluk, Dale Unruh, Orlan Wilhite NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 0.328 (0.252‑0.421) 0.389 (0.298‑0.501) 0.489 (0.374‑0.632) 0.572 (0.435‑0.744) 0.687 (0.507‑0.934) 0.774 (0.560‑1.08) 0.864 (0.608‑1.25) 0.962 (0.645‑1.43) 1.10 (0.712‑1.69) 1.21 (0.766‑1.90) 10-min 0.464 (0.356‑0.597) 0.551 (0.423‑0.710) 0.693 (0.530‑0.896) 0.811 (0.617‑1.06) 0.973 (0.718‑1.32) 1.10 (0.793‑1.52) 1.22 (0.861‑1.76) 1.36 (0.914‑2.02) 1.56 (1.01‑2.40) 1.71 (1.09‑2.70) 15-min 0.546 (0.419‑0.702) 0.648 (0.497‑0.835) 0.815 (0.624‑1.05) 0.954 (0.726‑1.24) 1.15 (0.845‑1.56) 1.29 (0.933‑1.79) 1.44 (1.01‑2.08) 1.60 (1.08‑2.38) 1.83 (1.19‑2.82) 2.02 (1.28‑3.17) 30-min 0.750 (0.576‑0.965) 0.892 (0.684‑1.15) 1.12 (0.859‑1.45) 1.32 (0.999‑1.71) 1.58 (1.16‑2.14) 1.78 (1.29‑2.47) 1.98 (1.40‑2.86) 2.21 (1.48‑3.28) 2.53 (1.64‑3.89) 2.78 (1.76‑4.37) 60-min 0.955 (0.733‑1.23) 1.14 (0.871‑1.46) 1.43 (1.09‑1.85) 1.67 (1.27‑2.18) 2.01 (1.48‑2.73) 2.27 (1.64‑3.15) 2.53 (1.78‑3.65) 2.82 (1.89‑4.18) 3.22 (2.08‑4.95) 3.54 (2.24‑5.57) 2-hr 1.21 (0.939‑1.55) 1.44 (1.11‑1.84) 1.81 (1.40‑2.33) 2.12 (1.63‑2.74) 2.55 (1.90‑3.45) 2.87 (2.09‑3.97) 3.20 (2.28‑4.62) 3.59 (2.42‑5.30) 4.16 (2.70‑6.36) 4.63 (2.94‑7.24) 3-hr 1.38 (1.08‑1.76) 1.65 (1.28‑2.10) 2.09 (1.61‑2.66) 2.44 (1.88‑3.14) 2.94 (2.20‑3.97) 3.31 (2.43‑4.58) 3.71 (2.66‑5.36) 4.18 (2.82‑6.15) 4.89 (3.18‑7.46) 5.48 (3.49‑8.55) 6-hr 1.72 (1.35‑2.16) 2.08 (1.63‑2.62) 2.66 (2.08‑3.37) 3.15 (2.44‑4.01) 3.82 (2.89‑5.14) 4.32 (3.20‑5.96) 4.86 (3.52‑7.03) 5.53 (3.74‑8.09) 6.57 (4.28‑9.98) 7.47 (4.76‑11.6) 12-hr 2.10 (1.66‑2.62) 2.58 (2.04‑3.24) 3.39 (2.66‑4.26) 4.05 (3.17‑5.12) 4.97 (3.78‑6.65) 5.63 (4.22‑7.76) 6.38 (4.67‑9.23) 7.32 (4.98‑10.7) 8.82 (5.77‑13.3) 10.1 (6.49‑15.6) 24-hr 2.47 (1.97‑3.06) 3.09 (2.46‑3.84) 4.11 (3.26‑5.13) 4.96 (3.91‑6.23) 6.13 (4.70‑8.17) 6.98 (5.27‑9.57) 7.92 (5.86‑11.4) 9.16 (6.25‑13.3) 11.1 (7.32‑16.8) 12.9 (8.28‑19.8) 2-day 2.82 (2.27‑3.47) 3.56 (2.86‑4.38) 4.76 (3.80‑5.88) 5.75 (4.57‑7.16) 7.12 (5.51‑9.45) 8.12 (6.18‑11.1) 9.24 (6.89‑13.3) 10.7 (7.34‑15.4) 13.1 (8.65‑19.7) 15.3 (9.85‑23.4) 3-day 3.08(2.49‑3.77)3.88(3.13‑4.76)5.18(4.17‑6.38)6.26(5.00‑7.76)7.75(6.03‑10.2)8.83(6.75‑12.0)10.0(7.53‑14.4)11.7(8.01‑16.7)14.3(9.45‑21.4)16.7(10.8‑25.4) 4-day 3.31 (2.69‑4.04) 4.16 (3.36‑5.08) 5.54 (4.46‑6.79) 6.68 (5.35‑8.25) 8.26 (6.44‑10.9) 9.40 (7.20‑12.8) 10.7 (8.02‑15.3) 12.4 (8.53‑17.7) 15.2 (10.1‑22.6) 17.7 (11.5‑26.9) 7-day 3.96 (3.23‑4.80) 4.89 (3.99‑5.94) 6.42 (5.21‑7.82) 7.68 (6.20‑9.43) 9.43 (7.39‑12.3) 10.7 (8.23‑14.4) 12.1 (9.10‑17.2) 14.0 (9.66‑19.9) 17.0 (11.3‑25.1) 19.6 (12.7‑29.7) 10-day 4.60 (3.77‑5.56) 5.58 (4.57‑6.75) 7.19 (5.86‑8.72) 8.52 (6.90‑10.4) 10.4 (8.13‑13.4) 11.7 (9.00‑15.6) 13.2 (9.88‑18.5) 15.1 (10.4‑21.4) 18.1 (12.0‑26.6) 20.7 (13.4‑31.2) 20-day 6.64 (5.49‑7.94) 7.67 (6.34‑9.20) 9.37 (7.71‑11.3) 10.8 (8.80‑13.1) 12.7 (10.0‑16.2) 14.1 (10.9‑18.6) 15.7 (11.7‑21.5) 17.5 (12.2‑24.6) 20.2 (13.5‑29.6) 22.5 (14.6‑33.7) 30-day 8.33 (6.92‑9.92) 9.40 (7.80‑11.2) 11.1 (9.22‑13.4) 12.6 (10.3‑15.2) 14.6 (11.5‑18.5) 16.1 (12.4‑20.9) 17.7 (13.1‑23.9) 19.4 (13.6‑27.2) 21.8 (14.7‑31.9) 23.8 (15.5‑35.6) 45-day 10.4 (8.70‑12.3) 11.5 (9.62‑13.7) 13.4 (11.1‑15.9) 14.9 (12.3‑17.9) 17.0 (13.5‑21.3) 18.6 (14.4‑23.9) 20.3 (15.0‑27.0) 21.9 (15.4‑30.5) 24.1 (16.2‑35.0) 25.8 (16.8‑38.4) 60-day 12.1 (10.2‑14.3) 13.3 (11.1‑15.7) 15.3 (12.7‑18.1) 16.9 (14.0‑20.2) 19.1 (15.2‑23.8) 20.8 (16.1‑26.6) 22.5 (16.7‑29.8) 24.1 (17.1‑33.5) 26.2 (17.7‑37.9) 27.7 (18.1‑41.2) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequencyestimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical PRD-1 PWQU-1 Routing Diagram for 210116 - INLETPrepared by R Levesque Associates, Printed 12/8/2023 HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Subcat Reach Pond Link Type III 24-hr 100-Year Rainfall=7.92"210116 - INLET Printed 12/8/2023Prepared by R Levesque Associates Page 2HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Summary for Subcatchment PRD-1: Runoff = 0.6 cfs @ 12.08 hrs, Volume= 2,267 cf, Depth= 7.38" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 100-Year Rainfall=7.92" Area (sf) CN Description 394 74 >75% Grass cover, Good, HSG C 171 98 Paved parking, HSG C 3,123 98 Roofs, HSG C 3,687 Weighted Average 394 74 10.69% Pervious Area 3,293 98 89.31% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment PWQU-1: Runoff = 1.2 cfs @ 12.08 hrs, Volume= 4,474 cf, Depth= 7.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-48.00 hrs, dt= 0.03 hrs Type III 24-hr 100-Year Rainfall=7.92" Area (sf) CN Description 500 74 >75% Grass cover, Good, HSG C 6,674 98 Paved parking, HSG C 1 98 Roofs, HSG C 7,175 Weighted Average 500 74 6.97% Pervious Area 6,675 98 93.03% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, 0 SF 10,283 SF 10,283 SF 9,968 SF Total New Impervious Area Total Existing Impervious Area Total Proposed Impervious Area Total Impervious Area Tributary to Basins *Impervious Area tributary to recharge facilities must be greater than 65% Type III 24-hr 100-Year Rainfall=7.92"210116 - POST Printed 12/6/2023Prepared by R Levesque Associates HydroCAD® 10.20-2b s/n 02175 © 2021 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: Subsurface Infiltration Basin (continued) Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 251.12 1,573 3,065 251.13 1,573 3,072 251.14 1,573 3,078 251.15 1,573 3,084 251.16 1,573 3,090 251.17 1,573 3,097 251.18 1,573 3,103 251.19 1,573 3,109 251.20 1,573 3,116 251.21 1,573 3,122 251.22 1,573 3,128 251.23 1,573 3,135 251.24 1,573 3,141 251.25 1,573 3,147 251.26 1,573 3,153 251.27 1,573 3,160 251.28 1,573 3,166 251.29 1,573 3,172 251.30 1,573 3,179 251.31 1,573 3,185 251.32 1,573 3,191 251.33 1,573 3,197 251.34 1,573 3,204 251.35 1,573 3,210 251.36 1,573 3,216 251.37 1,573 3,223 251.38 1,573 3,229 251.39 1,573 3,235 251.40 1,573 3,241 251.41 1,573 3,248 251.42 1,573 3,254 251.43 1,573 3,260 251.44 1,573 3,267 251.45 1,573 3,273 251.46 1,573 3,279 251.47 1,573 3,286 251.48 1,573 3,292 251.49 1,573 3,298 251.50 1,573 3,304 MassDEP Q Rate - Sept. 10, 2013 - Page 4 Figure 2: For First ½-inch of Runoff, Table of qu values for Ia/P Curve = 0.0.058, listed by tc, for Type III Storm Distribution Tc qu Tc qu Tc qu Tc qu (Hours) (csm/in) (Hours) (csm/in) (Hours) (csm/in) (Hours) (csm/in) 0.01 821 1.8 246 5.3 116 8.8 77 0.03 821 1.9 238 5.4 115 8.9 76 0.05 813 2 230 5.5 113 9 76 0.067 794 2.1 223 5.6 112 9.1 75 0.083 773 2.2 217 5.7 110 9.2 74 0.1 752 2.3 211 5.8 109 9.3 74 0.116 733 2.4 205 5.9 107 9.4 73 0.133 713 2.5 200 6 106 9.5 72 0.15 694 2.6 194 6.1 104 9.6 72 0.167 677 2.7 190 6.2 103 9.7 71 0.183 662 2.8 185 6.3 102 9.8 70 0.2 646 2.9 181 6.4 100 9.9 70 0.217 632 3 176 6.5 99 10 69 0.233 619 3.1 173 6.6 98 0.25 606 3.2 169 6.7 97 0.3 572 3.3 165 6.8 96 0.333 552 3.4 162 6.9 94 0.35 542 3.5 158 7 93 0.4 516 3.6 155 7.1 92 0.416 508 3.7 152 7.2 91 0.5 472 3.8 149 7.3 90 0.583 443 3.9 147 7.4 89 0.6 437 4 144 7.5 88 0.667 417 4.1 141 7.6 87 0.7 408 4.2 139 7.7 86 0.8 383 4.3 136 7.8 85 0.9 361 4.4 134 7.9 84 1 342 4.5 132 8 84 1.1 325 4.6 130 8.1 83 1.2 311 4.7 128 8.2 82 1.3 297 4.8 126 8.3 81 1.4 285 4.9 124 8.4 80 1.5 274 5 122 8.5 79 1.6 264 5.1 120 8.6 79 1.7 254 5.2 118 8.7 78 Barracuda® Max The Barracuda Max is market-changing stormwater quality technology. This high-performance vortex hydrodynamic separator is designed to remove total suspended solids in order to protect our precious receiving waters. The Barracuda Max is also an outstanding value that offers multiple pipe configurations, and quick installation. The “Max” version of the Barracuda is built on the base platform of the original ADS Barracuda with improved removal efficiencies and installation components. Features • Single manhole design • No elevation loss between the inlet and outlet • Variable inlet/outlet angle configurations (not just 180 degree orientation) • Internal bypass for inline installation (where applicable) • Revolutionary, patent pending “teeth” mitigate turbulence in the sump area to prevent resuspension of captured contaminants • Available with grated drop inlet configuration • Available with trash and/or oil capture add-ons Benefits • Internal components are in stock for quick delivery • The S3, S4, S6, and S8 can be installed in a standard 36” (900 mm), 48” (1200 m), 72” (1800 m), and 96” (2400 m) precast manhole, respectively • The S3 & S4 can be provided factory installed within a 36” (900 mm) and 48” (1200 mm) ADS HP manhole and delivered to the jobsite • The Barracuda Max “teeth” and deflector plate apparatus are fabricated and designed for quick and easy field assembly • Designed for easy maintenance using a vacuum truck or similar equipment. • Inspection and maintenance are performed from the surface with no confined space entry Barrucuda Specification Materials and Design • Concrete Structures: Designed for H-20 traffic loading and applicable soil loads or as otherwise determined by a Licensed Professional Engineer. The materials and structural design of the devices shall be per ASTM C857 and ASTM C858. • 36” (900 mm) and 48” (1200 mm) HP Manhole Structures: Made from an impact modified copolymer polypropylene meeting the material requirements of ASTM F2764. The eccentric cone reducer shall be manufactured from polyethylene material meeting ASTM D3350 cell class 213320C. Gaskets shall be made of material meeting the requirements of ASTM F477. • Separator internals shall be substantially constructed of stainless steel, polyethylene or other thermoplastic material approved by the manufacturer. Performance • The stormwater treatment unit shall be an inline unit capable of conveying 100% of the design peak flow. If peak flow rates exceed maximum hydraulic rate, the unit shall be installed offline. • The Barracuda Max unit shall be designed to remove at least 80% of the suspended solids on an annual aggregate removal basis. Said removal shall be based on full-scale third party testing using OK-110 media gradation or equivalent and 300 mg/L influent concentration. Said full scale testing shall have included sediment capture based on actual total mass collected by the stormwater treatment unit. - OR - The Barracuda Max unit shall be designed to remove at least 50% of TSS using a media mix with d50=75 micron and 200 mg/L influent concentration. - OR - The Barracuda Max unit shall be designed to remove at least 50% of TSS per current NJDEP/NJCAT HDS protocol. • The stormwater treatment unit internals shall consist of (1) separator cone assembly, and (1) sump assembly, which includes the “teeth”. Installation Installation of the stormwater treatment unit(s) shall be performed per manufacturer’s installation instructions. Such instructions can be obtained by calling Advanced Drainage Systems at 800-821-6710 or by logging on to www.adspipe.com. Barracuda Max Model Manhole Diameter OK-110 (80% removal)Pretreatment for Infiltration1 S3 36” (900 mm)0.86 CFS (24.1 L/s)1.65 CFS (46.7 L/s) S4 48” (1200 mm)1.52 CFS (43.0 L/s)2.94 CFS (83.3 L/s) S6 72” (1800 mm)3.42 CFS (96.8 L/s)6.62 CFS (187.5 L/s) S8 96” (2400 mm)6.08 CFS (172.2 L/s)11.76 CFS (333.0 L/s) ADS “Terms and Conditions of Sale” are available on the website, www.ads-pipe.com . The ADS logo, Barracuda logo, and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. © 2022 Advanced Drainage Systems, Inc. 4/22 CS adspipe.com 800-821-6710 ADS N-12® ST IB Pipe (per ASTM F2648) * Peak bypass flows are dependent on final design 1 50% removal of OK-110. 1 April 28, 2021 Daniel J. Figola, P.E. Director of Sustainability Development Advanced Drainage Systems, Inc. 1030 Deer Hollow Drive Mt. Airy, MD 21771 Re: MTD Lab Certification BarracudaTM MAX Hydrodynamic Separator Stormwater Treatment Device On-line Installation TSS Removal Rate 50% Dear Mr. Figola: The Stormwater Management rules under N.J.A.C. 7:8-5.5(b) and 5.7(c) allow the use of manufactured treatment devices (MTDs) for compliance with the design and performance standards at N.J.A.C. 7:8-5 if the pollutant removal rates have been verified by the New Jersey Corporation for Advanced Technology (NJCAT) and have been certified by the New Jersey Department of Environmental Protection (NJDEP). Advanced Drainage Systems, Inc. (ADS) has requested an MTD Laboratory Certification for the BarracudaTM MAX Hydrodynamic Separator stormwater treatment system (BarracudaTM MAX). The project falls under the “Procedure for Obtaining Verification of a Stormwater Manufactured Treatment Device from New Jersey Corporation for Advance Technology” dated January 25, 2013. The applicable protocol is the “New Jersey Laboratory Testing Protocol to Assess Total Suspended Solids Removal by a Hydrodynamic Sedimentation Manufactured Treatment Device” dated January 25, 2013. NJCAT verification documents submitted to the NJDEP indicate that the requirements of the aforementioned protocol have been met or exceeded. The NJCAT letter also included a recommended certification TSS removal rate and the required maintenance plan. The NJCAT Verification Report with the Verification Appendix (dated April 2021) for this device is published online at http://www.njcat.org/verification-process/technology-verification-database.html. New Jersey is an Equal Opportunity Employer Printed on Recycled Paper and Recyclable DEPARTMENT OF ENVIRONMENTAL PROTECTION PHILIP D. MURPHY Governor SHAWN M. LATOURETTE Acting Commissioner SHEILA Y. OLIVER Lt. Governor Bureau of NJPDES Stormwater Permitting & Water Quality Management Division of Watershed Protection and Restoration 401-02BPost Office Box 420 Trenton, New Jersey 08625-0420 609-633-7021 Fax: 609-777-0432 j /d /d /b h 2 The NJDEP certifies the use of the BarracudaTM MAX stormwater treatment system at a TSS removal rate of 50% when designed, operated, and maintained in accordance with the information provided in the Verification Appendix and the following conditions: 1. The maximum treatment flow rate (MTFR) for the manufactured treatment device (MTD) is calculated using the New Jersey Water Quality Design Storm (1.25 inches in 2 hrs) in N.J.A.C. 7:8-5.5. 2. The BarracudaTM MAX shall be installed using the same configuration reviewed by NJCAT and shall be sized in accordance with the criteria specified in item 6 below. 3. This BarracudaTM MAX cannot be used in series with another MTD or a media filter (such as a sand filter) to achieve an enhanced removal rate for total suspended solids (TSS) removal under N.J.A.C. 7:8-5.5. 4. Additional design criteria for MTDs can be found in Chapter 11.3 of the New Jersey Stormwater Best Management Practices (NJ Stormwater BMP) Manual, which can be found online at www.njstormwater.org. 5. The maintenance plan for a site using this device shall incorporate, at a minimum, the maintenance requirements for the BarracudaTM MAX. A copy of the maintenance plan is attached to this certification. However, it is recommended to review the maintenance website at https://assets.ads-pipe.com/m/2c834056a5a22888/original/Barracuda-Maintenance-Guide-MG1-01.pdf for any changes to the maintenance requirements. 6. Sizing Requirement: The example on the following page demonstrates the sizing procedure for the BarracudaTM MAX: 3 Example: A 0.25-acre impervious site is to be treated to 50% TSS removal using an BarracudaTM MAX treatment unit. The impervious site runoff (Q) based on the New Jersey Water Quality Design Storm was determined to be 0.79 cfs. Maximum Treatment Flow Rate (MTFR) Evaluation: The site runoff (Q) was based on the following: time of concentration = 10 minutes i = 3.2 in/hr (page 74, Fig. 5-16 of the NJ Stormwater BMP Manual) c = 0.99 (runoff coefficient for impervious) Q = ciA = 0.99 x 3.2 x 0.25 = 0.79 cfs Given the site runoff is 0.79 cfs and based on Table A-1 below, the BarracudaTM MAX Model S3 with an MTFR of 0.85 cfs would be the smallest model that could be used for this site to remove 50% of the TSS from the impervious area without exceeding the MTFR. The sizing table corresponding to the available system models is noted below. Additional specifications regarding each model can be found in the NJCAT Technology Verification Appendix under Tables A-1 and A-2. Table A-1 BarracudaTM MAX HDS Models and Associated MTFRs Model Manhole Diameter (ft) Maximum Treatment Flow Rate (cfs) 50% Maximum Sediment Storage Area Volume (ft3) Barracuda MAX S3 3 0.85 5.89 Barracuda MAX S4 4 1.52 10.47 Barracuda MAX S5 5 2.37 16.36 Barracuda MAX S6 6 3.40 23.56 Barracuda MAX S8 8 6.08 41.89 Barracuda MAX S10 10 9.48 65.45 A detailed maintenance plan is mandatory for any project with a stormwater BMP subject to the Stormwater Management rules under N.J.A.C. 7:8. The plan must include all of the items identified in the Maintenance requirements section of the Stormwater Management rules under N.J.A.C. 7:8-5.8. Such items include, but are not limited to, the list of inspection and maintenance equipment and tools, specific corrective and preventative maintenance tasks, indication of problems in the system, and training of maintenance personnel. Additional information can be found in Chapter 8: Maintenance and Retrofit of Stormwater Management Measures. 4 If you have any questions regarding the above information, please contact Lisa Schaefer of my office at lisa.schaefer@dep.nj.gov. Sincerely, Gabriel Mahon, Chief Bureau of NJPDES Stormwater Permitting & Water Quality Management Attachment: Maintenance Plan cc: Chron File Richard Magee, NJCAT Changi Wu, NJDEP-BFHSE Madhu Guru, NJDEP - BFHSE One of Barracuda’s advantages is the ease of maintenance. Like any system that collects pollutants, the Barracuda must be maintained for continued effectiveness. Maintenance is a simple procedure performed using a vacuum truck or similar equipment. The systems were designed to minimize the volume of water removed during routine maintenance, reducing disposal costs. Contractors can access the pollutants stored in the manhole through the manhole cover. This allows them to gain vacuum hose access to the bottom of the manhole to remove sediment and trash. There is no confined space entry necessary for inspection or maintenance. The entire maintenance procedure typically takes 2 to 4 hours, depending on the system’s size, the captured material, and the vacuum truck’s capacity. Local regulations may apply to the maintenance procedure. Safe and legal disposal of pollutants is the responsibility of the maintenance contractor. Maintenance should be performed only by a qualified contractor. Inspection and Cleaning Cycle Periodic inspection is needed to determine the need for and frequency of maintenance. You should begin inspecting as soon as construction is complete and then on an annual basis. Typically, the system needs to be cleaned every 1-3 years. Excessive oils, fuels or sediments may reduce the maintenance cycle. Periodic inspection is important. Determining When to Clean To determine the sediment depth, the maintenance contractor should lower a stadia rod into the manhole until it contacts the top of the captured sediment and mark that spot on the rod. Then push the probe through to the bottom of the sump and mark that spot to determine sediment depth. Maintenance should occur when the sediment has reached the levels indicated in the Storage Capacity Chart. adspipe.com 1-800-821-6710 Barracuda Storage Capacities Model Manhole Diameter in. (mm) Total System Volume Gallons (Liters) Treatment Chamber Capacity Gallons (Liters) Standard Sediment Capacity (20” depth) Yards3 (meters3) NJDEP Sediment Capacity (50% of standard depth) Yards3 (meters3) S3 36 (900) 264 (999) 212 (803) 0.44 (0.34) 0.22 (0.17) S4 48 (1200) 665 (2517) 564 (2135) 0.78 (0.60) 0.39 (0.30) S5 60 (1500) 1040 (3937) 881 (3335) 1.21 (0.93) 0.61 (0.47) S6 72 (1800) 1497 (5667) 1269 (4804) 1.75 (1.34) 0.88 (0.67) S8 96 (2400) 4196 (15884) 3835 (14517) 3.10 (2.37) 1.55 (1.19) S10 120 (3000) 7976 (30192) 7496 (28375) 4.85 (3.71) 2.43 (1.86) Maintenance Instructions 1. Remove the manhole cover to provide access to the pollutant storage. Pollutants are stored in the sump, below the bowl assembly visible from the surface. Access this area through the 8” (200 mm), 10” (250 mm), 15” (375 mm) or 20” (500 mm) diameter access cylinder. 2. Use a vacuum truck or other similar equipment to remove all water, debris, oils and sediment. See figure 1. 3. Use a high pressure hose to clean the manhole of all the remaining sediment and debris. Then, use the vacuum truck to remove the water. 4. Fill the cleaned manhole with water until the level reaches the invert of the outlet pipe. 5. Replace the manhole cover. 6. Dispose of the polluted water, oils, sediment and trash at an approved facility. a. Local regulations prohibit the discharge of solid material into the sanitary system. Check with the local sewer authority for authority to discharge the liquid. b. Some localities treat the pollutants as leachate. Check with local regulators about disposal requirements. c. Additional local regulations may apply to the maintenance procedure. adspipe.com 1-800-821-6710 Figure 1 ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com The ADS logo, Barracuda® and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. © 2021 Advanced Drainage Systems, Inc. MG1.01 02/21 CS 4640 TRUEMAN BLVD. HILLIARD, OH 43026 (800) 821-6710 www.ads-pipe.com 1 MG1.01 ©ADS 2017 One of the advantages of the BaySaver Barracuda is the ease of maintenance. Like any system that collects pollutants, the BaySaver Barracuda must be maintained for continued effectiveness. Maintenance is a simple procedure performed using a vacuum truck or similar equipment. The systems were designed to minimize the volume of water removed during routine maintenance, reducing disposal costs. Contractors can access the pollutants stored in the manhole through the manhole cover. This allows them to gain vacuum hose access to the bottom of the manhole to remove sediment and trash. There is no confined space entry necessary for inspection or maintenance. The entire maintenance procedure typically takes from 2 to 4 hours, depending on the size of the system, the captured material, and the capacity of the vacuum truck. Local regulations may apply to the maintenance procedure. Safe and legal disposal of pollutants is the responsibility of the maintenance contractor. Maintenance should be performed only by a qualified contractor. Inspection and Cleaning Cycle Periodic inspection is needed to determine the need for and frequency of maintenance. You should begin inspecting as soon as construction is complete and thereafter on an annual basis. Typically, the system needs to be cleaned every 1-3 years. Excessive oils, fuels or sediments may reduce the maintenance cycle. Periodic inspection is important. Determining When to Clean To determine the sediment depth, the maintenance contractor should lower a stadia rod into the manhole until it contacts the top of the captured sediment and mark that spot on the rod. Then push the probe through to the bottom of the sump and mark that spot to determine sediment depth. Maintenance should occur when the sediment has reached the levels indicated in the Storage Capacity Chart. BaySaver Barracuda Storage Capacities Model Manhole Diameter Treatment Chamber Capacity Standard Sediment Capacity (20” depth) NJDEP Sediment Capacity (50% of standard depth) S3 36” 212 gallons 0.44 cubic yards 0.22 cubic yards S4 48” 564 gallons 0.78 cubic yards 0.39 cubic yards S5 60” 881 gallons 1.21 cubic yards 0.61 cubic yards S6 72” 1269 gallons 1.75 cubic yards 0.88 cubic yards S8 96” 3835 gallons 3.10 cubic yards 1.55 cubic yards S10 120” 7496 gallons 4.85 cubic yards 2.43 cubic yards Maintenance Instructions 1. Remove the manhole cover to provide access to the pollutant storage. Pollutants are stored in the sump, below the bowl assembly visible from the surface. You’ll access this area through the 10” diameter access cylinder. Maintenance Guide BaySaver BarracudaTM July 2017 2 4640 TRUEMAN BLVD. HILLIARD, OH 43026 (800) 821-6710 www.ads-pipe.com MG1.01 ©ADS 2017 2. Use a vacuum truck or other similar equipment to remove all water, debris, oils and sediment. See figure 1. 3. Use a high pressure hose to clean the manhole of all the remaining sediment and debris. Then, use the vacuum truck to remove the water. 4. Fill the cleaned manhole with water until the level reaches the invert of the outlet pipe. 5. Replace the manhole cover. 6. Dispose of the polluted water, oils, sediment and trash at an approved facility. • Local regulations prohibit the discharge of solid material into the sanitary system. Check with the local sewer authority for authority to discharge the liquid. • Some localities treat the pollutants as leachate. Check with local regulators about disposal requirements. • Additional local regulations may apply to the maintenance procedure. Figure 1 One of Barracuda’s advantages is the ease of maintenance. Like any system that collects pollutants, the Barracuda must be maintained for continued effectiveness. Maintenance is a simple procedure performed using a vacuum truck or similar equipment. The systems were designed to minimize the volume of water removed during routine maintenance, reducing disposal costs. Contractors can access the pollutants stored in the manhole through the manhole cover. This allows them to gain vacuum hose access to the bottom of the manhole to remove sediment and trash. There is no confined space entry necessary for inspection or maintenance. The entire maintenance procedure typically takes 2 to 4 hours, depending on the system’s size, the captured material, and the vacuum truck’s capacity. Local regulations may apply to the maintenance procedure. Safe and legal disposal of pollutants is the responsibility of the maintenance contractor. Maintenance should be performed only by a qualified contractor. Inspection and Cleaning Cycle Periodic inspection is needed to determine the need for and frequency of maintenance. You should begin inspecting as soon as construction is complete and then on an annual basis. Typically, the system needs to be cleaned every 1-3 years. Excessive oils, fuels or sediments may reduce the maintenance cycle. Periodic inspection is important. Determining When to Clean To determine the sediment depth, the maintenance contractor should lower a stadia rod into the manhole until it contacts the top of the captured sediment and mark that spot on the rod. Then push the probe through to the bottom of the sump and mark that spot to determine sediment depth. Maintenance should occur when the sediment has reached the levels indicated in the Storage Capacity Chart. adspipe.com 1-800-821-6710 Barracuda Storage Capacities Model Manhole Diameter in. (mm) Total System Volume Gallons (Liters) Treatment Chamber Capacity Gallons (Liters) Standard Sediment Capacity (20” depth) Yards3 (meters3) NJDEP Sediment Capacity (50% of standard depth) Yards3 (meters3) S3 36 (900) 264 (999) 212 (803) 0.44 (0.34) 0.22 (0.17) S4 48 (1200) 665 (2517) 564 (2135) 0.78 (0.60) 0.39 (0.30) S6 72 (1800) 1497 (5667) 1269 (4804) 1.75 (1.34) 0.88 (0.67) S8 96 (2400) 4196 (15884) 3835 (14517) 3.10 (2.37) 1.55 (1.19) Maintenance Instructions 1. Remove the manhole cover to provide access to the pollutant storage. Pollutants are stored in the sump, below the bowl assembly visible from the surface. Access this area through the 8” (200 mm), 10” (250 mm), 15” (375 mm) or 20” (500 mm) diameter access cylinder. 2. Use a vacuum truck or other similar equipment to remove all water, debris, oils and sediment. See figure 1. 3. Use a high pressure hose to clean the manhole of all the remaining sediment and debris. Then, use the vacuum truck to remove the water. 4. Fill the cleaned manhole with water until the level reaches the invert of the outlet pipe. 5. Replace the manhole cover. 6. Dispose of the polluted water, oils, sediment and trash at an approved facility. a. Local regulations prohibit the discharge of solid material into the sanitary system. Check with the local sewer authority for authority to discharge the liquid. b. Some localities treat the pollutants as leachate. Check with local regulators about disposal requirements. c. Additional local regulations may apply to the maintenance procedure. adspipe.com 1-800-821-6710 Figure 1 ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com The ADS logo, Barracuda® and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. © 2022 Advanced Drainage Systems, Inc. MG1.01 08/22 CS          StormTech SC-740 Chamber Designed to meet the most stringent industry performance standards for superior structural integrity while providing designers with a cost-effective method to save valuable land and protect water resources. The StormTech system is designed primarily to be used under parking lots thus maximizing land usage for commercial and municipal applications. 90.7" (2300 mm) 51.0" (1295 mm) 85.4" (2170 mm) INSTALLED ACCEPTS4"(100SCH 40 PIPE FOR OPTIONALINSPECTION PORT 30.0"(762 mm) 8"(203 mm) 24" (610 mm) DIA. MAX SC-740 End Cap StormTech SC-740 Chamber (not to scale) Nominal Chamber Specifications Size (L x W x H) 85.4" x 51.0" x 30.0" (2170 x 1295 x 762 mm) Chamber Storage 45.9 ft 3 (1.30 m 3) Minimum Installed Storage* 74.9 ft 3 (2.12 m 3) Weight 74.0 lbs (33.6 kg) Shipping 30 chambers/pallet 60 end caps/pallet 12 pallets/truck SC-740 Chamber INCREASE COVER TO 24"(610 MM) FOR UNPAVED INSTALLATION WHERE RUTTING FROM VEHICLES MAY OCCUR, 30" (762 mm) SC-740 DEPTH OF STONE TOBEDETERMINEDBYDESIGN ENGINEER*6"(150mm) MIN. 12" MIN. (305 mm) TYP. 6" (150 mm) MIN. 18" (460 mm) MIN. 96"(2440 mm) MAX. DESIGNENGINEER ISRESPONSIBLEFORENSURINGTHEREQUIREDBEARINGCAPACITYOFSUBGRADESOILS* 51" (1295 mm) MIN.6"(150 mm) MIN. PAVEMENT 3/4-2"(19-50 mm)CLEAN,CRUSHED,ANGULAR STONE SC-740 CHAMBER SC-740 END CAPADS601GEOTEXTILEOREQUAL THE INSTALLED CHAMBER SYSTEM SHALL PROVIDE THE LOAD FACTORS SPECIFIED IN THE AASHTO LRFD BRIDGE DESIGNSPECIFICATIONS SECTION 12.12 FOREARTHANDLIVELOADS,WITH CONSIDERATION FOR IMPACT AND MULTIPLE VEHICLE PRESENCES.GRANULARWELLGRADEDSOIL/AGGREGATE MIXTURES,<35%FINES. COMPACT IN 6"(150mm)LIFTSTO 95% STANDARD PROCTOR DENSITY. SEE THETABLE OF ACCEPTABLE FILL MATERIALS. CHAMBERS SHALL MEET ASTM F2922-12 “STANDARD SPECIFICATION FOR POLYETHYLENE (PE) CORRUGATEDWALL STORMWATER COLLECTION CHAMBERS.” THISCROSS SECTIONDETAILS THE REQUIREMENTS NECESSARY TO SATISFY THE LOAD FACTORS SPECIFIED IN THE AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS SECTION12.12 FOR EARTH AND LIVE LOADS USING STORMTECH CHAMBERS Typical Cross Section Detail (not to scale) MADE IN THE U.S.A. Printed on recycled paperPrinted in U.S.A. © Copyright. All rights reserved. StormTech LLC, 2007 S16-090508 20BeaverRoad,Suite104 Wethersfield Connecticut 06109 860.529.8188 888.892.2694 fax866.328.8401 fax860-529-8040 www.stormtech.com STANDARD LIMITED WARRANTY OF STORMTECH LLC ("STORMTECH"): PRODUCTS (A) This Limited Warranty applies solely to the StormTech chambers and endplates manufactured byStormTechandsoldtotheoriginalpurchaser(the“Purchaser”).Thechambersandendplates are collectively referred to as the “Products.” (B) The structural integrity of the Products, when installed strictly in accordance with StormTech's written installation instructions at the time of installation, are warranted to the Purchaser against defective materials and workmanship for one (1) year from the date of purchase. Should a de- fect appear in the Limited Warranty period, the Purchaser shall provide StormTech with written notice of the alleged defect at StormTech’s corporate headquarters within ten (10) days of the discovery of the defect. The notice shall describe the alleged defect in reasonable detail. StormTech agrees to supply replacements for those Products determined by StormTech to be defective and covered by this Limited Warranty. The supply of replacement products is the sole remedy of the Purchaser for breaches of this Limited Warranty. StormTech’s liability specifically excludes the cost of removal and/or installation of the Products. (C)THIS LIMITED WARRANTY IS EXCLUSIVE. THERE ARE NO OTHER WARRANTIES WITH RESPECT TO THE PRODUCTS, INCLUDING NO IMPLIED WARRANTIES OF MERCHANT-ABILITY OR OF FITNESS FOR A PARTICULAR PURPOSE. (D) This Limited Warranty only applies to the Products when the Products are installed in a single layer. UNDER NO CIRCUMSTANCES, SHALL THE PRODUCTS BE INSTALLED IN A MULTI-LAYER CONFIGURATION. (E) No representative of StormTech has the authority to change this Limited Warranty in any manner or to extend this Limited Warranty. This Limited Warranty does not apply to any person other than to the Purchaser. (F) Under no circumstances shall StormTech be liable to the Purchaser or to any third party for prod- uct liability claims; claims arising from the design, shipment, or installation of the Products, or the cost of other goods or services related to the purchase and installation of the Products. For this Limited Warranty to apply, the Products must be installed in accordance with all site condi- tions required by state and local codes; all other applicable laws; and StormTech’s written in- stallation instructions. (G)THE LIMITED WARRANTY DOES NOT EXTEND TO INCIDENTAL, CONSEQUENTIAL, SPE- CIAL OR INDIRECT DAMAGES. STORMTECH SHALL NOT BE LIABLE FOR PENALTIES OR LIQUIDATED DAMAGES, INCLUDING LOSS OF PRODUCTION AND PROFITS; LABOR AND MATERIALS; OVERHEAD COSTS; OR OTHER LOSS OR EXPENSE INCURRED BY THE PURCHASER OR ANY THIRD PARTY. SPECIFICALLY EXCLUDED FROM LIMITED WAR- RANTY COVERAGE ARE DAMAGE TO THE PRODUCTS ARISING FROM ORDINARY WEAR AND TEAR; ALTERATION, ACCIDENT, MISUSE, ABUSE OR NEGLECT; THE PRODUCTS BEING SUBJECTED TO VEHICLE TRAFFIC OR OTHER CONDITIONS WHICH ARE NOT PERMITTED BY STORMTECH’S WRITTEN SPECIFICATIONS OR INSTALLATION INSTRUC- TIONS; FAILURE TO MAINTAIN THE MINIMUM GROUND COVERS SET FORTH IN THE INSTALLATION INSTRUCTIONS; THE PLACEMENT OF IMPROPER MATERIALS INTO THE PRODUCTS; FAILURE OF THE PRODUCTS DUE TO IMPROPER SITING OR IMPROPER SIZING; OR ANY OTHER EVENT NOT CAUSED BY STORMTECH. THIS LIMITED WAR- RANTY REPRESENTS STORMTECH’S SOLE LIABILITY TO THE PURCHASER FOR CLAIMS RELATED TO THE PRODUCTS, WHETHER THE CLAIM IS BASED UPON CON- TRACT, TORT, OR OTHER LEGAL THEORY. Amount of Stone Per Chamber Note: Volumes are in cubic yards (cubic meters) per chamber. Assumes 6" (150 mm) of separation between chamber rows and 18" (460 mm) of cover. The volume of excavation will vary as the depth of the cover increases. Volume of Excavation Per Chamber Stone Foundation Depth 6" (150 mm) 12" (305 mm) 18" (460 mm) StormTech SC-740 5.5 (4.2) 6.2 (4.7) 6.8 (5.2) Note: Storage volumes are in cubic feet per chamber. Assumes 40% porosity for the stone plus the chamber volume. Storage Volume Per Chamber Bare Chamber and Stone Chamber Stone Foundation Depth Storage in. (mm) ft3 (m3)6(150) 12(305) 18(460) StormTech SC-740 45.9 (1.3) 74.9 (2.1) 81.7 (2.3) 88.4 (2.5) Note: Assumes 6" (150 mm) of stone above, and between chambers. Stone Foundation Depth ENGLISH TONS (CUBIC YARDS)6" 12" 18" StormTech SC-740 3.8 (2.8 yd 3)4.6 (3.3 yd 3)5.5 (3.9 yd 3) METRIC KILOGRAMS (METER 3)150 mm 305 mm 460 mm StormTech SC-740 3450 (2.1 m 3)4170(2.5m3)4490(3.0m3) 42(1067) 45.90(1.300) 74.90(2.121) 41 (1041) 45.90 (1.300) 73.77 (2.089) 40 (1016) 45.90 (1.300) 72.64 (2.057) 39 (991) 45.90 (1.300) 71.52 (2.025) 38 (965) 45.90 (1.300) 70.39 (1.993) 37 (948) 45.90 (1.300) 69.26 (1.961) 36 (914) 45.90 (1.300) 68.14 (1.929) 35 (889) 45.85 (1.298) 66.98 (1.897) 34 (864) 45.69 (1.294) 65.75 (1.862) 33 (838) 45.41 (1.286) 64.46 (1.825) 32 (813) 44.81 (1.269) 62.97 (1.783) 31 (787) 44.01 (1.246) 61.36 (1.737) 30 (762) 43.06 (1.219) 59.66 (1.689) 29 (737) 41.98 (1.189) 57.89 (1.639) 28 (711) 40.80 (1.155) 56.05 (1.587) 27 (686) 39.54 (1.120) 54.17 (1.534) 26 (660) 38.18 (1.081) 52.23 (1.479) 25 (635) 36.74 (1.040) 50.23 (1.422) 24 (610) 35.22 (0.977) 48.19 (1.365) 23 (584) 33.64 (0.953) 46.11 (1.306) 22 (559) 31.99 (0.906) 44.00 (1.246) 21 (533) 30.29 (0.858) 41.85 (1.185) 20 (508) 28.54 (0.808) 39.67 (1.123) 19 (483) 26.74 (0.757) 37.47 (1.061) 18 (457) 24.89 (0.705) 35.23 (0.997) 17 (432) 23.00 (0.651) 32.96 (0.939) 16 (406) 21.06 (0.596) 30.68 (0.869) 15 (381) 19.09 (0.541) 28.36 (0.803) 14 (356) 17.08 (0.484) 26.03 (0.737) 13 (330) 15.04 (0.426) 23.68 (0.670) 12 (305) 12.97 (0.367) 21.31 (0.608) 11 (279) 10.87 (0.309) 18.92 (0.535) 10 (254) 8.74 (0.247) 16.51 (0.468) 9(229) 6.58(0.186) 14.09(0.399) 8(203) 4.41(0.125) 11.66(0.330) 7(178) 2.21(0.063) 9.21(0.264) 6(152) 0 6.76(0.191) 5(127) 0 5.63(0.160) 4(102) 0 4.51(0.125) 3(76) 0 3.38(0.095) 2(51) 0 2.25(0.064) 1(25) 0 1.13(0.032) Depth of Water Cumulative Total System inSystem ChamberStorage CumulativeStorage Inches (mm) Ft 3 (m3)Ft3(m3) SC-740 Cumulative Storage Volumes Per Chamber Assumes 40% Stone Porosity. Calculations are Based Upon a 6" (152 mm) Stone Base Under the Chambers. Stone Cover Note: Add 1.13 cu. ft. (0.032 m 3)ofstorageforeachadditional inch (25 mm) of stone foundation. Stone Foundation Isolator®Row O&M Manual StormTech®Chamber System for Stormwater Management Save Valuable Land and Protect Water Resources Detention • Retention • Water Quality A division of 1.1 INTRODUCTION An important component of any Stormwater Pollution Prevention Plan is inspection and maintenance. The StormTech Isolator Row is a patented technique to inexpensively enhance Total Suspended Solids (TSS) removal and provide easy access for inspection and maintenance. 1.2 THE ISOLATOR ROW The Isolator Row is a row of StormTech chambers, either SC-310, SC-310-3, SC-740, DC-780, MC-3500 or MC- 4500 models, that is surrounded with filter fabric and con- nected to a closely located manhole for easy access. The fabric-wrapped chambers pro vide for settling and filtra- tion of sediment as storm water rises in the Isolator Row and ultimately passes through the filter fabric. The open bottom chambers and perforated sidewalls (SC-310, SC- 310-3 and SC-740 models) allow storm water to flow both vertically and horizon tally out of the chambers. Sediments are cap tured in the Isolator Row protecting the storage areas of the adjacent stone and chambers from sediment accumulation. Two different fabrics are used for the Isolator Row. A woven geotextile fabric is placed between the stone and the Isolator Row chambers. The tough geo textile provides a media for storm water filtration and provides a durable surface for maintenance operations. It is also designed to prevent scour of the underlying stone and remain intact during high pressure jetting. A non-woven fabric is placed over the chambers to provide a filter media for flows passing through the perforations in the sidewall of the chamber. The non-woven fabric is not required over the DC-780, MC-3500 or MC-4500 models as these chambers do not have perforated side walls. 2 Call StormTech at 888.892.2694 or visit our website at www.stormtech.com for technical and product information. 1.0 The Isolator®Row The Isolator Row is typically designed to capture the “first flush” and offers the versatility to be sized on a vol- ume basis or flow rate basis. An upstream manhole not only provides access to the Isolator Row but typically includes a high flow weir such that storm water flowrates or volumes that exceed the capacity of the Isolator Row overtop the over flow weir and discharge through a manifold to the other chambers. The Isolator Row may also be part of a treatment train. By treating storm water prior to entry into the chamber system, the service life can be extended and pollutants such as hydrocarbons can be captured. Pre-treatment best management practices can be as simple as deep sump catch basins, oil-water separators or can be inno- vative storm water treatment devices. The design of the treatment train and selection of pretreatment devices by the design engineer is often driven by regulatory requirements. Whether pretreatment is used or not, the Isolator Row is recommended by StormTech as an effective means to minimize maintenance requirements and maintenance costs. Note: See the StormTech Design Manual for detailed information on designing inlets for a StormTech system, including the Isolator Row. ECCENTRIC HEADER MANHOLE WITH OVERFLOW WEIR STORMTECH ISOLATOR ROW OPTIONAL PRE-TREATMENT OPTIONAL ACCESS STORMTECH CHAMBERS StormTech Isolator Row with Overflow Spillway (not to scale) Looking down the Isolator Row from the manhole opening, woven geotextile is shown between the chamber and stone base. 2.0 Isolator Row Inspection/Maintenance Call StormTech at 888.892.2694 or visit our website at www.stormtech.com for technical and product information. 3 Maintenance is accomplished with the JetVac process. The JetVac process utilizes a high pressure water noz- zle to propel itself down the Isolator Row while scouring and suspending sediments. As the nozzle is retrieved, the captured pollutants are flushed back into the man- hole for vacuuming. Most sewer and pipe maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle will improve maintenance efficiency. Fixed nozzles designed for cul- verts or large diameter pipe cleaning are preferable. Rear facing jets with an effective spread of at least 45” are best. Most JetVac reels have 400 feet of hose allow- ing maintenance of an Isolator Row up to 50 chambers long. The JetVac process shall only be performed on StormTech Isolator Rows that have AASHTO class 1 woven geotextile (as specified by StormTech) over their angular base stone. 2.1 INSPECTION The frequency of Inspection and Maintenance varies by location. A routine inspection schedule needs to be established for each individual location based upon site specific variables. The type of land use (i.e. industrial, commercial, residential), anticipated pollutant load, per- cent imperviousness, climate, etc. all play a critical role in determining the actual frequency of inspection and maintenance practices. At a minimum, StormTech recommends annual inspec- tions. Initially, the Isolator Row should be inspected every 6 months for the first year of operation. For sub sequent years, the inspection should be adjusted based upon previous observation of sediment deposition. The Isolator Row incorporates a combination of standard manhole(s) and strategically located inspection ports (as needed). The inspection ports allow for easy access to the system from the surface, eliminating the need to perform a confined space entry for inspection purposes. If upon visual inspection it is found that sediment has accumulated, a stadia rod should be inserted to deter- mine the depth of sediment. When the average depth of sediment exceeds 3 inches throughout the length of the Isolator Row, clean-out should be performed. 2.2 MAINTENANCE The Isolator Row was designed to reduce the cost of periodic maintenance. By “isolating” sediments to just one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage bed. If inspection indicates the potential need for main- tenance, access is provided via a manhole(s) located on the end(s) of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a confined space entries. StormTech Isolator Row (not to scale) Examples of culvert cleaning nozzles appropriate for Isolator Row maintenance. (These are not StormTech products.) NOTE:NON-WOVEN FABRIC IS ONLY REQUIRED OVER THE INLET PIPE CONNECTION INTO THE END CAP FOR DC-780, MC-3500 AND MC-4500 CHAMBER MODELS AND IS NOT REQUIRED OVER THE ENTIRE ISOLATOR ROW. Step 1)Inspect Isolator Row for sediment A) Inspection ports (if present) i. Remove lid from floor box frame ii. Remove cap from inspection riser iii. Using a flashlight and stadia rod, measure depth of sediment and record results on maintenance log. iv. If sediment is at, or above, 3 inch depth proceed to Step 2. If not proceed to step 3. B) All Isolator Rows i. Remove cover from manhole at upstream end of Isolator Row ii. Using a flashlight, inspect down Isolator Row through outlet pipe 1.Mirrors on poles or cameras may be used to avoid a confined space entry 2.Follow OSHA regulations for confined space entry if entering manhole iii. If sediment is at or above the lower row of sidewall holes (approximately 3 inches) proceed to Step 2. If not proceed to Step 3. Step 2)Clean out Isolator Row using the JetVac process A) A fixed culvert cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable B) Apply multiple passes of JetVac until backflush water is clean C) Vacuum manhole sump as required Step 3) Replace all caps, lids and covers, record observations and actions Step 4)Inspect & clean catch basins and manholes upstream of the StormTech system ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com Advanced Drainage Systems, the ADS logo, and the green stripe are registered trademarks of Advanced Drainage Systems. Stormtech®and the Isolator®Row are registered trademarks of StormTech, Inc. Green Building Council Member logo is a registered trademark of the U.S. Green Building Council. © 2013 Advanced Drainage Systems, Inc. SO90809 02/13 3.0 Isolator Row Step By Step Maintenance Procedures 4 21) B)1) A) StormTech Isolator Row (not to scale) Stadia Rod Readings Fixed point Fixed point Sediment Date to chamber to top of Depth Observations/Actions Inspector bottom (1) sediment (2) (1) - (2) 3/15/01 6.3 ft. none New installation. Fixed point is Cl frame at grade djm 9/24/01 6.2 0.1 ft. Some grit felt sm 6/20/03 5.8 0.5 ft. Mucky feel, debris visible in manhole and in rv Isolator row, maintenance due 7/7/03 6.3 ft.0 System jetted and vacuumed djm Sample Maintenance Log 70 Inwood Road, Suite 3 Rocky Hill Connecticut 06067 860.529.8188 888.892.2694 fax 866.328.8401 www.stormtech.com Detention • Retention • Water Quality A division of One of Barracuda’s advantages is the ease of maintenance. Like any system that collects pollutants, the Barracuda must be maintained for continued effectiveness. Maintenance is a simple procedure performed using a vacuum truck or similar equipment. The systems were designed to minimize the volume of water removed during routine maintenance, reducing disposal costs. Contractors can access the pollutants stored in the manhole through the manhole cover. This allows them to gain vacuum hose access to the bottom of the manhole to remove sediment and trash. There is no confined space entry necessary for inspection or maintenance. The entire maintenance procedure typically takes 2 to 4 hours, depending on the system’s size, the captured material, and the vacuum truck’s capacity. Local regulations may apply to the maintenance procedure. Safe and legal disposal of pollutants is the responsibility of the maintenance contractor. Maintenance should be performed only by a qualified contractor. Inspection and Cleaning Cycle Periodic inspection is needed to determine the need for and frequency of maintenance. You should begin inspecting as soon as construction is complete and then on an annual basis. Typically, the system needs to be cleaned every 1-3 years. Excessive oils, fuels or sediments may reduce the maintenance cycle. Periodic inspection is important. Determining When to Clean To determine the sediment depth, the maintenance contractor should lower a stadia rod into the manhole until it contacts the top of the captured sediment and mark that spot on the rod. Then push the probe through to the bottom of the sump and mark that spot to determine sediment depth. Maintenance should occur when the sediment has reached the levels indicated in the Storage Capacity Chart. adspipe.com 1-800-821-6710 Barracuda Storage Capacities Model Manhole Diameter in. (mm) Total System Volume Gallons (Liters) Treatment Chamber Capacity Gallons (Liters) Standard Sediment Capacity (20” depth) Yards3 (meters3) NJDEP Sediment Capacity (50% of standard depth) Yards3 (meters3) S3 36 (900) 264 (999) 212 (803) 0.44 (0.34) 0.22 (0.17) S4 48 (1200) 665 (2517) 564 (2135) 0.78 (0.60) 0.39 (0.30) S6 72 (1800) 1497 (5667) 1269 (4804) 1.75 (1.34) 0.88 (0.67) S8 96 (2400) 4196 (15884) 3835 (14517) 3.10 (2.37) 1.55 (1.19) Maintenance Instructions 1. Remove the manhole cover to provide access to the pollutant storage. Pollutants are stored in the sump, below the bowl assembly visible from the surface. Access this area through the 8” (200 mm), 10” (250 mm), 15” (375 mm) or 20” (500 mm) diameter access cylinder. 2. Use a vacuum truck or other similar equipment to remove all water, debris, oils and sediment. See figure 1. 3. Use a high pressure hose to clean the manhole of all the remaining sediment and debris. Then, use the vacuum truck to remove the water. 4. Fill the cleaned manhole with water until the level reaches the invert of the outlet pipe. 5. Replace the manhole cover. 6. Dispose of the polluted water, oils, sediment and trash at an approved facility. a. Local regulations prohibit the discharge of solid material into the sanitary system. Check with the local sewer authority for authority to discharge the liquid. b. Some localities treat the pollutants as leachate. Check with local regulators about disposal requirements. c. Additional local regulations may apply to the maintenance procedure. adspipe.com 1-800-821-6710 Figure 1 ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com The ADS logo, Barracuda® and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. © 2022 Advanced Drainage Systems, Inc. MG1.01 08/22 CS