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HomeMy WebLinkAbout05/24/2019 - Drainage Report & Stormwater Management Plan - 481 Sutton Street ter r r r r Management • r L-Dr North Andover Adult Center 1 Surry Street North Andover, Massachusetts Applicant Town of North Andover Architect Catlin + Petrovick Architects PC Civil Engineer, Landscape Architect & Site Planner � � ' DeVellis Zrein Inc. CIVI ° PO Box 307 O..= Foxboro, MA 02035 t www.develliszrein.com ` May 24, 2019 1 Center • Andover, ' Drainage Report 1.0 Executive Summary 2.0 Existing Conditions Description of Contributing Area Existing Drainage Areas Soil Conditions Existing Drainage Area Summary Peak Discharge Runoff Rates 3.0 Proposed Conditions Description of Contributing Area Proposed Drainage Areas Proposed Drainage Area Summary Peak Discharge Runoff Rates Summary of Results 4.0 Methodology and Design Criteria Hydrologic Model Design Storms Time of Concentration Curve Numbers Design Criteria Rational Method 5.0 DEP Stormwater Management Standards 6.0 Operation and Maintenance Plan Appendix A-Hydrologic Calculations and Drain Pipe Calculations Hydrologic Model -Existing Conditions Existing Conditions Calculations Hydrologic Model - Proposed Conditions Proposed Conditions Calculations Appendix B—Water Quality & TSS Removal Calculations TSS Removal Calculations Infiltration Volume Calculations Appendix C—Test Pit Data Appendix D—Reduced Site Plans DeVellis Zrein, Inc. May 24,2019 2 North'Adult Center Andover, ' Drainage Report 1 . Executive Summary The Town of North Andover is proposing a new Adult Center to be located at the intersection of Surrey Drive and Sutton Street at 1 Surry Street in North Andover, Massachusetts. This project consists of the redevelopment of the property and the construction of one building with associated site improvements, parking, landscaping, patios and walkways, stormwater mitigation and underground utilities. The site currently consists of two 2-family homes on Surrey Drive and Sutton Street. There are no rivers or wetlands associated with the Site or nearby and the Site is outside of any FEMA-FIRM 100 year flood zones or Natural Heritage areas of protected wildlife or vegetation. This report addresses the drainage characteristics of the proposed redevelopment project with respect to current and future stormwater runoff. It qualifies and quantifies the drainage mitigation with respect to stormwater runoff volumes, runoff rates, and stormwater quality as well as the addressing sediment and runoff controls during and after the construction process. This project is west of a multifamily site development planned project currently being designed and permitted concurrently but separately with this project. A portion of this project will be master planned with the abutting project with respect to site improvements such as access drives and utilities. DeVellis Zrein Inc. (DZI) has analyzed the pre-development and post-development conditions of the project site and developed a stormwater management plan to mitigate the impacts resulting from this proposed project. The report addresses the stormwater maintenance protocol required to help ensure that the drainage system is maintained properly and achieve longevity and effectiveness. The proposed construction will increase the impervious surface area on-site and the stormwater management system has been designed to mitigate any increase in stormwater runoff to ensure that the post-development peak runoff rate from the site will be less than to the existing peak runoff rates. Regulations require an applicant to match the rate in which stormwater leaves the Site. The future stormwater runoff from the development area will be reduced with drainage improvements such as a closed piping system with catch basin water quality control structures, an underground stormwater infiltration/detention basin and rain gardens. The future maintenance and upkeep of the site will be the responsibility of the Town of North Andover. The stormwater design addresses ease of parking lot maintenance concerns while meeting the all of the state and town stormwater requirements and standards. Massachusetts Performance Standards and Regulations for Stormwater Management "Best Management Practices" have all been exceeded. DeVellis Zrein, Inc. May 24,2019 3 Center • Andover, ' Drainage Report The following narrative provides a description of both the existing and proposed site conditions, and the methodology for design and implementation of stormwater management systems for the project. 2. Existing Conditions The project site is approximately 1.8 acres, located at the intersection of Surrey Drive and Sutton Street at 1 Surry Street and is comprised of lots to be combined during the permitting and development process. For the purpose of this report, the Site will be described as one site. There are no Massachusetts Department of Environmental Protection (DEP) regulatory resources on site or within jurisdictional buffer limits. The site is serviced by Municipal water and sewer and there are no wells or on-site septic systems. The site will be accessed from Sutton Street through a shared drive with the abutting development and it will have an exit to Surrey Drive. The site is currently fully developed and can be generally described as residentially landscaped with two family homes, driveways, sheds, grass and trees with residential utilities. The topography is gentle sloping with a 6 foot grade change across the Site. The majority of the Site slopes from east to west towards Surrey Street with a small area sloping towards the north onto Sutton Street. The elevation ranges from approximately 164-feet(ft) at the northeast area of the Site to approximately 158 ft at the west area of the site. Description of Contributing Area The following is a brief description of the drainage area: The analysis has been prepared to identify each existing drainage area and the design has been performed to reduce pre- and post- runoff conditions to each area. The existing development area is approximately 1.8 acres and the area of effective drainage study is approximately 1.5 acres (Figure EX-1) and is categorized as with one distinct watersheds, EX-1 which is tributary to the Surrey Drive and Sutton Street closed drainage system. DZI has performed test pits throughout the site to determine subsurface conditions and current and historic high groundwater levels on the Site. For the purpose of this hydrologic analysis, the following assumptions were made: • Whenever possible, the property line and/or an arbitrary line, outside the limit of proposed work are delineated as the watershed boundary. • The total watershed area for the existing conditions is used as the comparison base for the watershed area in the proposed conditions. DeVellis Zrein, Inc. May 24,2019 4 WATERSHED LIMIT WATERSHED AREA ♦ DISCHARGE POINT `STJTTON STREET DP-1 P i, PAVEMENT It Is Cn 7 JL J Cf) ZZ 01 25' 50' 100, ;Site Planning,Civil Engineering,Landscape Architecture Job#: :Po Box 307 Sketch No. I Foxborough,MA EX Drawn by: D7 F JAZ Checked By: �508.473.4114 phone !develliszrein.com Date: 05.20.19 DeVelfis Zrein Inc. Project North Andover Scale: 1"=50 1 Title: Existing Watershed Map Adult Center NorthAndover, ' Drainage Report Soil Conditions The soils are defined by the Soil Conservation Services (SCS) Soil Survey of Essex County, Massachusetts. The site is comprised of one soil type, Type C with a small portion categorized as Urban Land. See copy of the SCS Soils Survey of Essex County at the end of this memo. The following table lists the soil designation, soil name and the soil group. Table 1-SCS Soil Types Map Soil Name Soil Group Designation 305B Paxton fine sandy loam, C 3 to 8 percent slopes 602 Urban Land none Existing Drainage Area Summary The following table summarizes the existing drainage area, including the pertinent information used for the hydrologic analysis: Existing Conditions Drainage Area -Characteristics Drainage Area Curve Tc Area (acres) Number (min.) EX-1 1.5 85 6 Peak Discharge Runoff Rates The existing peak flow rates, tributary to the drainage point, were calculated for the 2, 10, and 100-year storm events in accordance with guidelines given in DEP's Stormwater Management Policy. Results are presented in the following section of this report. Refer to Existing Watershed Plan for a delineation of the watershed areas and their respective points of concentration. DeVellis Zrein, Inc. May 24,2019 6 Hydrologic Soil Group—Essex County,Massachusetts,Northern Part (North Andover Senior Center) m F F 326120 3MI70 32622] 32e270 "u2o32" 0 M70 326420 326470 32!a520 326570 42°42'45'N 1 �,. i 42°4Z 45"N 3 wv � {{1 } _ sr„ R I i. y i .�� lt��iF 1 • fS } Soil Map may not�b�valid at this scaly. 42°42'35'N � 42°42'35"N 326120 325170 326220 326270 325MO 323M 325420 326470 325520 326570 3 B. F Map Scale:1:2,280 iP printed on A landscape(11"x 8.S")sheet. N Meters 0 30 60 120 1;� Feet 0 100 2W 400 6) k Map projection:Web Mercator Comer coordinates:WGS84 Edge tics:UTM Zone 19N WGS84 USDA Natural Resources Web Soil Survey 5/18/2019 Conservation Service National Cooperative Soil Survey Page 1 of 4 Hydrologic Soil Group—Essex County,Massachusetts,Northern Part (North Andover Senior Center) MAP LEGEND MAP INFORMATION Area of Interest(A01) E3 C The soil surveys that comprise your A01 were mapped at Area of Interest(AOI) C/D 1:15,800. Soils D Warning:Soil Map may not be valid at this scale. Soil Rating Polygons A ® Not rated or not available Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil A/D water Features line placement.The maps do not show the small areas of Streams and Canals contrasting soils that could have been shown at a more detailed B Transportation scale. Q B/D ;-4-4 Rails Please rely on the bar scale on each map sheet for map 0 C Interstate Highways measurements. 0 C/D US Routes Source of Map: Natural Resources Conservation Service D Web Soil Survey URL: Major Roads Coordinate System: Web Mercator(EPSG:3857) 0 Not rated or not available Local Roads Maps from the Web Soil Survey are based on the Web Mercator Soil Rating Lines Background projection,which preserves direction and shape but distorts A distance and area.A projection that preserves area,such as the IM Aerial Photography Albers equal-area conic projection,should be used if more A/D accurate calculations of distance or area are required. B This product is generated from the USDA-NRCS certified data as B/D of the version date(s)listed below. C Soil Survey Area: Essex County,Massachusetts,Northern Part Survey Area Data: Version 14,Sep 7,2018 C/D Soil map units are labeled(as space allows)for map scales D 1:50,000 or larger. Not rated or not available Date(s)aerial images were photographed: Aug 29,2014—Sep Soil Rating Points 19,2014 A The orthophoto or other base map on which the soil lines were El compiled and digitized probably differs from the background A/D imagery displayed on these maps.As a result,some minor 13 B shifting of map unit boundaries may be evident. 13 B/D USDA Natural Resources Web Soil Survey 5/18/2019 Conservation Service National Cooperative Soil Survey Page 2 of 4 Hydrologic Soil Group—Essex County,Massachusetts,Northern Part North Andover Senior Center Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 305B Paxton fine sandy loam, C 15.3 65.3% 3 to 8 percent slopes 305C Paxton fine sandy loam, C 1.0 4.4% 8 to 15 percent slopes 310B Woodbridge fine sandy C/D 1.8 7.7% loam,3 to 8 percent slopes 421 B Canton fine sandy loam, B 0.0 0.0% 0 to 8 percent slopes, very stony 602 I Urban land 4.7 20.1% 651 Udorthents,smoothed A 0.6 2.5% Totals for Area of Interest 23.5 100.0% usak Natural Resources Web Soil Survey 5/18/2019 NiO Conservation Service National Cooperative Soil Survey Page 3 of 4 9 Hydrologic Soil Group—Essex County,Massachusetts, Northern Part North Andover Senior Center Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate(low runoff potential)when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate(high runoff potential)when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher USDA Natural Resources Web Soil Survey 5/18/2019 Conservation Service National Cooperative Soil Survey Page 4 of 4 10 Adult • Andover, ' Drainage Report 3. Proposed Conditions The proposed project consists of the construction of a two-story Adult Center building with associated access drives, parking, a pervious patio and walkways, rain gardens, landscaping, utility services and drainage improvements. When impervious surfaces such as pavement and roof top are proposed, there will be an increase in stormwater runoff if mitigation is not provided. A stormwater management system is required to maintain the characteristics of the existing watersheds to the extent practicable. Meeting current conditions are the requirement. Runoff rates at the discharge point are required to be maintained to existing conditions by temporarily holding runoff and slowly releasing it off site to meet existing peak flow rates. The stormwater objectives of this project are summarized as follows: 1. Decrease the rate of runoff by providing stormwater retention 2. Provide a safe and environmentally sustainable solution to infiltrate stormwater on site such as rain gardens and separated systems. 3. Separate pavement runoff from roof runoff 4. Incorporate a stormwater system into aesthetically pleasing passive open space use 5. Provide a system that has longevity with minimal expense with a well understood maintenance protocol 6. Exceed proper engineering standards of North Andover's DPW the DEP The proposed development site will consist of two distinct watershed areas, PR-1A and PR-1 B (Figure PR). Drainage area PR-1A is approximately 0.5 acres and drain into rain gardens or a closed drainage system and enter into the onsite underground infiltration/detention system below the parking lot. Drainage area PR-1 B is approximately 1.0 acres and will be collected into the closed drainage system. These two areas will be combined to then connect to the Surrey Drive underground drainage system. The peak rates of runoff will not exceed the existing rates of runoff. Detailed description of each contributing area is provided below: Drainage Area PR-1A Drainage Area PR-1A encompasses the entire roof and perimeter areas surrounding the building with the following mitigation items. Roof Runoff: The building's roof is pitched to the sides and collected with piping. Stormwater runoff is considered clean and suitable for direct infiltration into the ground to provide groundwater recharge. The roof runoff will be collected and either piped directly to an on-site "rain garden" located behind the building aside the pervious. The raingarden will DeVellis Zrein, Inc. May 24,2019 11 ��Oat Ce ter NorthAndover, Drainage Report fill during rain events and drain dry through infiltration with an overflow provided into the closed drainage system. The front drop off area will sheet flow into a "rain garden" located at the front of the building. All areas within PR-1A will eventually enter into the subsurface stormwater infiltration/detention area to reduce the rates of runoff by collection and infiltration. The volume of runoff contained within the rain gardens were not factored into the mitigation for peak attenuation as a safety factor in the design. Rain Gardens: Rain Gardens are proposed at the front and rear of the Adult Center. The rain gardens will support a variety of indigenous plants that can survive in wet and dry conditions. The top of the rain garden is flush with the surrounding grade and will provide easy access for garden enthusiasts. The rain garden is placed in areas that are not"out of sight/out of mind" as they can be easily incorporated into the outdoor programming within close proximity to the pervious patio and front entry. These rain garden has been designed to collect and infiltrate storinlvater, however this drainage analysis has not factored that into the calculations in order to provide a higher safety factor when calculating the reduction in runoff volunnes and rates. Water Quality Inlets: Where water is not collected by the raingardens, catchbasins equipped with water quality units capable of providing 80% total suspended solids (TSS) removal will capture, clean and route the stormwater to the onsite detention /detention basin or the town's closed drainage system. Detention / Infiltration Basin: An underground stormwater infiltration and detention basin is located in the western portion of the lot. It is equipped with pipes and manholes to provide access and inspection. The stormwater enters into the site and travels through a series of perforated pipes surrounded by washed crushed stone that allows stormwater to enter into the ground.. This basin mitigates the runoff rate of stormwater leaving the site. Drainage Area PRA B Drainage Area PRA B encompasses the parking and perimeter areas not incorporated into the above area. The area continues to sheetflow toward the western perimeter towards and into the Surrey Drive closed drainage system. To provide drainage protection to the southern abutters, a gentle swale and low collection areas are provided to direct water into the on-site mitigation system and away from the neighbors as well as provide added infiltration. A series of Stormceptors are provided to collect the stormwater and clean it to DEP standards. DeVellis Zrein, Inc. May 24,2019 12 North �'ndover, MA Drainage Report Proposed Drainage Area Summary The following summarizes the proposed drainage areas, including the pertinent information used for the hydrologic analysis: Proposed Conditions Drainage Area Characteristics Summary: Drainage Area Area Curve Tr (min.) (Acres) Number PR-IA 0.50 94 6.0 PR-1 B 1.0 88 6.0 Peak Discharge Runoff Rates The proposed peak flow rates, tributary to the drainage point, were calculated for the 2, 10 and 100-year storm events in accordance with guidelines given in DEP's Stormwater Management Policy. Results are presented in the following table. Refer to Proposed Watershed Plan for a delineation of the watershed areas and their respective points of concentration. Summary of Results As previously stated, the resultant post-development peak discharge rates for the discharge points are less than the pre-development peak discharge rates. The following table provides a summary of the pre and post development data. The following table demonstrates peak flows at the design points for each of the design storms has been met. Peak Rates of Runoff Leaving the Site: Location 2-Year Storm 10-Year Storm 100-Year Storm Exist Prop Exist Prop Exist Prop (cfs) (cfs) (cfs) (cfs) (cfs) (cfs) DP-1 3.26 3.21 5.33 4.86 8.61 7.43 DeVellis Zrein, Inc. May 24,2019 13 ®� WATERSHED LIMIT PR-1A WATERSHED AREA DISCHARGE POINT�..� SUTTON STREET DP-1 J'J -♦f — — — — — I DP-1 . PR-1B .... i ... ♦ j w ® I Q ■ I �D ■ ® i U' PR-113 ® ® ■ 0' 25' 50' 100' Site Planning,Civil Engineering,Landscape Architecture Sketch No. Job#: Po Box 307 Foxborough,MA Drawn by: IAZ Checked By: S08.473.41 14 phone PR __ _ develliszrein.com Date: 05.20.19 eVellis Zrein Inc. Project North Andover Scale: 1°=50' Title: Proposed Watershed Map Adult Center i North��dult Center Andover, ' Drainage Report 4. Methodology and Design Criteria Hydrologic Model The drainage analysis was performed using the Soil Conservation Service (SCS) TR-20 method and the drainage software HydroCAD 7.10, as developed by Applied Microcomputer Systems. Data used in the design is as follows: Desiqn Storms Rainfall data for the 2, 10 and 100- year frequency rainfall events (for a 24-hour precipitation) was taken from the Rainfall Frequency Atlas of the Unites States (TP-40). The following table outlines the rainfall used for the TR-20 method. Rainfall Data Storm Event Rainfall 2-Year 3.40 inches 10-Year 4.80 inches 100-Year 7.0 inches Time of Concentration The `time of concentration' (T,) for each watershed was determined by finding the time necessary for runoff to travel from the hydraulically most distant point in the watershed to the point of concentration. The travel path was drawn based on the topography and the time was calculated using the TR-55 Method and HydroCAD. A minimum T,of 6.0 minutes was used. Curve Numbers Based on the cover type and hydrologic soil group, a weighted curve number(CN)was determined for each of the watersheds utilizing the SCS TR-55 method. DeVellis Zrein, Inc. May 24,2019 15 Adult Center • Andover,_ ' Drainage Report 5. Department of Environmental Protection Stormwater Management Standards Standard 1: No new stormwater conveyances (e.g. outfalls) may discharge untreated stormwater directly to or cause erosion in wetlands or waters of the Commonwealth. The project does not propose any new untreated outfalls or discharge of untreated water into wetlands or waters of the Commonwealth. All proposed impervious surfaces will be collected and treated with a catch basin, water quality units, rain gardens and treated and detained on-site with a detention / recharge system. Standard 2: Stormwater management systems shall be designed so that the post-development peak discharge rates do not exceed pre-development peak discharge rates. This Standard may be waived for discharges to land subject to coastal storm flowage as defined in 310 CMR 10.04. The project will reduce the post-development stormwater peak discharge rate to pre-development conditions via infiltration pipes and a detention / recharge system. Standard 3: Loss of annual recharge to groundwater shall be eliminated or minimized through the use of environmentally sensitive site design, low impact development techniques, stormwater best management practices, and good operation and maintenance. At a minimum, the annual recharge from the post- development site shall approximate the annual recharge from pre-development conditions based on soil type. This Standard is met when the stormwater management system is designed to infiltrate the required recharge volume as determined in accordance with the Massachusetts Stormwater Handbook. The intent of this standard is to ensure that the infiltration volume of precipitation into the ground under post-development conditions is at least as much as the infiltration volume under pre-development conditions. Standard 3 requires the restoration of recharge, using infiltration measures and careful site design. The project will provide groundwater recharge. The infiltration provided within the detention / recharge system recharges stormwater back into the ground per the required amounts. The NRCS classifies soils into one hydrologic groups, C, indicative of the minimum infiltration obtained for a soil after prolonged wetting. Group A soils have the lowest runoff potential and the highest infiltration rates, while Group D soils have the highest runoff potential and the lowest infiltration rates. The required recharge volume, the stormwater volume that must be infiltrated, was determined using existing site conditions and the infiltration rates set forth below. DeVellis Zrein, Inc. May 24,2019 16 North�Adult Center Andover, ' Drainage Report Hydrologic Group Volume to Recharge (Total Impervious Area) Hydrologic Volume to Recharge Total Group Impervious Area A 0.60 inches of runoff B 0.35 inches of runoff C 0.25 inches of runoff D 0.10 inches of runoff The soils are defined by the Soil Conservation Services (SCS) Soil Survey of Middlesex County, Massachusetts. The site is comprised of one soil type. Based on the published mapping and confirmed with the on-site soil testing, it was determined that the developable areas fall entirely within category C. Standard 4: Stormwater management systems shall be designed to remove 80% of the average annual post-construction load of Total Suspended Solids (TSS). This standard is met by this project: a) Suitable practices for source control and pollution prevention are identified in a long-term pollution prevention plan, and thereafter are implemented and maintained; b) Structural stormwater best management practices are sized to capture the required water quality volume as determined in accordance with the Massachusetts Stormwater Handbook; and c) Pretreatment is provided in accordance with the Massachusetts Stormwater Handbook. The stormwater runoff from the proposed parking spaces will exceed the 80% TSS removal as the project is equipped with catch basin s/water quality units, and a detention / recharge basin. A long term Operation and Maintenance Plan associated with this project has been designed and is included within this report. DeVellis Zrein, Inc. May 24,2019 17 lAdult Center • Andover, ' Drainage Report Standard 5: Regards land uses with higher potential pollutant loads: This is Not Applicable. Standard 6: Stormwater discharges within the Zone II or Interim Wellhead Protection Area of a public water supply and stormwater discharges near or to any other critical area require the use of the specific source control and pollution prevention measures and the specific structural stormwater best management practices determined by the Department to be suitable for managing discharges to such areas, as provided in the Massachusetts Stormwater Handbook. This is Not Applicable. Standard 7: Regards redevelopment projects: Although this property is currently developed, for the purpose of setting a high standard, the waivers and lower thresholds allowed for meeting redevelopment standards have been waived and this project meets or exceeds all applicable standards for new development. Standard 8: A plan to control construction-related impacts, including erosion, sedimentation, and other pollutant sources during construction and land disturbance activities (construction period erosion, sedimentation, and pollution prevention plan) shall be developed and implemented. The Grading and Drainage Plan contains provisions for the construction related items such as silt controls and Operation and Maintenance provisions for construction and post construction activities. This project schedule is to be coordinate with the abutting residential development and as such, items like shared earthwork, construction entrances, final limits of work etc, need more coordination efforts. The Site Drawings issued for Construction will contain more information and will be provided to the town throughout the process. A NPDES/SWPPP will be required and when a contractor is awarded the project, this plan will be submitted with all of the appropriate information on it. Standard 9: A Long -Term Operation and Maintenance (O&M) Plan shall be developed and implemented to ensure that stormwater management systems function as designed. The Long-Term Operation and Maintenance Plan has been prepared within this report and referenced on the plans that include the routine and non-routine maintenance tasks to be undertaken after construction is complete and a schedule for implementing those tasks. Standard 10: All illicit discharges to the stormwater management system are prohibited. DeVellis Zrein, Inc. May 24,2019 18 Adult Center, Andover, ' Drainage Report Standard 10 prohibits illicit discharges to stormwater management systems. By acceptance of this document, the Town of North Andover acknowledges that the stormwater management system is the system for conveying, treating, and infiltrating stormwater on-site, including stormwater best management practices and any pipes intended to transport stormwater to the groundwater, a surface water, or municipal separate storm sewer system. Illicit discharges to the stormwater management system are discharges that are not entirely comprised of stormwater. This document shall serve as the Illicit Discharge Compliance Statement verifying that no illicit discharges exist on the site and within the pollution prevention plan measures to prevent illicit discharges to the stormwater management system, including wastewater discharges and discharges of stormwater contaminated by contact with process wastes, raw materials, toxic pollutants, hazardous substances, oil, or grease. DeVellis Zrein Inc. May 24,2019 19 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report A. Introduction Important:When A Stormwater Report must be submitted with the Notice of Intent permit application to document filling out forms compliance with the Stormwater Management Standards. The following checklist is NOT a substitute for on the computer, (wh ich hi Report R t St e Stormwater e wc should provide more substantive and detailed information offered use only the tab the p p ) but is o key to move your here as a tool to help the applicant organize their Stormwater Management documentation for their cursor-do not Report and for the reviewer to assess this information in a consistent format. As noted in the Checklist, use the return the Stormwater Report must contain the engineering computations and supporting information set forth in key. Volume 3 of the Massachusetts Stormwater Handbook. The Stormwater Report must be prepared and Qcertified by a Registered Professional Engineer(RPE) licensed in the Commonwealth. The Stormwater Report must include: F • The Stormwater Checklist completed and stamped by a Registered Professional Engineer(see page 2) that certifies that the Stormwater Report contains all required submittals.' 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. 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. 04/01/08 Stormwater Report Checklist•Page 1 of 8 20 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 JAM Ea - VIM civil 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 04/01/08 Stormwater Report Checklist•Page 2 of 8 21 Massachusetts Department of Environmental Protection i 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): Rain Garden 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. 04/01/08 Stormwater Report Checklist•Page 3 of 8 22 Massachusetts Department of Environmental Protection Ll� 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 Field' ® 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. 21 E 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. 21 E site or a solid waste landfill and a mounding analysis is included. 80%TSS removal is required prior to discharge to infiltration BMP if Dynamic Field method is used. 04/01/08 Stormwater Report Checklist•Page 4 of 8 23 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. 04/01/08 Stormwater Report Checklist•Page 5 of 8 24 Massachusetts Department of Environmental Protection i - 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 '/"or V 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 notcover 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. 04/01/08 Stormwater Report Checklist•Page 6 of 8 25 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; a 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, 04/01/08 Stormwater Report Checklist- Page 7 of 8 26 Massachusetts Department of Environmental Protection i 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. 04/01/08 Stormwater Report Checklist-Page 8 of 8 27 Ad it C r U en el North • • - Drainage Report 6. Operation and Maintenance Plan Introduction DeVellis Zrein Inc. has prepared this report as a guide to establish maintenance protocol for the on-site drainage improvements serving the Proposed Adult Center. The goal of the Storm Water Operation and Maintenance Plan is not only to protect off-site wetlands and water resources abutting the site, but also to protect those resources in the region that may be affected by the activities at the site. The proposed site drainage improvements include: • Water Quality Inlets • Rain Gardens • Pervious Patio Pavers • Drain pipe network; • Detention and Infiltration System The proposed water quality treatment measures will result in improved removal of the total suspended solids (TSS) load in runoff from the site for the proposed parking improvements as well as throughout the existing parking areas. An effective drainage maintenance program will ensure that the removal of TSS from the stormwater runoff continues for the life of the facility. The Operation and Maintenance Plan will be implemented by the Owner of the property. Source Control The first tier of non-structural controls includes a comprehensive source control program of regular sweeping and maintenance of the stormwater management components. Pavement Sweeping Program While certain types of street sweepers are not effective for the removal of fine particulates and pollutants associated with them, most are quite effective for the removal of large quantities of sand, grit, and assorted inorganic and organic debris. Larger material carried in storm water poses an environmental threat not only by degrading aesthetics, but may also contribute pollutants as it degrades over time. In addition, larger materials may clog conveyance systems, reduce the efficiency and longevity of treatment systems and ultimately result in more maintenance downstream. The removal of contaminants directly from paved surfaces before contact with storm water is a valuable method for reducing pollutant loading in stormwater. It is proposed that the parking and drive areas will be cleaned with a street sweeper on a semiannual basis with at least two sweepings per year or more often as required if conditions require it. An alternative to a street sweeper is hand sweeping and hand held leaf blowers to collect and clean the parking lot as the area is relatively small. DeVellis Zrein, Inc. May 24, 2019 28 • ult__Center North Andover, Drainage Report Sweeping at the end of the winter season is to remove sand applied during the winter which typically migrates to the edges of paved areas and once in the fall to remove debris and organics accumulated in the summer and fall seasons. Water Quality Unit The new water quality units at the site will be equipped with specific catchment systems that will need to be cleaned per manufacturer's specifications. The water quality units will be cleaned during the same schedule as the catch basins. Rain Garden The rain garden should be cared for like any flower garden with several exceptions. The plant selection has been made by a landscape architect and represents a selection that is indigenous to New England, can survive in wet and dry conditions with little use of fertilizers or excessive watering. The bottom strip of stone shall be maintained free of organics and dirt to allow infiltration. The inlet pipes or curb openings shall be kept clear of obstruction. Side slopes shall be kept planted and side erosion shall be avoided. Pervious Patio Pavers While certain types of leaf blowers are not effective for the removal of fine particulates and pollutants associated with them, most are quite effective for the removal of sand, grit, and assorted inorganic and organic debris. Larger material carried in storm water poses an environmental threat not only by degrading aesthetics, but may also contribute pollutants as it degrades over time. In addition, larger materials may clog conveyance systems, reduce the efficiency and longevity of treatment systems and ultimately result in more maintenance downstream. The removal of contaminants directly from paver surfaces before contact with storm water is a valuable method for reducing pollutant loading in stormwater. It is proposed that the pervious patio paver patio be cleaned with a leaf blower on a semi-annual basis (spring and fall), with at least two blowings per year. Detention and Infiltration System The actual removal of sediments and associated pollutants and trash occurs only when inlets are cleaned out; therefore, regular maintenance is required. The stormwater that enters into the infiltration system will be devoid of sediment due to the TSS removal within the components leading up to the system. In order for sediment to reach the system, it would have to pass through the raingardens, catch basins and water quality inlets before reaching the infiltration system. All of the treatment components referenced provide a higher level of sediment removal than required and it is very unlikely that sediment will accumulate in the system. If sediment is observed in the system it can be easily removed with a vacuum truck similar to a septic system pumper. DeVellis Zrein,Inc. May 24,2019 29 Adult - - ' • • - ' Drainage Report The underground detention and infiltration basin has been designed with oversized manholes and pipes for easy access and viewing. There are 4-foot diameter manholes at each corner of the system (4 total) and 12-inch header pipes along the sides connecting to 12-inch diameter perforated infiltration pipes, accessed from each manholes that are provided for easy viewing and maintenance. During Construction • Prior to construction, install tree protection and erosion and sediment control measures as shown on the plan and details. • The site contractor shall inspect all sediment and erosion control structures after each rainfall event and at the end of the working day. • All measures shall be maintained in good working order. If repair is necessary, it shall be initiated within 24 hours of inspection. • Silt shall be removed from the silt fence if 3-inches or greater and as needed. • Sediment shall be contained within the construction site and away from drainage structures. • Damaged or deteriorated erosion control measures will be repaired immediately after identification • The silt fence shall be kept in close contact with the ground and reset as necessary. • The contractor's site superintendent will be responsible for inspection, maintenance and repair activities. • All disturbed areas will be treated with 4" of topsoil and seed. • Remove siltation controls upon completion of permanent vegetation over disturbed areas. • A preconstruction meeting shall take place prior to construction and the contractor shall present a plan for vehicle entrance/exiting and vehicle washout areas. At the time of this report, there is no contractor involved in the project. It is the opinion of DeVellis Zrein, Inc. that it is in the best interest of the Town of North Andover not to dictate the means and methods of the specific site setup for the contractor, but rather require the contractor to provide this information prior to construction. Stormwater Management System Owner This site is owned by the Town of North Andover and the town will continue to perform site maintenance and operations. Estimated Operations Budget It is not anticipated that the stormwater maintenance required would be considered extraordinary: A yearly estimated operations budget for consideration to carry out the Operations and Maintenance Plan requirements is as follows: DeVellis Zrein, Inc. May 24,2019 30 Adult Cent- prth Andover, ' Drainage Report • $0: Inspect the perimeter landscaping annually, in the spring, for erosion of side slopes, embankments, and accumulated sediment. Necessary sediment removal, earth repair and/or reseeding shall be performed immediately upon identification. • $1000: Clean all water quality structures annually to remove accumulated sand, sediment, and floatable products. Dispose and transport accumulated sediment off-site in accordance with applicable local, state and federal guidelines and regulations. This should be incorporated into the DPW routine maintenance protocol. • $400: Remove accumulated leaves and debris from catch basins and outlet openings. • $500: Routinely pick up and remove litter from the parking areas, islands and perimeter landscape area, in addition to pavement sweeping. • $500: Replant/replenish the rain gardens with specific plantings. Trim and prune as needed. DeVellis Zrein,Inc. May 24,2019 31 I � 14 ! - Y 1 " , ,, i s rJ c y 1 1 s 11,E ,t �v 1 When it rains, oils, sediment and other contaminants are captured and contained by over 20,000 Stormceptor units operating worldwide. While Stormceptor's patented scour prevention technology ensures captured pollutants remain in the unit during all rainfall events, the accumulated pollutants must eventually be , removed as part of a regular maintenance program. If neglected, oil and sediment gradually build up and diminish any BMP's efficiency, harming the environment and leaving owners and operators vulnerable to fines, surcharges and bad publicity. Ease, frequency and cost of maintenance are often overlooked by specifiers when considering the merits of a stormwater treatment system. In reality, maintenance is fundamental to the long-term y performance of any stormwater quality treatment device. w While regular maintenance is crucial, it shouldn't _ be complicated. An ongoing maintenance w program with Stormceptor is convenient and practically effortless. With virtually no disruptions, you can concentrate on your core business. tires Inspections are easily carried out above ground from any standard surface access cover through a visual inspection of the orifice and drop tee components. A sludge judge and oil dip-stick are all that are needed for sediment and oil depth measurements. E Maintenance is typically conducted from the same surface access cover, eliminating the need for confined space entry into the unit. Your site remains undisturbed, saving you time and money. J.E. 32 No MUSS, no fuss and 'past Maintenance is performed quickly and inexpensively with a � r standard vacuum truck. Servicing usually takes less than )� two hours, with no disruption to your site. r A complete stormwater management plan for Stormceptor `, extends beyond installation and performance to regularIII L am _ maintenance. It's the smart, cost-effective way to ensure r your unit continues to remove more pollutants than any other separator for decades to come. 'l ( "`ff. `i alnienan (� recor��r ��d tion • Units should be inspected post-construction, prior to being put into service. • Inspect every six months for the first year of operation to determine the oil and sediment accumulation rate. • In subsequent years, inspections can be based on first-year observations or local requirements. • Cleaning is required once the sediment depth reaches 15% of storage capacity, (generally taking one year or longer). Local regulations for maintenance frequency may vary. • Inspect the unit immediately after an oil, fuel or chemical spill. • A licensed waste management company should remove captured petroleum waste products from any oil, chemical or fuel spills and dispose responsibly. With over 20,000 units operating worldwide, Stormceptor performs and protects every day, in every storm. Of i . www.ii);briunisystem y.coil) USA:(888)279 8826 Cr?t ADA:(800)595 4801. 33 Center Andover, ` Drainage Report Appendix A — Hydrologic Calculations and Drain Pipe Calculations • Hydrologic Model - Existing Conditions Stormwater Runoff Area Calculations Existing Conditions Calculations 2-Year Storm 10-Year Storm 100-Year Storm • Hydrologic Model - Proposed Conditions Stormwater Runoff Area Calculations Proposed Conditions Calculations 2-Year Storm 10-Year Storm 100-Year Storm DeVellis Zrein, Inc. May 24,2019 34 Adult Center • Andover, ' Drainage Report Hydrologic Model - Existing Conditions DeVellis Zrein, Inc. May 24,2019 35 EX ,= 1 t in Subcat Reach Pon Link Routing Diagram for Existing Conditions ❑ Prepared by DeVellis Zrein Inc., Printed 5/20/2019 HydroCAD®10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC 36 North Andover Adult Center Existing Conditions Prepared by DeVellis Zrein Inc. Printed 5/20/2019 HydroCADOO 10 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 0.981 79 50-75%Grass cover, Fair, HSG C (EX-1) 0.489 98 Buildings, Paved Areas HSG C (EX-1) 1.471 85 TOTAL AREA 37 North Andover Adult Center Existing Conditions Type ///24-hr 2-year Rainfall=3.40" Prepared by DeVellis Zrein Inc. Printed 5/20/2019 HydroCADO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Paoe 3 Summary for Subcatchment EX-1: Site Runoff = 3.26 cfs @ 12.09 hrs, Volume= 0.236 af, Depth= 1.93" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type III 24-hr 2-year Rainfall=3.40" Area (sf) CN Description 21,317 98 Buildings, Paved Areas HSG C 42,748 79 50-75% Grass cover, Fair, HSG C 64,065 85 Weighted Average 42,748 66.73% Pervious Area 21,317 33.27% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: Site Hydrograph 1 3.26 cfs ®Runoff I I I I I I I 1 I I I I I I I I I I I I I I I 1 I I I 1 I I I I I I I I I I I I I I I I I I 3 _ .. I TOI e-I1I 2I 4-I hrI _. I I I I I 2-yearl R; 4MM11-- .40" I I I I I I I I I I I I I I I I I I I I I I I I I I I �3'I I I Runoff Are'a=64,065�sf I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I yN. 2_ _.L_ ..._L_..1 _.I_._.!.._._I_.-... 4.... _I_....L__. _ Ru_roffVolu_me®;0.236;_af_ I � I I I I I I I - I 1 I I I I I I I I I I I I Runoff Depth 1�.9;3' I I I 1. I 1 I�c-61®�Imin i - 1 1 1 C N-85 1 L. ._I_ _I__.1.I _. I I I I I I I I I I I I I I I I I I I i I I I I I 1 I I 1 I I I I I I I I I I I I I I I I 1 I I I I I 1 I I I I I I 1 I 1 I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I t I 1 I I I I I I I I I 1 I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I 0 ...I.�i�l. ..1... 1... .i..,.�. it ...1. 1. 1.. �1... , . 1 ... .�,... ... 1 ...1....1. ..1.. .1. ..1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) 38 North Andover Adult Center Existing Conditions Type 111 24-hr 10-year Rainfall=4.80" Prepared by DeVellis Zrein Inc. Printed 5/20/2019 HydroCAD010.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment EX-1: Site Runoff = 5.33 cfs @ 12.09 hrs, Volume= 0.390 af, Depth= 3.18" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type III 24-hr 10-year Rainfall=4.80'r Area (sf) CN Description 21,317 98 Buildings, Paved Areas HSG C 42,748 79 50-75% Grass cover, Fair, HSG C 64,065 85 Weighted Average 42,748 66.73% Pervious Area 21,317 33.27% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: Site Hydrograph 5.33 cis �•Runoff I I I I I I I I I I i I I I I I I I I I I I I I I I I I I I I I I I I I I i 1 I I I I I I I I i I I I I I I I 5 _;Ty 'e 111 24-ihr- I 1 Y I I 10-yeah Rainfall 4,.8'0';` - 4 � RuI nI ofI f Area'64;065rsf I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I !Runoff;V61661e-0.396 of I I I I I I I I I I I I I I I I I I I I I I I I I i I I 3 3 - -, - - - - ,--,-- -;-Ru n-off-Depth--'3.1,8,,_ . 1 1 1 1 LL 1 I 1 I I I I I I I I I I I I I I I I I I I I I I I I, 1 I 1 r- r- -r -r -_,--r- r r I r I I I 1 18 5- I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I _ 1 I i I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I 1 I I I I I I i I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I 1 I I o D 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) 39 North Andover Adult Center Existing Conditions Type 11124-hr 100-year Rainfall=7.00" Prepared by DeVellis Zrein Inc. Printed 5/20/2019 HydroCADO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment EX-1: Site Runoff = 8.61 cfs @ 12.09 hrs, Volume= 0.644 af, Depth= 5.25" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Type III 24-hr 100-year Rainfall=7.00" Area(sf) CN Description 21,317 98 Buildings, Paved Areas HSG C 42,748 79 50-75% Grass cover, Fair, HSG C 64,065 85 Weighted Average 42,748 66.73% Pervious Area 21,317 33.27% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: Site Hydrograph - I I I I � I I � I I 1 , ®Runoff ___ _I___ 1 � 6- . ., .. ..,--,—,--1— 1 7 --I--7I -,--I- _ ,- ,. _,.. _,__� _, ,...._,. . ., ,TY e,11' 21 ,hr_ _ 4 I I I I I I I I I I I I I I I I I I I I I I, .0 7- - 00-yea+_Ra•nfall.. 0"I Runoff Area=64,065 sf 6-.. "- -.... _I'-,.. - 4' `i.._. .....{._...,.__.{._._.;......,_._.t.._...I_-I...._.{_._I-...,.....-1--I-- 1 "" - -I--{...._ RUnoff;Volume-;0.64t of 51 _I_._i_....I_._J_..1_ Runoff Depth=I5,.25" U. 4- . .._I... ..I.. - -, _ 0 rc= I I _ I I I 1 1 3- - i- r _'I._-r _.. .. _.L___..._ .....r r -1 r_ CN®85..._. 2- __I' -f -f--1-'-t-- I 1 1 1 I I I I 1 I I I I I I I I I I I 1 I I I I I I I I i 0-.. . 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) 40 �Adult Center NorthAndover, ' Drainage Report Hydrologic Model - Proposed Conditions DeVellis Zrein, Inc. May 24,2019 41 E A PR1 B Detained n-Detained 1P Detention B in DP-1 DP-1 Subcat Reach Pon Link Routing Diagram for Proposed Conditions-PIPE Prepared by DeVellis Zrein Inc., Printed 5/23/2019 HydroCAD®10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC 42 North Andover Adult Center Proposed Conditions-PIPE Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADO 10 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Paqe 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 0.499 74 >75% Grass cover, Good, HSG C (PR1 A, PR1 B) 0.191 98 Building, HSG C (PR1 A) 0.192 98 Parking, Walkways, HSG C (PR1 A) 0.588 98 Paved parking, HSG C (PR1 B) 1.471 90 TOTAL AREA 43 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 2-year Rainfall=3.40" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 3 Summary for Subcatchment PR1 A: Detained Runoff = 1.38 cfs 9 12.09 hrs, Volume= 0.105 af, Depth= 2.74" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type III 24-hr 2-year Rainfall=3.40" Area (sf) CN Description 8,304 98 Building, HSG C 3,360 74 >75% Grass cover, Good, HSG C 8,376 98 Parking, Walkways, HSG C 20,040 94 Weighted Average 3,360 16.77% Pervious Area 16,680 83.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR1 A: Detained Hydrograph I I I I I I I I I I I I I I I I I 1 1 I I I I I I I I I I I I I I I I 1 1 1.36 cfs 1 ®Runoff 1 1 I I I I I I I I I I I I I I 1 I I I I I I I ! 1 I I 1 I I I I I 1 I I yp Te ,11124-hr I I I I I I I I � ;' ; 2-yea� Rai;n�a113.40" I I I I I I I I I I I I I I 1 I I I I I I I I I I I 1 I I I I I I I I I 1 I I I I I I I- 1 1 4 ; _ Run'offAr6a-20iI040 8f I I I I I I I I I I I I I I I 1 1 I I I I I I I I I I 1 I I I I N Ru'noft;V;o1dm6=,'0 A p5 of RunoffDepth-2.74" 1 I I I I ' I T6®I0.0 tinin 1 CN=94 1 i I I I I I I 1 I I I I 1 I I I I I I 1 I I I I I I I I I I I I I o_ I I I . 0 1 2 3 4 5 6 7 8 9 1011 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 44 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 2-year Rainfall=3.40" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCAD010 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment PR1 B: Un-Detained Runoff = 2.51 cfs @ 12.09 hrs, Volume= 0.183 af, Depth= 2.18" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type III 24-hr 2-year Rainfall=3.40" Area (sf) CN Description 25,635 98 Paved parking, HSG C 18,390 74 >75% Grass cover, Good, HSG C 44,025 88 Weighted Average 18,390 41.77% Pervious Area 25,635 58.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR1 B: Un-Detained Hydrograph I 2.51 cis 1 I I ®Runoff I I I I I I 1 1 I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I 1 1 r 1 I I I I I I I I I r 1 1 I ( 1 r r Type'lll 24-hr I I I I I I I I I I I I 1 r I I I I I I I 1 1 I I I I I I I I I I r I I I I 1 1 I I r I I I I I 1 I I 1 I I I I I I I - I I I I 1 I I I � I I I I I I I I I I I � I I r I •I � I I � I 1 1 1 2-yea Ral;nfall;3.4U" 2- -,-_ Runoff!Area-44jI025 sf I I � I I I I I t 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Runoff IV,,ojOme-0 A 8, 8 of i I I I I I � I v 1 I I I I I I I I I I I I I Runoff Depth,2.18" LL I I I I I I I I I I I I I I I t 1 I I I I I I I I I wI I I I I - I I I I I I I I I I I I I I I I I I I I I I I I I I TV-61 0 min, I I I I I I I I I I I I I I I I I I• C N-8 8 I AI I I I I I I I I I I I I I I I I I 1 I III I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I 1 I 1 I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I 1 I I I I I r 1 I I I I I I I I I I I I I I I I I 1 I I I I 1 I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I r I I I I I I I I I I I t I I I I I I I I I I I I I I 1 I I I I I I 1 I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I 1 I I I I I r I I I I 1 I I I I I I 1 I I I I I r r 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 45 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 2-year Rainfall=3.40" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADOO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 5 Summary for Reach DP-1: DP-1 Inflow Area= 1.471 ac, 66.05% Impervious, Inflow Depth = 2.15" for 2-year event Inflow = 3.21 cfs @ 12.10 hrs, Volume= 0.264 of Outflow = 3.21 cfs @ 12.10 hrs, Volume= 0.264 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Reach DP-1: DP-1 Hydrograph 1 i 1 1 I —Inflow III 1 3.21 of$ 1 I Outflow 1 I I I I I I I I 1 I I I I I I I I I I I I I 1 I I I I I1 I I I I I 1IIIIIIII ■IIIIIIII 41IIIII17 II1II1III1 IiII1 KIIIIiIII V1IIIIIIII13- Infow Area® - - - 1 -I- T- 1. -1-rI _r-r -ri - _ I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I b I I I I I i I I I I I I 1 I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I 1 I I I ( I I I I I I I I I I 1 I I 1 1 I I I I 1 I I I I I I I I 1 I I I I I I I I I I 1 I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I 1 1 I 1 I I I I 1 I I I I I I I I I I I I I i I I I I I I I 1 1 I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 ! I I I I I I I I I I I I I I I I I I I i I I I I I I I I I 1 I i 1 I I I 1 I I 1 I I I I I I I I I i I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I 0 1 2 3 4 5 6 7 8 9 1011 12 1314 1516 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 46 North Andover Adult Center Proposed Conditions-PIPE Type ///24-hr 2-year Rainfall=3.40" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCAD®10 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 6 Summary for Pond 1 P: Detention Basin Inflow Area= 0.460 ac, 83.23% Impervious, Inflow Depth = 2.74" for 2-year event Inflow = 1.38 cfs @ 12.09 hrs, Volume= 0.105 of Outflow = 0.81 cfs @ 12.21 hrs, Volume= 0.105 af, Atten= 41%, Lag= 7.2 min Discarded = 0.01 cfs @ 12.21 hrs, Volume= 0.024 of Primary = 0.80 cfs @ 12.21 hrs, Volume= 0.081 of Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Peak Elev= 162.94' @ 12.21 hrs Surf.Area= 1,960 sf Storage= 938 cf Plug-Flow detention time= 64.6 min calculated for 0.105 of (100% of inflow) Center-of-Mass det. time= 64.9 min ( 850.0 - 785.1 ) Volume Invert Avail.Storage Storage Description #1 162.00' 1,260 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,920 cf Overall - 770 cf Embedded = 3,150 cf x 40.0%Voids #2 162.50' 770 cf 12.0" Round Pipe Storage x 14 Inside#1 L= 70.0' 2,030 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 162.00 1,960 0 0 163.00 1,960 1,960 1,960 164.00 1,960 1,960 3,920 Device Routing Invert Outlet Devices #1 Discarded 162.00' 0.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 156.00' #2 Primary 162.25' 8.0" Round Culvert L= 106.0' CMP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 162.25'/ 158.00' S= 0.0401 '/' Cc= 0.900 n= 0.011 Concrete pipe, straight & clean, Flow Area= 0.35 sf Discarded OutFlow Max=0.01 cfs @ 12.21 hrs HW=162.94' (Free Discharge) Li=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=0.80 cfs @ 12.21 hrs HW=162.94' (Free Discharge) t--2=Culvert (Inlet Controls 0.80 cfs @ 2.28 fps) 47 North Andover Adult Center Proposed Conditions-PIPE Type Ill 24-hr 2-year Rainfall=3.40" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADOO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 7 Pond 1 P: Detention Basin Hydrograph 1 1.38 CfS 1 I 1 1 1 1 I Inflow I I 1 m Outflow 1 1 1 1 1 1 I I 1 Discarded Inflow Area=0.460 'a'c' ®Primary I I I 1 1 Pe'W EleV=162.94'! I I � I I I I I _ storage 938;-cf _ . OI 1 1 1 I 1 1 u.. I I I i I I I I i I I I I I I I I I I I I I I I 1 I I I I I I I I I I 1 I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I i I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I 1 1 I I I I I I I I I I 1 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I ! I II I I I I i I I I I I I I I I I I I I I I I I 1 I 1 I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I i I I I I I I I I 1 1 I I I I I I i I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I 1 I I I I I I I I 1 I I I I 1 I 1 I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I i I 1 I I I I 1 I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I •01 Cf$ _. 0- . ..1.,,.1,. I,...1,..,1.,.I, ,.1 .,,1,... ,.,1,. .1,., ,...L.., ... ,..,I... .........,1.... .......1..,.1.,.1..,. ....1,,. 1 .,1.. . ...1....1....1.. ,I 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 2425 26 27 2829 3031 3233 3435 36 Time (hours) 48 North Andover Adult Center Proposed Conditions-PIPE Type 111 24-hr 10-year Rainfall=4.80" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADO 10 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment PR1 A: Detained Runoff = 2.02 cfs @ 12.09 hrs, Volume= 0.158 af,. Depth= 4.11" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type III 24-hr 10-year Rainfall=4.8011 Area (sf) CN Description 8,304 98 Building, HSG C 3,360 74 >75% Grass cover, Good, HSG C 8,376 98 Parking, Walkways, HSG C 20,040 94 Weighted Average 3,360 16.77% Pervious Area 16,680 83.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fUsec) (cfs) 6.0 Direct Entry, Subcatchment PR1 A: Detained Hydrograph I i 2.02 cis 1 1 —Runoff I I I 1 I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I 2 I I I I 1 1 - -I �� T I I I 011 24-hr I I I 1 I I I I I I I I I I I I I I I I I I I I I I 1 I I I I 10;-yeah Rain f all�-4.80" I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I 1 I I I I Run'offAre9-20;040 sf I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I N Runoff;V;o1urn6=',OA$8 of I I I I I 3 Runoff Depth-14.11 -f---I -_.-1 _- I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 11 I C N-9 4 I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I i I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I i I I I I I 1 I I I I I I 1 I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I i I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I i I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I i I I I I I I i I I I I I 1 I I I I I I I I I I I I I I I I I I I I i I I I I I I 1 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I 1 I I I I I I I I I I I I I ( I I I I O I ' �� .. .. 0 1 2 3 4 5 6 7 8 9 1011 12131415161718192021 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 49 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 10-year Rainfall=4.80" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment PR1 B: Un-Detained Runoff = 3.95 cfs @ 12.09 hrs, Volume= 0.293 af, Depth= 3.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type III 24-hr 10-year Rainfall=4.80" Area (sf) CN Description 25,635 98 Paved parking, HSG C 18,390 74 >75% Grass cover, Good, HSG C 44,025 88 Weighted Average 18,390 41.77% Pervious Area 25,635 58.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR1 B: Un-Detained Hydrograph ! 1 1 I I I I I I I I I I 3.95 C1$ I I I I I I I I I I 1 I I I I I I I I I I � s RUnOff I I I I I I i I I I I I I I I I I I I I I 1 I I I 1 I 1 10-year Rainfall;4.80" 3- ;I RunoffAre a-44�025._sfl._.. I I I I I I I I I I Ftu!noff;V,010n e-;0;203 of N I � i I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Runoff Depth®I3.48" ! I I I I I I I I I I i C N®8 8 I I I I I I I I 1 I I I I I I I I I I I II! III1IIII I IIIII II IIII I flit ,I I I I I I I I I I I II1 '17 _-1IIIIIII _.I 0 1 2 3 4 5 6 7 8 9 1 IIIIIII 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35776 Time (hours) 50 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 10-year Rainfall=4.80" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCAD010 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 10 Summary for Reach DP-1: DP-1 Inflow Area= 1.471 ac, 66.05% Impervious, Inflow Depth = 3.46" for 10-year event Inflow = 4.86 cfs @ 12.09 hrs, Volume= 0.424 of Outflow = 4.86 cfs @ 12.09 hrs, Volume= 0.424 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Reach DP-1: DP-1 Hydrograph I I 1 I 1 I I I I i I I I I I I I I I I I I I 1 I I I I I I I I I I I Inflow ow 5- -1_. 4.86 cfs Outflow I I 1 1 1 ' I I I I I I I I 1 I I I I I 1 1 I I I I I I I 1 I ! I I I I I I I I 1 Inflow Alfe'a®1 .47`1 46 I I I I I I I I I I I I I I I I I I I I I f I I I I I I I I I 1 I I I I I I I -......._.__..... ------- - -- 1 --------- — -------- . I 1 I I I I I I I I I I I 1 I I I I I I I 1 I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I i I I I I 1 I I I I I I I I 1 II ri3 -a--I_ 1--'-'-E--�--' -+_..i_.4_..i.._;.- `--'--"k- v I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I i I I 1 I I I 1 I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I i I I I I 1 I I I I I 1 I t I I I I I I I I I I I I I I I I I I 1 I I I I I 1 1 I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I 1 I I I I I I 1 I I I I I I I I I I I I I I I I i I I I I I I I I I I I I 1 i i I I I I I I I I I I I I I I I 1 I I I I I I I I 1 I I I I I I I I I I I I I I 1 I I 1 I 1 I I I I I I I I 1 I I I I 1 I I I I I I .1. .i - i....;-r-r... I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I 1 I I I I I I I I 1 I I I I I I 1 I I I i I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I i I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I �..�. ...I ,....�....I....,...r....�...I....r... ,..�.��..... ... .......... .�....r 1. .�..., �...1 .... 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 51 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 10-year Rainfall=4.80" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 11 Summary for Pond 1 P: Detention Basin Inflow Area= 0.460 ac, 83.23% Impervious, Inflow Depth = 4.11" for 10-year event Inflow = 2.02 cfs @ 12.09 hrs, Volume= 0.158 of Outflow = 1.08 cfs @ 12.22 hrs, Volume= 0.158 af, Atten=46%, Lag= 8.1 min Discarded = 0.01 cfs @ 12.22 hrs, Volume= 0.026 of Primary = 1.07 cfs @ 12.22 hrs, Volume= 0.131 of Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Peak Elev= 163.23' @ 12.22 hrs Surf.Area= 1,960 sf Storage= 1,330 cf Plug-Flow detention time= 52.9 min calculated for 0.158 of (100%of inflow) Center-of-Mass det. time= 52.7 min ( 827.3- 774.6 ) Volume Invert Avail.Storage Storage Description #1 162.00' 1,260 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,920 cf Overall - 770 cf Embedded = 3,150 cf x 40.0% Voids #2 162.50' 770 cf 12.0" Round Pipe Storage x 14 Inside#1 L= 70.0' 2,030 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 162.00 1,960 0 0 163.00 1,960 1,960 1,960 164.00 1,960 1,960 3,920 Device Routing Invert Outlet Devices #1 Discarded 162,00' 0.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 156.00' #2 Primary 162.25' 8.0" Round Culvert L= 106.0' CMP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 162.25'/ 158.00' S= 0.0401 '/' Cc= 0.900 n= 0.011 Concrete pipe, straight & clean, Flow Area= 0.35 sf Discarded OutFlow Max=0.01 cfs @ 12.22 hrs HW=163.23' (Free Discharge) t-1=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=1.07 cfs @ 12.22 hrs HW=163.23' (Free Discharge) L2=Culvert (Inlet Controls 1.07 cfs @ 3.05 fps) 52 North Andover Adult Center Proposed Conditions-PIPE Type III 24-hr 10-year Rainfall=4.80" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADO 10 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 12 Pond 1 P: Detention Basin Hydrograph 2.0 CfS e Inflow Outflow - Discarded InflOW '/"area-0.460 �altr' Primary //�� Pe'akEIeV�' 161?3, '� Storage ;l AQ; cf! 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 53 North Andover Adult Center Proposed Conditions-PIPE Type Ill 24-hr 100-year Rainfall=7.00" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADO 10.00-24 s/n 08761 ©2018 HydroGAD Software Solutions LLC Page 13 Summary for Subcatchment PR1 A: Detained Runoff = 3.02 cfs @ 12.09 hrs, Volume= 0.241 af, Depth= 6.29" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type III 24-hr 100-year Rainfall=7.00" Area (sf) CN Description 8,304 98 Building, HSG C 3,360 74 >75% Grass cover, Good, HSG C 8,376 98 Parking, Walkways, HSG C 20,040 94 Weighted Average 3,360 16.77% Pervious Area 16,680 83.23% Impervious Area Tic Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR1 A: Detained Hydrograph 3.02 cfs m Runoff I I I I I 1 I 1 I I I I I I I I I I I I I I I I I I I I I I I I 3- ...L.....L.._1-_.'._ '--1- '1 "' ._1- --'' --1 - _..1.._ _ _.L I I I I I I I I I I I I I Type 111 24-h r ' I I 1�0-year R�ai�n�all�-7.00" r I I Run'offArea®20j040 sf 1 1 I fill 2- Run_. _off I,Vo_ I_._I,__.1_._1 Ilu�rne_0 24� a 1 1 I RUh6ff Depth;6.29" I I I I . N 9-4 j ! 1 ! I_ L I _. i I 1._.1_.1._1 ... _L.-.l__.L _1__I_._I_ .. I_-.L... a I I 1 I I I I I I I I I I I I I I �...L._L �._I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I 1 I I I I I i L' L 1 I I 1 I I 0- I I I I . I ,. . I.. 1... I.. .I.. .I....I 1.. . .I. �. �... .... 1.. .1 � , , 0 1 2 3 4 5 6 7 8 9 1011 12131415161718192021 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 54 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 100-year Rainfall=7.00" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADOO 10 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 14 Summary for Subcatchment PR1 B: Un-Detained Runoff = 6.19 cfs @ 12.09 hrs, Volume= 0.471 af, Depth= 5.59" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type III 24-hr 100-year Rainfall=7.00" Area (sf) CN Description 25,635 98 Paved parking, HSG C 18,390 74 >75% Grass cover, Good, HSG C 44,025 88 Weighted Average 18,390 41.77% Pervious Area 25,635 58.23% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (fUsec) (cfs) 6.0 Direct Entry, Subcatchment PR1 B: Un-Detained Hydrograph 6.19 cfs I I I -flUnoff I I I I I I I I I I I I I I I I I I I I I I 6II II II II II I II II II LI ILI IIII tII IL T..II y_ p_.eII__II 1I.■II .2_II_4 J_-h!I rII .- I I I I I I 100-yea'r Rainfall;_7.00 1 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I i I ( Run'off Area_44;025 sf I I I I 4___,_ _, ;__,_ _;_, -;Ru;no f Vlo m -1 -471-M-- v I I I I I I I I I I I i I I I I I I I I I I I I I I 1 I I I 1 I I 1 R'unoff Depth _5.59" 30 I I 1 I I I I _ � I I ._ .. .. --I-..-t-�-'r._.�._.r._�.._r_.r-r-r-r-r- 61-0 3-' r _r...r-I-'-r- -I--r -r- r- '1-'I lV� Tc® On _ I i• I I I I I I I I 1 I I i I I I I I I I I I I I I I i I I I I 1 I I I I 1 I I 2---�-'-r� -r-I--1- I I I I� I I I 1 1-� I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I . I I 1 I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I 1 I I 1 I I I I I I I I I I f I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I O I i 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Time (hours) 55 North Andover Adult Center Proposed Conditions-PIPE Type 11124-hr 100-year Rainfall=7.00" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCADOO 10.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Paae 15 Summary for Reach DP-1: DP-1 Inflow Area = 1.471 ac, 66.05% Impervious, Inflow Depth = 5.58" for 100-year event Inflow = 7.43 cfs @ 12.09 hrs, Volume= 0.684 of Outflow = 7.43 cfs @ 12.09 hrs, Volume= 0.684 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Reach DP-1: DP-1 Hydrograph j J...j_ 1_-I .L.-L_.L. L. 1 1 1 1 1 1 —Inflow 7.43 cfs 1 Outflow I I I I I I I I I I I i I I I I 1 I I I I I I I I I I I I I I I 7_ I ff1#1-owl-A.'Va.�'... 4'■ ..Ial._. I I I I I I I I I I I I I I I I 1 I I I 1 I I I i I I I I '.CI ._F.._t-....I..._.I...._I..._I._...I.. r .a....� .4 I_- l.. _.-. _I.._I._-1._.I_...4...._I_..1--1- 4...J_.,__.4.._I-._I...._ I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I 1 I I I I i I I I I I I 1 I I 1 I I I I I 1 I I I I I I I I I I I I I I 1 I I I I I 1 1 1 1 1 1 1 0 4 r-r-r -r- I I I I 1 1 1 1 3- l-r r I I i I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I 1 I 1 I I I I I I I I I I I I I I 1 I I I I I I I I I I I I 1 I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I ---i___j1 L [ � _ 0 I I I I 1 I I 0 1 2 3 4 5 6 7 8 9 1011 12 13 14 15 16 17 18 19 20 21 222324252627282930313233343536 Time (hours) 56 North Andover Adult Center Proposed Conditions-PIPE Type ///24-hr. 100-year Rainfall=7.00" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCAD010 00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 16 Summary for Pond 1 P: Detention Basin Inflow Area= 0.460 ac, 83.23% Impervious, Inflow Depth = 6.29" for 100-year event Inflow = 3.02 cfs @ 12.09 hrs, Volume= 0.241 of Outflow = 1.55 cfs @ 12.23 hrs, Volume= 0.241 af, Atten= 48%, Lag= 8.6 min Discarded = 0.02 cfs @ 12.23 hrs, Volume= 0.028 of Primary = 1.54 cfs @ 12.23 hrs, Volume= 0.213 of Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Peak Elev= 163.92' @ 12.23 hrs Surf.Area= 1,960 sf Storage= 1,971 of Plug-Flow detention time=43.6 min calculated for 0.241 of (100%of inflow) Center-of-Mass det. time=43.3 min ( 807.9 - 764.6 ) Volume Invert Avail.Storage Storage Description #1 162.00' 1,260 of Custom Stage Data(Prismatic) Listed below (Recalc) 3,920 of Overall - 770 of Embedded = 3,150 of x 40.0%Voids #2 162.50' 770 of 12.0" Round Pipe Storage x 14 Inside#1 L= 70.0' 2,030 of Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 162.00 1,960 0 0 163.00 1,960 1,960 1,960 164.00 1,960 1,960 3,920 Device Routing Invert Outlet Devices #1 Discarded 162.00' 0.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 156.00' #2 Primary 162.25' 8.0" Round Culvert L= 106.0' CMP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 162.25'/ 158.00' S= 0.0401 '/' Cc= 0.900 n= 0.011 Concrete pipe, straight & clean, Flow Area= 0.35 sf Discarded OutFlow Max=0.02 cfs @ 12.23 hrs HW=163.92' (Free Discharge) L1=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=1.53 cfs @ 12.23 hrs HW=163.92' (Free Discharge) L2=Culvert (Inlet Controls 1.53 cfs @ 4.39 fps) 57 North Andover Adult Center Proposed Conditions-PIPE Type III 24-hr 100-year Rainfall=7.00" Prepared by DeVellis Zrein Inc. Printed 5/23/2019 HydroCAD010.00-24 s/n 08761 ©2018 HydroCAD Software Solutions LLC Page 17 Pond 1 P: Detention Basin Hydrograph 3.02 cis 1 Inflow I I I I I I I I I I I I I I 1 I I I I I 1 1 I u 3 `1- 1--1... --1- i ' J -L-I ---I" _L. -1 --1-'I- '-_1- - -L L ' I--1" -1- '1--1 1.. -Outflow 1 I I 1 I —Discarded Inflow Area-0.W lat ®Primary I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I 1 I I I I I 1 I I 1 I I I I I I I I I 1 I I I I I I I PeI I I akEleV=163.kv' I I I I I I I I I I I I I I I I I I I I I I I I ILI t I I ,SW ra e_11 !971I cfl 2 !1!_._ 1 I I I I I 1 I I I I I I I I I I 1 I I I I I I I I I I I I I I i I i I U I i I I I I I I I I I.. _.L_._.I I 1 I 1 I I I I I I I I I I I I I I I I I OI I I I I I I I I I I I I I I I I I I 1 I I I 1 I I I I 1 I I I LL 1 I I I I I I I I I I I I I I I i I I I I I I I I I I 1 1 I I 1 I I I I I I I I I I 1 I I I I I I 1 I I I I I I I I 1 I I 1 I I I 1 I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 1 _ _L _..I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I 1 1 I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I 1 I I I 1 I I I I I I I I I I I I I I I I I 1 I I I I t I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I 1 I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 I 1 I I I I I I I I I I I 1 I I I I 1 I I I 1 ! 1 1 I I I I I I I I 0.02 Cfs I I I I I I I I I I I I I 1 I I I I 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 2829 30 31 32 33 34 35 36 Time (hours) 58 Center • Andover, ` Drainage Report Appendix B — TSS Calculations The proposed design exceeds the Department of Environmental Protection requirements for Best Management Practices and water quality. The roof runoff is collected and discharged through a rain garden and then into the subsurface underground system and carries no parking lot suspended solids. The areas of the parking lot are broken up and collected into proposed Stormceptor units which by themselves remove 80% of the TSS. Tabulation for this is included in this section. DeVellis Zrein Inc. May 24, 2019 59 V INSTRUCTIONS: Version 1,Automated:Mar.4,2008 1. In BMP Column, click on Blue Cell to Activate Drop Down Menu 2. Select BMP from Drop Down Menu 3.After BMP is selected, TSS Removal and other Columns are automatically completed. Location: Stormceptor 450i Standard Parking Placement B C D E F TSS Removal Starting TSS Amount Remaining BMP' Rate' Load* Removed (C*D) Load (D-E) G) Street Sweeping -5% 0.05 1.00 0.05 0.95 tQ U) > L Stormceptor 0.80,_ 0.95 0.76 0.19 0 E W 0.00 0.19 0.00 0.19 U 0.00 0.19 0.00 0.19 V V 0.00 0.19 0.00 0.19 Separate Form Needs to be Completed for Each Total TSS Removal - 81% outlet or BIVIP Train Project: North Andover Adult Center Prepared By: DeVellis Zrein, Inc. *Equals remaining load from previous BMP (E) Date: 21-May-19 which enters the BMP Non-automated TSS Calculation Sheet must be used if Proprietary BMP Proposed 1.From MassDEP Stormwater Handbook Vol. 1 Mass.Dept.of Environmental Protection AAult Center • Andover,- ' Drainage Report Water Volume Calculations ® Infiltration Volume Calculations DeVellis Zrein, Inc. May 24,2019 61 Computations Sze Planning Civil Enjineer,q Ldmpe Architecture Po Box 307 50x5ouSk 93.8583 p Project Adult Center Project# 2G1S-385 SOB393.BS83 phcre � 1 derelt'sue;n.«•m Location North Andover Sheet 1 of 1 Calculated by JJD Date 5/21/2019 DeVellis Zrein Inc, Checked by TOG Date 5/23/2019 Title Recharge Calculations Methodology MA Department of Environmental Protection (DEP) Stormwater Management (Volume One) Design Criteria: Based on the Site Hydrologic Soil Group: Hydrologic Soil Group Volume to Recharge (x Total Imp. Area) A 0.60 inches of runoff B 0.35 inches of runoff C 0.25 inches of runoff D 0.10 inches of runoff Recharge Area Required: Total Incease in Impervious areas = 0.482 acres (21,000 square feet) Required recharge Volume=21,000 x 0.25/12 = 438 cubic feet Recharge The dead storage within the infiltration system consists of 6-inches of stone above and below the pipes Area This dead storage infiltrates into the ground and does not flow from the site. Provided: System area and volume= 40 feet long x 28 feet wide with 12" pipes surrounded by 6"inches of stone equals 2,000 cubic feet Voulme within two rain gardens below overflow outlet= 800 cubic feet Recharge Required = 438 cubic feet Recharge Provided = 2800 cubic feet Recharge provided in excess of 6 times the requirement Note that the dead storage is in addition to the exfiltration flow into the ground during the storm events. 62 Center • Andover, ' Drainage Report Appendix C — Test Pit Data DeVellis Zrein, Inc. May 24,2019 63 TEST PIT (DZI-1 � TEST PIT (DZI-2) TEST PIT (DZI-31 SOIL SOIL SOIL SOIL SOIL SOIL HORIZON TEXTURE HORIZON TEXTURE HORIZON TEXTURE 0" O„ 0" 811 AP SANDY LOAM 12„ AP SANDY LOAM 10„ AP SANDY LOAM 22" B,v SANDY LOAM 20" B,v SANDY LOAM 22" B,H SANDY LOAM 42" ESHGW 43" ESHGW 35" ESHGW 2C SANDY LOAM 2C SANDY LOAM 2C SANDY LOAM GRAVELLY GRAVELLY GRAVELLY 96" I— _ 88't ��IIII� 99" I������ GRAVELLY TEST PIT TEST PIT (DZI-5 TEST PIT (DZI-61 SOIL SOIL SOIL SOIL SOIL SOIL HORIZON TEXTURE HORIZON TEXTURE HORIZON TEXTURE O„ O„ O„ 7„ AP SANDY LOAM 10)) AP SANDY LOAM 12„ AP SANDY LOAM 191, Bv, SANDY LOAM 20" B„, SANDY LOAM 18" Bv, SANDY LOAM 38" ESHGW 36" ESHGW 38" ESHGW 2C SANDY LOAM 2C SANDY LOAM 2C SANDY LOAM GRAVELLY GRAVELLY GRAVELLY 96" 9811 -III= 96" TEST PIT AND PERCOLATION TEST WERE PERFORMED ON APRIL 11, 2019 THE TESTING WAS PERFORMED BY JAMES J DEVELLIS, P.E. / REGISTERED SOIL EVALUATOR se 571 OF DEVELLIS ZREIN INC. OF FOXBOROUGH, MA 64 Adult Center Andover, ' Drainage Report Appendix D — Site Plans REDUCED AND FULL SIZE PLANS PROVIDED WITHIN THE APPLICATION SUBMISSION PROVIDED BY THE PROJECT ARCHITECT THESE REDUCED COPIES ARE PROVIDED WTIHIN THIS REPORT FOR CONVENIENT REFERENCE PURPOSES DeVellis Zrein, Inc. May 24,2019 65 Site Development Plans SITE NORTH ANDOVER ADULT CENTER 1 SURRY ST. (MAP 74 PARCEL 25.1) 477-505 SUTTON ST. (MAP 74 PARCEL 24/23) North Andover, Massachusetts SCALE 1= 500' MAY 28, 2019 List Of Drawings Cover Sheet Existing Conditions Plan C-1 Layout and Materials Plan C-2 Grading and Utility Plan Owner/a.ppliccnt C-3 Planting Plan TOWN OF NORTH ANDOVER 120 MAIN ST. C-4 Details Sheet rn NORTH ANDOVER,MA C-5 Details Sheet Civil Engineer/Landscape Architect DeVellis Zrein Inc. C-6 Details Sheet P.O.Box Photometric Plan Foxboroughgh,MA 02035 508.473.4114 DEVELLISZREIN.COM Architect CATLIN+PETROVICK ARCHITECTS,PC 51 RAILROAD STREET,SUITE 130 M KEENE,NH 03431 m��` Tw`Iw'"a.nrol Surveyor Precision Land Survey 32 Turnpike Rd. �tiw Southborough,MA 01772 ZONING DATA RESIDENTIAL 4 1 SURRY DR BUSINESS 2-477-505 SUTTON ST. y Rw.u. w. w. .r cyan w. Ww. w. w. Y t 0 0 A a- Bu. -11�, MFMEET — --------- PROCRC Lr)ru5 MAJI 1-1 r-111, — -, 11 I�, Ile— , T, Val 77 Yr, T.1 ; 1-.7 t—r'".1 Ws rx. alll, cu, 1�1—v.alt. Ive ,_-QAV( Im lzpu lrr MlyP PR[ l LI Op—, E .�4T fIV, i Mo %1I - pIr11A — IrMT ILI ww­vs tm=q, IWT N4L.11.111 IC,'( I-­­V4 oA Ns i^ Nl-—- I= V,.7 1nm M I—, --,I, ot-,w—' I` _ll 4.17c MMI (E(FND ANQ SymgnIS-. GER4FRAL MITY NJ)TER_ W.PSN urv. 61 M . V, a,Y Al%i�l Mt j u.N zii? ­­M IZ � Z kv I CL Ia , Lail M=l 14P�� Am w im, Mi MT .AM I41m; cn LD 7 t�lplo P:­c Rr R3)k A T�­ r. cD c-L r.M.1'.1� LAYOUT AND MATERIAL NOTES L, CONORIONSIN'FOPiMTiONISREPROO:ICEOFROMTHESURVEYPRFPaREDBYMORINRMEP.ON NORTH �Qo�FDAN RS,N NDI50AEDNE¢MBA,5.tB1n. ANDOVER 2. CONTRAATiR SHALL NO NIISSAFEA DTHEP PROPER PPEBa—HORHESURVEYREFERFNCEHILITY THE NDTI DIG FEAND THE ALA HDP1ilE50RRE E�,n ADULT CENTER GENPPANAl ICDDES To 11UM OF THECON,PAcigtmCOMaR THE PROPERAUf`DN AUTHORITIES 'NA"BE THE CONTPACTOF, RE 1. GONTRACTOR(.)SWd AMILIAREE THEMSELVES—ALL CONSTRUCRON DO-11EHIS, SPEQPIGTIGNB,AND SHE CONDITIONS PRIOR TO BIDDING AND PRIOR TO QMSTRUCTDN. a. I PANCIES BETW W IFICAT EEN DRANGS.SPECIONS,AND SITE CONDRIDNS SHALL BE REPORTED MEDIATELY TOTHE OLW EA'S PEPRESENTATNE FOR CLARIFICATION AND REBOLOFION PRIOR TO BIDDING OR CONST[uCT10N. ALLWORRCONOUEEEDWITHIN PUBLIC RIGHSOFWAYSSHAD.—FCPMTOTMEREOUIP-5AND NORTH ANDOVER,MA SPFCIFTCATIONS OFTHE T—OF NORTH ANDOVER. S. SEE AB<HIrtCNRAL DRAWINGS FOR ExACf BUILDING DINENSIONBAID ALL DETAILS DEN11000u5 TO THE BUILD INGI—OING SIDENALKS,RA—,LrtiLItY I—IN<C IDFATONG,WALL PAEFS,CONOREIE D000. _.-._ ------ -_-- - ----- ------ PaDS,ROOF EPAINS,ETG ... 4 TN�AERI`ECA�NS II DISAIRLITIES nR(AGA)AE ESSIBRmM GUGETUNesw'Lv`Hi rvia IS MORE BI AND - LEGEND STRINGENT. -- PROPERTY LINE 1. FOLLT'JINGIFYOUTCAITERIA SHALLCDNTROLUNLESSOTHFRVJISENOTEDONTHEPUN: TOOUISICE FACE OF BVIt➢iNG. - M A._ LL DIMENSIONS ARE TO FAZE OFCUSB Ai GIIREP.TINE SITE LIOHTNG ALL DIMENSIONS ARE TO C@REROF PAVEMENTMARKINGI ALL""TO N PROPERTY LINES ARE PERPENDI ,AR TOTME PROPERTY LINE UNLESS OTHERWISE NOTED. .-__.._ __.__. _.._.._ -..._.. - __-__- ____.__.. __.-__ -_-._ ___- _..._ s. FOR LAYOUF AND DIMENSIONING OF BUILDING:,SEE ARCH—TURAL DRAWINGS. -- VCRYIGI GPANRE NRB 9. SUEENED ilUGES SHOW FYISTNG CONDITIONS.WHEREE%ISTING ED DRIONS LIE UNDEP OR ARE _..__ SU TTON STREET n CEOM eDFRD iCNCC IMPINGED UPON BY PPOPOSED BUILDINGS AND/Bt SITE ELEMENTS.THE—INS C9IiDITiCN WILL BE - - HD,OVED,ABANDONED AND/OR CAPPED OR DEMOLILH®AS REQUIRED. - -- - --.._ .--- ----_—(PUBLIC ��-FTAGPOLEFINALLOCATIONTBC - 62' WIDE) PAoCo - �:� TPRPNe, j NA - d mT PwB mN"ND vM ! �j/ �� YLDIYGL mmL �rt�`irtT.a.a - .I. :, PAwoR— x Sn" P�"wwrT`n"P.1C j c°i6AooLx`O1vTu I r 1 .�•�� G'RDIL LBNOf2 • NLY9Ld a, jIe-B• 1 o f n• e• a e e n• B• 1 '� � `�R. ® DZ I � e r j R v ! .EVR, 1 1 " -_ X DeVellls Zreln Inc. w x j 5¢Pc%oRN P C fp 9 IC 1 � w LAYOUT AND I i -- 1 MATERIALS --------------- ..................J PLAN PBM"` NOLO �Rh PH f C_1 �s»DYA, GRADING AND UTILITY NOTES NORTH 1. EXISTINC CONDITIONS INFORMATION IS REPRODUCED FROM THE SURVEY PREPARED BY MORIN CAMRW OF DANVERS.MA AND 15 DAM NOWUBM 3010. AN DO\/EI'f Z HE TO THE START CT ANY EXCAVATION FOR THE PPOJELE BOTH ON TH OFF ADULT CENTER THE 511E THE CW-1IN SHALL NOTIFY DICSAFF AND BE HAW B EO MTH A t! A. AR— ... A KUNDFR INDILATNC THAT ALL EXISTING UiiLITI6 HAYS BEEN LOCATED Av,\,f R ED. 1 ONTRACI.TO ADJUST ULLITY ELEMENT MEANT TO DE FLUSH MTH GRADE (BEAN—OUTS,UTILITY MANHOLES,CATCH BARNS,INLER E10.)THAT IS ( PLAN SMOR HOTITE WORK OR GRADE CHANCES.WHETHM SPEUMCALLY NOTED ON 4. tALL CONSTRUC710N 10 BE DONE IN ACCORDANCE MIiH NORTH ANOPT OF PUBLICA. NORTH ANDOVER,MA ALL WORK TO BE DONE"IN PUBLIC RIGHT-OF-WAYS SHALL CONFORM TO THE �41 REOUIREAENTS AND SPEGFICATONS OF THE TOWN OF NORTH ANDOVER.MA. S THE LOCATIONS OF EMSMNC UNDERCROUM UTAITES ARE SHOMN IN AN I APROXIMATE WAY ONLY AND HAVE NOT BE VEN INDEPENDENTLY RRM BY THE GRADING AND UTILITY LEGEND O Eft OR ITS REDRLSFN—W. THE CONTRACTOR SHALL OEIE—A THE EXACT LOCATION OF ALL EXISTING UTILITIES BEFORE COMMENCINGDAMAGES N-AND --".... .. ..... ___ __........___— --__._...._ AGREES m 0E FULLY RESPONSIBLE FOR ANY O ALL DAMAGES YMICN MAY BE _. -- -- - OPERtt LINE AUL UNDERGROUND BY THE GOIlRAC10R'S FAILURE TO FXACT.T LOCATE AND PRESERVE " ALL UNDERGROUND UTILITIES G WHERE AN E%ISWC UTIUTY 15 FOUND M CWNCT WITH THE PROPOSED WORK. LINE THE LOCATION.ELEVATION,AND SIZE W THE UOUTY SHALL BE ACCURATELY DETERNINM WITHOUT DELAY BY THE WNTRACIOR,AND THE(NM MATION FVPNISHFD TO TH EER FO E ENGNR RESOWTA'OF 1HE CONFLICT. ]. THE CONTRACTOR SHALL ALTER THE MASONRY OF THE TOP SECTION OF ALL '- - ' __ -" III II II ETOCIRIC EXISTING DRAINAGE STRUCTURES AS NECESSARY FOR CHANGE N GRADE AND -.- RESET ALL WATER AND DRAINAGE FRAME&GRATES.AND BOXES TO THE PROPOSED W.S G. THE fANTRACTOR SHALL MAKE ALL ARRANGEMENTS FOR THE ALTERATION AND �� -- ADJUSTMENT THE ALL GAS.COMPANIES T:LEPHWE AND ANY OTHER PRIVATE �- SIH GT CA1CIq.AWN 2 UTILITIES BY THE iJTIUTY CWPANIES R.tnm Tns w t S. ACONLL UTILITY SHALL MAINTAIN.RE ADJUST TO NEW ENISH GRADE.AS NECESSARY ALL UTILITY AND SITE STRUCTURES HANG SUCH A3 LIGHT POLE&SIGN POLES. ~%/ter w MANHOLES.CATCH MAINTAINED T HANG HOLES,WAhR AND CAS GTS.NYORANtS, ® DRUM HAMHOL ETC.FROM MAINTAINED UTILITY AND SITE SYSTEMS,UNLESS OTHERWISE NOlEO AjMS - I r) C _ OR DIRECTED DY OWNER'S REPRESENT.ATIW - `y5 ,�� G'0 J - ROAD DCPOI N - ® W:WtT YAHNCTE T v 10. ALL SRU..PIPE SHALL BE PM PER A51M OJ034,SOR-33 AND AS.Ot>B4 - �T I ' $IINF)6 ttP. 1RAVWTXRYFR WITH flUBeER CASKET JOINTS. - 11. SITE UCHTHIS IS SHOWN W THIS PUN FOR COORDINATION PURPOSES ONLY. �- 1ESZ TnJo -� a � O aF H ouT REFER TO ELECTRICAL PLANS FOR EMCT TYPE AND LOCATION. / n1D Y 12 REFER TO ELECTRICAL PLANS FOR SECRIONS AND DETAILS THE VTRJtt DUES -.GM- WOE 10 DRUM j--� - ` °°' }t f o< 1 i Inm I pF GIuSc uy I_ 13. BA- AREAS OUTSIDE THE LIMITS OF PROPOSED WORK DISTLROM BY THE CONTRACTOR'S OPERATIONS SHALL BE RESTORED BY THE COMRAOOR M THEIR D µj r (' S' � 1", ORIGINAL CONDITION.AT THE CONTRACTOR'S EXPENSE, , \ 14. REFER TO ARLMTECNRAL PLANS FOR PROPOSED LOCATION OF UTILITY SERMCE ) J' STUBS AT BUILDING _- / z H r':/ J ,r 1f4'(>L (•r 1(( I;J TI IS, THE LOCATW,SIZE,OEPTH,AND SPECFlCATIWS MR CONSTRUC—OF PIRVAIE \ I I /] )� 0➢4 OyITIUTY SEP—SNALL BE INSTALLED ACCORDING TO THE REQURDXENTS (�PROWDM BY.AND A➢PROVED BY.THE RESPELTW UVJTY COMPANY(GAS. / F TEIEMHWE ELECTRICAL) FINAL DESIGNAND LOGTWS AT THE BUILDING WILL ) bk Y, ~ 1'ODYE Y. BE PROMOED BY THE ARCHITECT. THE CWTRAttOR SHALL COOPDNAIE THE / STAUA TH TIW W E UTILITY CONNECTIONS WITH THE RESPECTW COMPANIES L. PPIOR TO ANY UTU1Y CONSTRUCTION. \ 1G. A LL CEMENT UNM DVCTU IRON JGINR AT FRTINCS(CUSS SZ)VALVES,AND .�� '� R g -- HYDRANT LATERALS SHALL MECHANICAL MINT WITH NEOPRENE GASKETS. MINES AT OTHER LOCATIONS SHALL BE PUSH-W TYPE MM NEOPRENE , STNT)IETC RUBBER WA ER ALL WATER GATES SHALL OPEN AS PER dtt o D 1 CRWNDXCOME ALL WATER UM O SHALL HAW A RATION Of T FEET OF f L GROUND OVER AND A MINIMUM OF 10 FOOT SEPARATION FROM THE BENFR _ SRTEM. WATER AND SEWER pHOSWNG&THE WATER LNE SHALL BE �E I ENCASED IN W FEET ON INCHES aF CONCRETE FOR A DISTANCE W 10 ON EITHER WOE OF THE CROSWNG 11 PROTECT AND MANTAIN EXISTING W-ATE DRAINAGE STRUCTURES AND PIPE U FT I R�Rlia UNLESS OTHEAWTSE NOTED. I DMHm] I 11 I / t0.5.T0 W4 1& WHO PROPOSED GRADES MEET EXISTING GRADE&CONTRACTOR EN—BLEND �, hf JVL��-M - 3'----. / TT R T I �• GRADES M PROYOE A SMWTH VANWTON BETWEEN EXISYNG AND NEW WORK. I- ONDINC AT TRANSITION AREAS MU NOT BE ALLOWED, I I' 10. CONTRACTOR SHALL MAMTUN POSITIVE OR—AWAY FROM ALL II-1.0 `�W ND I w FOUNDAIIWS,STRUCTURES AND PUNTING BONS. DRAIN 0 — I b� A. MAXIMUM N.T IN OISNRBEO MESS SHALL NOT EXCEED 3:1,UNLESS N 1B0 1SG /��IMrt OF WMN P^KwBP'•V¢ OTgAMSE NOTEp. U. _- Ix Aq&T CENTER 1T9. 7 fE5 SC_46O WN V /.m -- I D Z 1 Z. ENSURE ALL CUSTNG TO REMAIN),AND PROPOSED MANHOLE COVERS PROPEPLY R iMt IDENTIFY UTUTY DERNCED. � /' '��-GW WT�PIA. m SMJIIeTRI CONTRACTOR SHALL VERIFY EXISTINC DUDES AND NOTIFY MEFS 'L h 543 Owe 1 % I 24. SCREENED IMAGES h aID J ° Uf #! AY DeVellis Zrein Inc. REPRESEMATIW OF ANY DISCREPANGES 21 BITNNOUS CONCRETE ELEVATIONS AT CATCH BARNS TO BE 1/4 NCN ABOW DNHI8= 1 • ' 1 �' RIM ETEVATIW SHOWN FOR CATCH. - LES SHOW EXISTING CONDITIONS WHERE F AND CWOTONS UE _ UNDER OR IMPINGO UPON 0Y PROPOSED BUILDINGS AND/OR WIE ELEMENTS, ' O THE EXISTING CONOTIW MLL BE PEMOVW, ABANDONED AND/OR CAPPW OR DFMOLISRED AS REWIRED. � GXB45C4SO; � •_•_ _ •_•_•—•_•_•_•—•—•—•_•J GRADING AND UTILITY PLAN I a 11 ' UL:TP. RD P PLANTING NOTES PLANT SCHEDULE FOR STORMWATER MANAGMENT AREAS NORTH 1. ETUSTNC CONDMONS INFORMATION IS REPRODUCED FROM THE SURVEY PREPARED BY MORRIN ANDOVER CAMEMN OF DANVERS,NA.DATED IS NIRADHEIIER 2.18. PLANT SCHEDULE SYMBOL BOTANICAL NAME COMMON NAME OTY SIZE COMMENT 0. THE LOCATIONS OF UNDERGROUND UTIUTES SHONE ARE BASED ON THE SURVEY REF9tpcm NY ADULT CENTER ABOVE THE CONTRACTOR SHALL CONTACT DIGSAFE AND THE PROPER LOCAL ALMICRITES OR N AYAYF3E—AAA UDUIY CUAPANIES TO CONFIRM THE LOCATION OF ALL..NO UTLIRES BEFORE STIABOL BOTANICAL NAME COMMON NAME OTT SIZE COMMENT COMMENCING WORK NY DAMAGE DUE TO FAILURE OF THE CONTRACTOR TO CONTACT THE AUtFA MypglR SWAP A-- 13-15 PROPER AUTHORITIES SHALL BE BORNE BY TIE CDNTRAGIUR. 1 CONTRACTOR SHALL BEGIN MAINTENANCE IMMEDIATELY AFTER PUNTING AND YDLL CDNTNIUE O[OF GUGARTA TBMCANBAS I 1HDRMIIS.—OGST I/2•CAL GA QMIIXA ALRMUA SIILERSItIT UNTIL FINAL WITTEN ACCEPTANCE OF PLANT MATERIAL PA PIATNS AIfFWUA -I.PLWE 1AEE }-3 IR.-GL IVACWIIW ADOUSTOFWA L w@91 DLLEBEIXR -} E —A SEAHATA DRFFNYAX ZFICPU 21/Y-3 t L AL°ISW pBNdR WSX gllfHEIWT T2-15 A. NDSCAPE ARCHITECT TO FUG ALL TREES TO BE TRANGPNTm PRIOR TO CONSTRUCRON STAR ­AcO E AMwRwER caxADDlm slAmpq 17'NL ASItA NDVFA-ANDIU. N.ENWLA ASIEA tuL NORTH ANDOVER,MA 5. CONTRACTOR SHALL VERIFY ALL TREE REMCVLS AND/OR TRANSPUNTS WITH OWNER'S GC CDTLS GNARBES EA_RED BA e-3 Hi. DLYP CA Gill-C FE101SLY. PD STLY/IYA_ 1 W. REPRESENTATIVE PRIOR TO CDNSMUCTGN START. LI OU NDAIRNUS VRmHNS MIRE PRINCETIT£ RUMP Ei=IR6 m RLUE MG BDS GAL LL AWAY G. CONTRACTOR SHA MAINTAIN POSTYE DRAINAGE FROM ALL BUILDING FOUNGATGNS HV 4M _VA I., MTCH HAIEl OI I G'1' STRUCIVRM AND PNTNG TmS -RUSGOES BLIND FDA BASIN ILStgNN PINE 15•HL SUPPLEMENT PLANTINGS IN RAIN GARDEN NTTH THE FDLL°WINC SEED MORPHR E ON D THIS DRA 3. MA%KNM SLOPE WITHIN DISTURBED AREAS SHALL NOT IX1—}:1.UNLESS OTHERWISE NOTED. TO CO BLEN:Sn NU H—H.WCR GAUGS SMRffR ENpIL59AlYER NTRAN4A }CAL R. E PLEM ALDL CONTRACTOR PLANT RIGS O SHALL P NG MAlER1At5 IN GUANTTES SUFFICIENT NU T URE P1F'E55 0UE PRNQE4 HOLLY H, NEW FECUND WETUNp PLAHIS.INC. PLANTING Nav En antl Emalon LonUPI/Raalomllm Mh Fm Datmlbn Boalna A. PC RIIOOmDARON(MEWED MIt2 RHWDDDADDN 21-JII'M. 40iat Saa �••� PRWEATY U. ALL MATERIALS SMALL CONFORM TO GUIDELINES HE E GIUNES ESTABUSH BY T AMESCAN NURSERY VD VR DE RAIW'M OSE RY MUR V AMRDA'AODD NBURMN }CAL i W OF SEED FOR THE ENTIRE RAIN GARDEN/APPUCATON THE LATE AND LANDSCAPE ASSOGATON. NNAAI SPRN./SUMMEL 10, LA ALL PLANTS SNALL BEAR THE SAME RETATONSHP GRADES TD FINISH GRACE AS TO ORIGINAL GRAD EGA°AR EGWACEA W[a w T P_TAR C =_"L Q OROUN FR/PERENNIAL REFINE GGGNG' UWOP[WSCARI L T TGI NAIVE SEED BLEND FDA ALL O1Hm UMN AREASW�HARD FESCUE 11. ALL PLANTS TD BE BALL3I IN BURLAP OR CONTAINER20D• PAL PF]M6EIi, AIOFEN I'D.TIRE w— OYAFF FDAGAIN W55 25S PER.RYE i 5M U�BLUESMA 12. MU ON FOR PUNTED AREAS TO BE ACED PINE BARK PARTIALLY DECOMPOSED.DARN BROWN CWwON vTRTE SIR.O4 RA SNA.—HONG COLOR AND FREE OF NOW CHIPS THICKER THAN T/A IN.. CY 9 ALY 10 1 GY.OR mUIVALENT. FERTUZEA ADDED PER RECpA111ENOm RATES OP SOILS - ANALYSIS I0. THE LANDSCAPE CONTRACTOR SHALL GUARANIES ALL PLAT MATERIALS FOR ONE II)FULL — -- _ YEAR ROM DATE°`ACCEPTANCE SUTTON STREET iS ALL PLAT MATERALS ARE SUO.I—C TO THE APPROVAL OF THE LANDSCAPE ARCHITECT,AT _ THE NURSEAREAS O,AND AT THE SITE __ (PUBLIC — 62' WIDE) l ID. ALL AREAS OF TIE SITE CWIGHEDE HAVE BEEN AMUMDEP AND NOT OTHERNISE CEVEfLPED '" SHALL 8E LAAMm AND SLT:DEO MITI A MINIMUM DEPTH OF 6•DEPTH tOPSGL -- "' ---- "- � �- �- - T. CVEgERW TREE 1] PUNT SPECES AS INDICATED IN THE PLANT UST ARE SUGGESTIDNS ONLY. FINAL SELEGTON OF SPECIES SHALL OCCUR AT THE THE OF PLAT PURCHASE DEPENDING ON­ILA—W. PUNT SIZE AND OUANRTY SHALL NOT CHANCE PATHOUT APPROVAL OF OWNER'S -- - REPRESENTATVE GGGG—TR- ........... 1 -_ UD 1 o: m q A WK F S t a j Pn 1 + �Q D DZ 1 DeVellis Zrein Inc. + j - + 41� w i Of + .••.: ! 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LL SLOPES AND ACCRCCATE RAPE CWRSE AOAEWIE B.ICE 1 FNSRNS 10 CON—M A• ANO 4AAB FEOIPFENENTS. NCS [GTC CA. MTEnf LENIXor NN0.�MT AT TOPS OF' RAMP AND AT DACN OF WAU(AT _ CWRSE MM NE BROOM FlNISN ON MMP AND BNE AOPES PERPENpCULAR CWPACIEO.UOMAOE MEN V NNG 1 E.U.NA1 WAgMW3oN5 A.FRON 0K OF F. H016 CPOACiEp SLBgAOE D.INC.—GVRB EFNCIN AS REWtttEO i0 MEET CWE PPONDE IIWiT BPOW FBlISH P[IIPENDIwUR To THE tFAFFlC ROW WEmACIID SUBCPADE UNLESS OTIFRRiSE NOTED T WAY—T OF U. MN[LCMAIR-1 M CNC�iRAMJTnONT AOPGw IDlSUE NEAWPWTT ply OMSE W$µT PART OF THE MNEELUTAM 1N NP,FyCwDINO NNB B TRAIEITIWS,TO BE LOCATED CUTSNE W TIE.—Am CEMENT CONCRETE SIDEWALK BITUMINUOUS CONCRETE PAVEMENT VERTICAL GRANITE CURB CURB CUT TYPE 'A• PFECAST CONCRETE PAVER TO BE SET M' T/0•nLE SPACERS CA SMD OETW@I JOINTS i•54Np SOEWALI( SETTING e[O CEO-lE%iltE C' u nR¢O Puc¢O tVO.c. LO�ct�tS"PIN— Z C�".t.•:C��'vm:.�:,.�,. BLOMWUCEOPIITm NECK F • USE UCTAL ECCE NESTRAll T - &T—R.— .......... TCO 'ti.+iti+." BHCPE P s W NOT AWT ' CONCRCTE SET TOP 1/2•BROW TTU lOP OF PAKAS y g ' ilD9i Cu. Cu1Po91E YEUDN CIECTAIXEAT Mo, �TnD[MIN. _ GRAVEL.BORROW AA101 AT OSJFAiAa OWN K MA 1� HANDICAP CURB CUT TYPE 'B' PRECAST CONCRETE PAVERS SILT SOXX FLAG POLE rs. DZ (� " NA DWellis±rein Inc. AVO NIL O[0[TWNNTO DY UOIm On�D�ND MNugPAEgAN. REARPA- >W SRN PANEt RJ13H 4W NTEp 10 IA42 iipKAt DOB P4E PqE DA¢A•A WACR FRONT_ 91PPORl'POSiS ON..F.LOP,µD BACX �—TTP 55wan pµFl, it LL M BLE NECRWS SHALL DE FULL Ft A�css u InMN NT3DE0 NO 1OOND RUSH MD SNOOIN Sot lTuypP�� yq n > iY A 1•T1p.rt'- ��aAK HAOJT�N— PRESSURE-SENSInVE MNYL(NfMI— _ t —NINO—AND COPY TO BE O MKwk 5 p�4. —CC—W.AI ar OB I REPRE:NTAnvE :iro. —NAxoluP�Acc . 2•SWME AWMMVU POST � �'•"• AtWOR BO.T AS IEWI® b TE tlMWACNA@ FAA. CnAOE [OWAI.SEt 9B:RGA7� EIE FOOIINcTOP OF wNL,+ETE mom c s• "" RB:e D x SITE DETAILS SHEET W_,_ OEtOwS5FEBAg OF P AM'YVNT CquAC20 SWm+ [ .uxrnLu l4NTU®mxOItR BA2 mnAclm-� ,I` Dmauz CC- C-4 HANDICAP PARKING SIGN HANDICAP PARKING LAYOUT LIGHT POLE BASE =.Z"Z—o— NORTH A.: ANDOVER ADULT CENTER NORTH ANDOVER,MA 24 S U MI-11-11, UFOA CATCH BASIN (CB) DRAIN MANHOLE (DMH) SEWER MANHOLE (SMH) TAPPING SLEEVE AND GATE A.n—EE—F.A LAOS OUT IN—FOUS OF.NEl.13E LANDSCAPE ARCHITECT /—,—OF--SEA. —ano.--OF PAIN —EN .n. SEE SLOPES V.1— L'On ALLSWALES SEDGES AND--n— L"L -IARGE SHRUBS —ES) max vMc ERusx m SFOOE —NE STC,450i Procist Concrete Strnn..13toi I-1A.Fe(.1— (450 U.S.Gallon Capacity) I on UN.-Fe. ".-n EQUAL) /-CO1..000U*1EEAICN 9MTE Sun ASE TO M GARDEN PRESSI.BLEND OE SAND.See.INO CONPOST S.- A o S E =R'CV= Ir I.Foo"E. A.-ON S"OF"1" .3— 'nE CONFR—EFLO-C% N ' TOTAL OF 14 MES 1.SIM pta(romp,#I- JOS go A.ACOU—TE-11r,NAX GSM RETAIN-1- I TO REVIEW PLANiiNG UST XLiN LANDSCAPE...OF A.EOORSSN.X ALL MEES..-L.E.AMLAOIUW AND SCHEDULE OF INSFAUA�—PRIM TO MKWM W— O WC me UTILITY TRENCH UNDERGROUND RECHARGE SYSTEM RAIN GARDEN no,N— DZ F.* PrtOVIDE 2a'to.ACCESS IF RS[tPw to Sealol.e5e�l can PINOS TO CAST WON DeVellis Zrein Inc. In noo -j ——————————— T Section Th-Chamber Plan View TEE fi Notes: ff 1.Th.U.Of Findibi.Coneettio,IS R— .,I.. d t The M Oahe(.4 Why Appikoble. SITE DETAILS SHEET The ,C.-Shonld be I'mir-od 0-TO.Wet Dop IFpU and The Go Pert =met the Miming US Potooloe 14995148, J5495331,15725760.15753115.FZ4911 J61765.16371690. on-A.— L ——————————- rim SECTION PLAN CAM C-5 STORMCEPTOR 4501 0&1043: me 2000 GALS. GREASE TRAP CenterAdult • Andover, ' Drainage Report END OF DRAINAGE REPORT DeVellis Zrein, Inc. May 24,2019 73