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Zero Prescott Full Stormwater Report - Comprehensive Permit - Application - 0 Prescott Street 10/21/2025 STORMWATER MANAGEMENT REPORT FOR EAST MILL RESIDENTIAL DEVELOPMENT 0 PRESCOTT STREET NORTH ANDOVER, MA 01845 PREPARED FOR: RCG, LLC 17 Ivaloo Street, Suite 100 Somerville, MA 02143 PREPARED BY: C IVIL D ESIGN G ROUP, LLC 4 HIGH STREET, SUITE 155 NORTH ANDOVER, MA 01845 DATE: OCTOBER 2025 p: 978.794.5400 f: 978.965.3971 www.cdgengineering.com East Mill Redevelopment, North Andover MA TABLE OF CONTENTS PAGE I.STORMWATER MANAGEMENT NARRATIVE 1.0 SITE LOCATION AND DESCRIPTION…………………………………………………… 1 2.0 METHODOLOGY……………………………………………………………………………. 1 3.0 SOILS & GROUNDWATER…….…………………………………………………………… 1 4.0 POINTS OF ANALYSIS……………………………………………………………………… 2 5.0 EXISTING DRAINAGE WATERSHEDS…………………………..………………………. 2 6.0 PROPOSED DRAINAGE WATERSHEDS…………………………………………………. 2 7.0 PEAK FLOW RATE ………………………………………………………………………… 3 8.0 WATER QUALITY………………………………………………………………………….. 3 9.0 GROUNDWATER RECHARGE …………………………………….………………………. 4 10.0 DRAINAGE CONVEYANCE SYSTEM………………………………..…………………... 5 11.0 COMPLIANCE WITH THE MA DEP STORMWATER HANDBOOK…………………… 5 12.0 SUMMARY…………………………………………………………………………………. 7 II.LIST OF FIGURES FIGURE 1: USGS PLAN FIGURE 2: SOIL MAP FIGURE 3: PRE-DEVELOPMENT WATERSHEDS FIGURE 4: POST-DEVELOPMENT WATERSHEDS TEST PITS III.HYDROLOGICAL CALCULATIONS PRE-DEVELOPMENT HYDROCAD CALCULATIONS POST-DEVELOPMENT HYDROCAD CALCULATIONS IV.APPENDIX-1 MASSACHUSETTS DEP STORMWATER REPORT CHECKLIST V.APPENDIX-2 OPERATION AND MAINTENANCE PLAN (O&M) (WITH LONG-TERM POLLUTION PREVENTION PLAN) 0 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com East Mill Redevelopment, North Andover MA 1.0 SITE LOCATION AND DESCRIPTION Civil Design Group, LLC (CDG) has been retained byRCG, LLC to prepare this Stormwater Management Report for the construction of a residential development and to upgrade associated existing parking areas located on the East Mill campus on High Street, North Andover, Massachusetts(refer to Figure-1). The project includes the construction of a 92,000± square foot (footprint) residential building comprised of 296 units and the reconstruction/enahancement of existing parking areas including curb, landscaping and stormwater improvements within a 6.13± acre limit of work area within the site. According to FEMA flood insurance rate maps community panel number 2500980228G, effective date 07/08/2025, the area of the site to be redeveloped lies within Zone X, which is defined as areas determined to be outside the 0.2% (500-year) annual chance floodplain. The site does not include bordering vegetated wetlands and based on available MassGIS information, the site does not lie within an area mapped for rare and endangered species or certified vernal pools as mapped by the State of Massachusetts’ Natural Heritage and Endangered Species Program (NHESP) or within an Area of Critical Environmental Concern (ACEC). The site also does not lie within a surface water protection district. This study presents a comparative analysis of the pre-development and post-development hydrologic characteristics of the site, and outlines the proposed measures to mitigate flow, provide groundwater recharge, and improve water quality from the site in accordance with local and state requirements. The proposed best management practices (BMPs) one water quality unit and one (1) subsurface infiltration system (SIS) to provide mitigation of the peak flow rates for the 2, 10, 25 and 100-year storm events and to provide infiltration of onsite impervious areas and treat stormwater to the maximum extent practicable prior to discharging off site. 2.0 METHODOLOGY Technical Paper 40 (TP-40) was utilized to source the precipitation values Technical Release 55 (TR-55) methodology was utilized to determine weighted curve numbers (CNs) for each pre and post-development subcatchment area. Weighted CNs are based on ground cover type and hydrologic soil groups (HSGs). The times of concentration (Tc's) for each of the existing and proposed watersheds have been calculated. The areas that do not show a Tc travel path resulted in travel times of less than 6 minutes. CN and Tc values were then utilized to generate hydrographs using HydroCad 10.0, an industry standard software package that develops a hydrologic model based on the SCS method and computes peak discharges from rainfall runoff for urban and rural watersheds. 3.0 SOILS& GROUNDWATER According to the Natural Resources Conservation Service Web Soil Survey (Figure 2), the underlying soils on the site are classified as Urban Land and fine sandy loam. Based on test pits that were performed in August 2025, the underlying soils are primarily a sandy loam (HSG-B), therefore, this stormwater report utilizes a HSG rating of B for both the existing and proposed conditions for the purposes of capturing surface runoff curve numbers (CN). Furthermore, the proposed infiltration best management practices (BMPs) utilize an infiltration rate of 2.41 in/hr, which is representative of the sandy loam soil. 1 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com East Mill Redevelopment, North Andover MA 4.0 POINTS OF ANALYSIS Points of Analysis (POAs) are discharge points or lines that convey runoff from the study area via overland flow or through drain pipes. The pre-development and post-development areas of disturbance drain to four (4) POA’s listed and described below and shown on Figures 3 and 4. TABLE-1: POINTS OF ANALYSIS POINT OF ANALYSISDESCRIPTION A comparison point representing the existing culvert conveying POA-1 runoff from the existing drainage swale towards High Street (POA-2). A comparison line along the westerly portion of the limit of work POA-2 adjacent to the High Street/Prescott Street intersection that receives runoff via overland flow. A comparison line along the easterly portion of the site that collects POA-3 runoff via overland flow and discharged to the abutting property. A comparison line along the southerly portion of the site that collects POA-4 runoff via overland flow and discharged to the abutting property. 5.0 EXISTING DRAINAGE WATERSHEDS The existing watersheds are delineated based on topography, physical characteristics, drainage networks and limit of disturbance within the site limits and collect and direct stormwater towards the POAs. There are potential upstream areas that flow onsite, however, these areas flow through the property are not subject to be captured into the drainage or stormwater management system, therefore, these areas have been excluded from the stormwater analysis. As such, the total study area for the site is 6.13± acres and is divided into four (4) pre- development watersheds as described below: Subcatchment EX-1: The 2.69-acre watershed is comprised of rooftops, pavement and grass areas. Runoff travels via overland flow in a southerly direction towards POA-1. Subcatchment EX-2: The 2.68-acre watershed is comprised of pavement, grass and wooded areas. Runoff travels via overland flow in a westerly direction towards POA-2. Subcatchment EX-3: The 0.38-acre watershed is comprised of grass and wooded areas. Runoff travels via overland flow in an easterly direction towards POA-3. Subcatchment EX-4: The 0.24-acre watershed is comprised of pavement, grass and wooded areas. Runoff travels via overland flow in a southerly direction towards POA-4. 6.0 PROPOSED DRAINAGE WATERSHEDS Similar to the existing watersheds, the proposed watersheds are delineated based on topography, physical characteristics, drainage networks and limit of disturbance within the site limits and collect and direct stormwater towards the POAs. This area is divided into seven (7) post-development watersheds described below: 2 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com East Mill Redevelopment, North Andover MA Subcatchment PR-1: The 0.69-acre watershed is comprised of pavement and grassed area. Runoff travels via overland flow in a southerly direction towards POA-1. Subcatchment PR-2: The 2.47-acre watershed is comprised of pavement, grassed and wooded areas. Runoff travels via overland flow in a westerly direction towards POA-2. Subcatchment PR-2A: The 0.24-acre watershed is comprised of rooftop area. Runoff is collected via roof drains and discharged into the SIS. The outlet associated with the SIS flows towards POA-2. Subcatchment PR-2B: The 0.20-acre watershed is comprised of pavement and grassed areas. Runoff is collected via the onsite drainage system and discharged into the SIS. The outlet associated with the SIS flows towards POA-2. Subcatchment PR-2C: The 1.88-acre watershed is comprised of rooftop area. Runoff is collected via roof drains and discharged towards POA-2. Subcatchment PR-3: The 0.35-acre watershed is comprised of grass and wooded areas. Runoff travels via overland flow in an easterly direction towards POA-3. Subcatchment PR-4: The 0.31-acre watershed is comprised of pavement, grass and wooded areas. Runoff travels via overland flow in a southerly direction towards POA-4. 7.0 PEAK FLOW RATE MITIGATION The stormwater management system is designed so that post-development peak discharge rates do not exceed pre-development peak discharge rates for the 2-year, 10-year, 25-year and 100-year, 24-hour storm events. Peak flow rates for the pre-development and post-development conditions are illustrated below: TABLE 2: PEAK FLOW RATE COMPARISON POINT 2-YEAR STORM 10-YEAR STORM 25-YEAR STORM 100-YEAR STORM OF EVENTEVENTEVENTEVENT (3.15”/24-HR) (4.83”/24-HR)(6.16”/24-HR) (8.94”/24-HR) ANALYIS PRE (CFS) POST (CFS) PRE (CFS) POST (CFSPRE (CFS) POST (CFS) PRE (CFS) POST (CFS) POA-1 6.25 0.91 10.07 1.85 13.05 2.63 19.23 4.29 POA-2 7.54 6.89 14.11 13.80 19.68 19.24 31.80 31.06 POA-3 0.03 0.03 0.29 0.26 0.57 0.53 1.29 1.19 POA-4 0.56 0.45 1.10 0.87 1.53 1.22 2.45 1.95 8.0 WATER QUALITY The redevelopment program includes measures to treat runoff from impervious areas prior to discharging offsite. New stormwater controls have been incorporated into the design that result in a reduction in annual stormwater pollutant loads from the site. Through the use of structural and non-structural BMPs, the water quality volume from the watersheds contributing to the proposed drainage system will undergo treatment. Currently, the total project area contains approximately 3.06± acres of impervious (pavement) area or 49% of the site. The redevelopment program increases the impervious area to 3.09± acres of impervious or 50% of the 3 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com East Mill Redevelopment, North Andover MA site, therefore the majority of the of the project area is considered a redevelopment and the balance will be treated as new development. Subcatchments PR-2A includes clean rooftop area, therefore, this watershed will be discharged directly to the subsurface infiltration system. The garage portion of the building totals 0.60 acres of non-rooftop impervious area and will be treated to at least 80% TSS removal (see attached water quality calculation). This watershed area exceeds the 0.03 acres of new impervious area from the project. Subcatchment PR-1A includes a reduction of overall and impervious area as compared to its existing counterpart, therefore, it’s reasonable to assume that the post-development runoff traversing through the existing swale will be treated to at least the same level as the pre-development condition. The following BMPs were selected to treat the average annual TSS load from stormwater runoff under the post-development condition. Deep Sump Hooded Catch Basins Stormwater runoff from proposed pavement areas will be directed via curbing and site grading to catch basins with deep sumps and hooded outlets. The catch basins will trap and remove sediment and larger particles from the stormwater and will improve the performance of subsequent BMP’s. The sumps will be a minimum of 4’ in depth and a regular inspection and cleaning schedule has been proposed to ensure optimal effectiveness. When properly designed and maintained, catch basin sumps are effective in reducing the sediment and pollutant load in runoff. Hydrodynamic Separator Hydrodynamic Separators are designed to remove heavy particles, floating debris and hydrocarbons from stormwater. Stormwater enters the system where floatables and oils are separated prior to the clarified stormwater runoff discharging to an outlet pipe. Since the Hydroworks units are designed to treat the required flow without overflow, bypass, surcharge, or scouring, and since they include a built- in bypass mechanism to accommodate high flow storm events, they are considered "offline" units under the DEP policy as proposed. Subsurface Infiltration Systems (SIS) Subsurface infiltration systems are designed to detain and infiltrate runoff from the site. The system is comprised of RetainIT concrete structures and crushed stone. Proper pretreatment (44% TSS removal min.) is required to in order to achieve 80% TSS. Runoff from the design storm is stored until it exfiltrates through the soil of the basin floor. 9.0GROUNDWATER RECHARGE The DEP Stormwater Management Policy addresses the importance of recharging groundwater and reducing surface runoff. For a redevelopment project, the net increase in site impervious area must be infiltrated to approximate the annual recharge from pre-development conditions. On this site, there is a net increase in impervious area equal to 0.03± acres. The required recharge equals a depth of runoff corresponding to the soil type multiplied by the net increase in impervious area for each soil type in the post development condition. Using a target factor of 0.35 inches for HSG-B, the total required recharge volume is as follows: Rv = (F) x (newly created impervious area) where, Rv =Required recharge volume (cubic feet) F = Target depth factor corresponding to the HSG. 4 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com East Mill Redevelopment, North Andover MA 2 Rv = 0.35-inch x 0.03 acres x (43,560 ft/acre) x (1 ft/12 inch) = 38 cubic feet The available storage within the SIS infiltration basin below the lowest outlet total 2,350± cubic feet, thereby exceeding the required recharge volume. The soil borings indicate that groundwater is at least 10’ below the existing ground surface (EL 91.00±), as such the proposed design accommodates 2’ separation to groundwater for the SIS. Below are the drawdown calculations for the infiltration BMP’s summarizing that each drawdown time will be less than 72 hours as follows: Drawdown calculation = Depth K Where k = 2.41 in/hour Subsurface Infiltration System -1 Drawdown calculation = 36 in = 15 hours < 72 hours = OK 2.41 in/hr 10.0 DRAINAGE CONVEYANCE SYSTEM The proposed stormwater conveyance system was designed to collect and convey runoff from developed areas to the associated stormwater management system BMP’s described in this report. The drainage system consists of one (1) subsurface infiltration system, catch basins, yard drains, manholes and associated piping. 11.0 COMPLIANCE WITH THE MASSACHUSETTS DEP STORMWATER HANDBOOK This study presents a comparative analysis of the pre-development and post-development hydrologic characteristics of the site, and outlines the proposed measures to mitigate flow, provide groundwater recharge, and improve water quality from the site. The best management practices (BMPs) outlined in this report include measures to meet the municipal and the Massachusetts Department of Environmental Protection (DEP) requirements. Below is a summary of how the design complies with each applicable DEP standard. Standard 1: No new stormwater conveyances may discharge untreated directly to or cause erosion in wetlands or waters of the Commonwealth. The proposed stormwater conveyance system does not include any new untreated discharges. The overland connection points will remain consistent with the existing condition. Standard 2: Stormwater management systems shall be designed so that post-development peak discharge rates do not exceed pre-development peak discharge rates. As indicated above and within the supporting HydroCad calculations, the stormwater management system is designed so that post-development peak discharge rates do not exceed pre-development peak discharge rates. Standard 3: Loss of annual recharge to groundwater shall be eliminated or minimized through the use of infiltration measures including 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 5 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com East Mill Redevelopment, North Andover MA infiltrate the required recharge volume as determine in accordance with the Massachusetts Stormwater Handbook. There is a net increase of impervious area and the corresponding required volume of runoff will be recharged to groundwater. Standard 4: Stormwater management systems shall be designed to remove 80% of the average annual post- construction load of Total Suspended Solids (TSS). To aid in removal of total suspended solids, deep sump hooded catch basins and water quality units are proposed. Net increase of onsite non-rooftop impervious areas will be treated beyond 80%. Standard 5: For land uses with higher potential pollutant loads, source control and pollution prevention shall be implemented in accordance with the Massachusetts Stormwater Handbook to eliminate or reduce the discharge of stormwater runoff from such land uses to the maximum extent practicable. 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. Not applicable. Standard 7: A redevelopment project is required to meet the following Stormwater Management Standards only to the maximum extent practicable: Standard 2, Standard 3, and the pretreatment and structural best management practice requirements of Standards 4, 5, and 6. Existing stormwater discharges shall comply with Standard 1 only to the maximum extent practicable. A redevelopment project shall also comply with all other requirements of the Stormwater Management Standards and improve existing conditions. The proposed site complies with the applicable standards to new development and redevelopment. The proposed best management practices improve upon the existing conditions and mitigate for the proposed development impacts. 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, sedimentations, and pollution prevention plan) shall be developed and implemented. The ‘Demolition and Erosion Control Plan’ outlines and depicts measures to control construction related impacts including erosion, sedimentation and other pollutant sources during construction and land disturbance activities. Standard 9: A long-term operation and maintenance plan shall be developed and implemented to ensure that stormwater management systems function as designed. 6 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com East Mill Redevelopment, North Andover MA An Operation and Maintenance Plan (O&M) has been developed for each site that outlines maintenance requirements to ensure longevity of BMP’s. See Appendix A. Standard 10: All illicit discharges to the stormwater management system are prohibited. The proposed stormwater management system does not include any illicit discharges and furthermore the O&M plan includes an illicit discharge statement. 12.0 SUMMARY The stormwater management system for the proposed redevelopment includes measures for collecting, conveying, treating and controlling stormwater runoff from the site. Post-development peak runoff rates have been attenuated for the 2, 10, 25 and 100-year storm events and the collection system has been adequately designed to convey the contributing runoff. The stormwater management system incorporates both structural and non-structural BMP’s to adequately treat and recharge runoff from the proposed redevelopment area and is designed in accordance with the DEP Stormwater Management Policy to the maximum extent practicable. Comprehensive computations and calculations with supporting figures and plans are attached. 7 p: 978-794-5400 f: 978.965.3935 www.cdgengineering.com FIGURE-1 USGS PLAN ESIGN D ROUP, LLC www.cdgengineering.com 4 HIGH STREET SUITE 155 NORTH ANDOVER, MA 01845 IVIL p: 978-794-5400 f: 978-965-3971 G SITE C FIG-3 WATERSHEDS PRE-DEVELOPMENT CN =56 EX-3 AREA = 0.38 AC. CN =94 EX-1 AREA = 2.69 AC. ESIGN D ROUP, LLC www.cdgengineering.com p: 978-794-5400 f: 978-965-3971 IVIL G C EX-2 CN = 66 AREA = 2.68 AC. WATERSHED NOTES: FIG-4 2 8 = WATERSHEDS N PR-4 C POST-DEVELOPMENT 2 - R P CN = 66 AREA = 2.47 AC. PR-3 CN = 56 AREA = 0.35 AC. CN = 98 ESIGN D ROUP, LLC www.cdgengineering.com PR-1 CN = 80 p: 978-794-5400 f: 978-965-3971 IVIL G C CN = 98 PR-2A AREA = 0.24 AC. CN = 76 PR-2B AREA = 0.20 AC. 6 6 = N PR-2 C WATERSHED NOTES: : Other Topsoil <5 Slope (%) Longitude boulders, etc.) Depth Standing Water in Hole - - Soil Latitude (Moist) LOOSE Consistence - - 0 deg. F Soil Structure GRANUALR 7 , - - 0 Sunny Weather Stones Cobbles & None Surface Stones (e.g., cobbles, stones, % by Volume - - 10 Coarse Fragments Gravel Depth Weeping from Pit - - - 09:30 Time Percent Soil Log If yes: - - - Color Grass Vegetation 25 - 29 Redoximorphic Features - - - - ) 08 Date Depth - - - No 10YR 5/6 A Moist (Munsell) Soil Matrix: Color Civil Design Group, LLC ( - - S Yes (USDA Soil Texture , P.E. 1 - T Hole # woodland, agricultural field, vacant lot, etc.) r Commercial/Residential(e.g., C HTM /Laye Topsoil Philip Henry Soil Horizon Prescott Street, North Andover, M 34 118 - Additional Notes: - 0-12 12 34 Depth (in) TEST PIT LOG Site: Logged By: Test Pit Number: Land UseGroundwater Observed: : Other Topsoil <5 Slope (%) Longitude Depth Standing Water in Hole - - istence Soil Latitude (Moist) LOOSE Cons LAR - - Soil Structure GRANU 70 deg. F - - 0 Sunny,Weather Stones Cobbles & None Surface Stones (e.g., cobbles, stones, boulders, etc.) % by Volume - - 10 Coarse Fragments Gravel Depth Weeping from Pit - - - 09:30 Time Percent Soil Log If yes: - - - Color ass Gr Vegetation 25 - 29 Redoximorphic Features - - - - 08 Date Depth - - - No 10YR 5/6 Moist (Munsell) Soil Matrix: Color - - S Yes (USDA P.E. (Civil Design Group, LLC) Soil Texture 2 - T Hole # woodland, agricultural field, vacant lot, etc.) M Commercial/Residential(e.g., C HT /Layer Topsoil Soil Horizon 20 Prescott Street, North Andover, MA Use 48 Additional Notes: -1 0-9 9- 48 Depth (in) TEST PIT LOG Site: Logged By: Philip Henry, Test Pit Number: Land Groundwater Observed: : Other Topsoil <5 Slope (%) Longitude Depth Standing Water in Hole - - Soil Latitude (Moist) LOOSELOOSE Consistence - - Soil Structure GRANUALRGRANULAR 70 deg. F - - 0 0 ce Stones (e.g., cobbles, stones, boulders, etc.) Sunny,Weather Stones Cobbles & None Surfa % by Volume - - 1010 Coarse Fragments Gravel Depth Weeping from Pit Log - - - - 09:30 Time Percent Soil If yes: - - - - Color Grass Vegetation 25 - 29 Redoximorphic Features - - - - - 08 Date Depth - - - No 10YR 5/610YR 5/2 Moist (Munsell) Soil Matrix: Color - - S SL Yes (USDA Soil Texture 4 - T Hole # woodland, agricultural field, vacant lot, etc.) Commercial/Residential(e.g., C2 C1 HTM /Layer Topsoil Soil Horizon Prescott Street, North Andover, MA 90 120 66 - Additional Notes: - 0-9 9- 66 90 Depth (in) TEST PIT LOG Site: Logged By: Philip Henry, P.E. (Civil Design Group, LLC)Test Pit Number: Land UseGroundwater Observed: EX-1 EX-2EX-4 EX-3 POA-4 POA-1 POA-3 POA-2 Routing Diagram for Pre Development Reach SubcatPond Link Prepared by {enter your company name here}, Printed 9/29/2025 HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) AreaCNDescription (acres)(subcatchment-numbers) 1.85261>75% Grass cover, Good, HSG B (EX-1, EX-2, EX-3, EX-4) 1.03798Paved parking, HSG B (EX-1, EX-2, EX-4) 2.02098Roofs, HSG B (EX-1) 1.22255Woods, Good, HSG B (EX-2, EX-3, EX-4) 6.13178TOTAL AREA Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) AreaSoilSubcatchment (acres)GroupNumbers 0.000HSG A 6.131HSG BEX-1, EX-2, EX-3, EX-4 0.000HSG C 0.000HSG D 0.000Other 6.131TOTAL AREA Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 4 Ground Covers (all nodes) HSG-AHSG-BHSG-CHSG-DOtherTotalGroundSubcatchment (acres)(acres)(acres)(acres)(acres)(acres)CoverNumbers 0.0001.8520.0000.0000.0001.852>75% Grass cover, GoodEX-1, EX-2, EX-3, EX-4 0.0001.0370.0000.0000.0001.037Paved parkingEX-1, EX-2, EX-4 0.0002.0200.0000.0000.0002.020RoofsEX-1 0.0001.2220.0000.0000.0001.222Woods, GoodEX-2, EX-3, EX-4 0.0006.1310.0000.0000.0006.131TOTAL AREA NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 5 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=117,014 sf 87.87% Impervious Runoff Depth>2.49" Subcatchment EX-1: Tc=6.0 min CN=94 Runoff=6.25 cfs 0.558 af Runoff Area=116,915 sf 16.84% Impervious Runoff Depth>0.62" Subcatchment EX-2: Tc=6.0 min CN=66 Runoff=1.31 cfs 0.138 af Runoff Area=16,383 sf 0.00% Impervious Runoff Depth>0.26" Subcatchment EX-3: Tc=6.0 min CN=56 Runoff=0.03 cfs 0.008 af Runoff Area=16,751 sf 63.45% Impervious Runoff Depth>1.50" Subcatchment EX-4: Tc=6.0 min CN=82 Runoff=0.56 cfs 0.048 af Inflow=6.25 cfs 0.558 af Link POA-1: Primary=6.25 cfs 0.558 af Inflow=7.54 cfs 0.696 af Link POA-2: Primary=7.54 cfs 0.696 af Inflow=0.03 cfs 0.008 af Link POA-3: Primary=0.03 cfs 0.008 af Inflow=0.56 cfs 0.048 af Link POA-4: Primary=0.56 cfs 0.048 af Total Runoff Area = 6.131 ac Runoff Volume = 0.752 af Average Runoff Depth = 1.47" 50.15% Pervious = 3.074 ac 49.85% Impervious = 3.056 ac NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment EX-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=6.25 cfs @ 12.11 hrs, Volume=0.558 af, Depth>2.49" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 87,98698Roofs, HSG B 14,83498Paved parking, HSG B 14,19461>75% Grass cover, Good, HSG B 117,01494Weighted Average 14,19412.13% Pervious Area 102,82087.87% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-1: Hydrograph Runoff 6.25 cfs NRCC 24-hr D 6 2-Year Rainfall=3.15" 5 Runoff Area=117,014 sf Runoff Volume=0.558 af 4 Runoff Depth>2.49" Tc=6.0 min Flow (cfs) 3 CN=94 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment EX-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.31 cfs @ 12.14 hrs, Volume=0.138 af, Depth>0.62" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 19,69098Paved parking, HSG B 64,13761>75% Grass cover, Good, HSG B 33,08855Woods, Good, HSG B 116,91566Weighted Average 97,22583.16% Pervious Area 19,69016.84% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-2: Hydrograph Runoff 1.31 cfs NRCC 24-hr D 2-Year Rainfall=3.15" Runoff Area=116,915 sf 1 Runoff Volume=0.138 af Runoff Depth>0.62" Tc=6.0 min Flow (cfs) CN=66 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment EX-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.03 cfs @ 12.23 hrs, Volume=0.008 af, Depth>0.26" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 14,58355Woods, Good, HSG B 1,80061>75% Grass cover, Good, HSG B 16,38356Weighted Average 16,383100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-3: Hydrograph Runoff 0.036 0.03 cfs 0.034 0.032 NRCC 24-hr D 0.03 2-Year Rainfall=3.15" 0.028 0.026 Runoff Area=16,383 sf 0.024 Runoff Volume=0.008 af 0.022 0.02 Runoff Depth>0.26" 0.018 Tc=6.0 min 0.016 Flow (cfs) 0.014 CN=56 0.012 0.01 0.008 0.006 0.004 0.002 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment EX-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.56 cfs @ 12.12 hrs, Volume=0.048 af, Depth>1.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 10,62898Paved parking, HSG B 56161>75% Grass cover, Good, HSG B 5,56255Woods, Good, HSG B 16,75182Weighted Average 6,12336.55% Pervious Area 10,62863.45% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-4: Hydrograph Runoff 0.6 0.56 cfs 0.55 NRCC 24-hr D 0.5 2-Year Rainfall=3.15" 0.45 Runoff Area=16,751 sf 0.4 Runoff Volume=0.048 af 0.35 Runoff Depth>1.50" 0.3 Tc=6.0 min Flow (cfs) 0.25 CN=82 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 10 Summary for Link POA-1: Inflow Area =2.686 ac,87.87% Impervious, Inflow Depth > 2.49" for 2-Year event Inflow=6.25 cfs @ 12.11 hrs, Volume=0.558 af Primary=6.25 cfs @ 12.11 hrs, Volume=0.558 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 6.25 cfs 6.25 cfs Inflow Area=2.686 ac 6 5 4 Flow (cfs) 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 11 Summary for Link POA-2: Inflow Area =5.370 ac,52.37% Impervious, Inflow Depth > 1.56" for 2-Year event Inflow=7.54 cfs @ 12.12 hrs, Volume=0.696 af Primary=7.54 cfs @ 12.12 hrs, Volume=0.696 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow Primary 7.54 cfs 8 7.54 cfs Inflow Area=5.370 ac 7 6 5 4 Flow (cfs) 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 12 Summary for Link POA-3: Inflow Area =0.376 ac,0.00% Impervious, Inflow Depth > 0.26" for 2-Year event Inflow=0.03 cfs @ 12.23 hrs, Volume=0.008 af Primary=0.03 cfs @ 12.23 hrs, Volume=0.008 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow Primary 0.03 cfs 0.036 0.03 cfs 0.034 Inflow Area=0.376 ac 0.032 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 Flow (cfs) 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 13 Summary for Link POA-4: Inflow Area =0.385 ac,63.45% Impervious, Inflow Depth > 1.50" for 2-Year event Inflow=0.56 cfs @ 12.12 hrs, Volume=0.048 af Primary=0.56 cfs @ 12.12 hrs, Volume=0.048 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow Primary 0.56 cfs 0.6 0.56 cfs Inflow Area=0.385 ac 0.55 0.5 0.45 0.4 0.35 0.3 Flow (cfs) 0.25 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 14 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=117,014 sf 87.87% Impervious Runoff Depth>4.14" Subcatchment EX-1: Tc=6.0 min CN=94 Runoff=10.07 cfs 0.926 af Runoff Area=116,915 sf 16.84% Impervious Runoff Depth>1.61" Subcatchment EX-2: Tc=6.0 min CN=66 Runoff=4.06 cfs 0.360 af Runoff Area=16,383 sf 0.00% Impervious Runoff Depth>0.95" Subcatchment EX-3: Tc=6.0 min CN=56 Runoff=0.29 cfs 0.030 af Runoff Area=16,751 sf 63.45% Impervious Runoff Depth>2.92" Subcatchment EX-4: Tc=6.0 min CN=82 Runoff=1.10 cfs 0.094 af Inflow=10.07 cfs 0.926 af Link POA-1: Primary=10.07 cfs 0.926 af Inflow=14.11 cfs 1.286 af Link POA-2: Primary=14.11 cfs 1.286 af Inflow=0.29 cfs 0.030 af Link POA-3: Primary=0.29 cfs 0.030 af Inflow=1.10 cfs 0.094 af Link POA-4: Primary=1.10 cfs 0.094 af Total Runoff Area = 6.131 ac Runoff Volume = 1.410 af Average Runoff Depth = 2.76" 50.15% Pervious = 3.074 ac 49.85% Impervious = 3.056 ac NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 15 Summary for Subcatchment EX-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=10.07 cfs @ 12.11 hrs, Volume=0.926 af, Depth>4.14" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 87,98698Roofs, HSG B 14,83498Paved parking, HSG B 14,19461>75% Grass cover, Good, HSG B 117,01494Weighted Average 14,19412.13% Pervious Area 102,82087.87% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-1: Hydrograph Runoff 11 10.07 cfs 10 NRCC 24-hr D 9 10-Year Rainfall=4.83" 8 Runoff Area=117,014 sf 7 Runoff Volume=0.926 af 6 Runoff Depth>4.14" 5 Tc=6.0 min Flow (cfs) CN=94 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 16 Summary for Subcatchment EX-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=4.06 cfs @ 12.12 hrs, Volume=0.360 af, Depth>1.61" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 19,69098Paved parking, HSG B 64,13761>75% Grass cover, Good, HSG B 33,08855Woods, Good, HSG B 116,91566Weighted Average 97,22583.16% Pervious Area 19,69016.84% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-2: Hydrograph Runoff 4.06 cfs 4 NRCC 24-hr D 10-Year Rainfall=4.83" Runoff Area=116,915 sf 3 Runoff Volume=0.360 af Runoff Depth>1.61" Tc=6.0 min 2 Flow (cfs) CN=66 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 17 Summary for Subcatchment EX-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.29 cfs @ 12.14 hrs, Volume=0.030 af, Depth>0.95" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 14,58355Woods, Good, HSG B 1,80061>75% Grass cover, Good, HSG B 16,38356Weighted Average 16,383100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-3: Hydrograph Runoff 0.3 0.29 cfs 0.28 NRCC 24-hr D 0.26 10-Year Rainfall=4.83" 0.24 Runoff Area=16,383 sf 0.22 0.2 Runoff Volume=0.030 af 0.18 Runoff Depth>0.95" 0.16 Tc=6.0 min 0.14 Flow (cfs) 0.12 CN=56 0.1 0.08 0.06 0.04 0.02 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 18 Summary for Subcatchment EX-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.10 cfs @ 12.11 hrs, Volume=0.094 af, Depth>2.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 10,62898Paved parking, HSG B 56161>75% Grass cover, Good, HSG B 5,56255Woods, Good, HSG B 16,75182Weighted Average 6,12336.55% Pervious Area 10,62863.45% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-4: Hydrograph Runoff 1.10 cfs NRCC 24-hr D 1 10-Year Rainfall=4.83" Runoff Area=16,751 sf Runoff Volume=0.094 af Runoff Depth>2.92" Tc=6.0 min Flow (cfs) CN=82 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 19 Summary for Link POA-1: Inflow Area =2.686 ac,87.87% Impervious, Inflow Depth > 4.14" for 10-Year event Inflow=10.07 cfs @ 12.11 hrs, Volume=0.926 af Primary=10.07 cfs @ 12.11 hrs, Volume=0.926 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 10.07 cfs 11 10.07 cfs Inflow Area=2.686 ac 10 9 8 7 6 5 Flow (cfs) 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 20 Summary for Link POA-2: Inflow Area =5.370 ac,52.37% Impervious, Inflow Depth > 2.87" for 10-Year event Inflow=14.11 cfs @ 12.11 hrs, Volume=1.286 af Primary=14.11 cfs @ 12.11 hrs, Volume=1.286 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow Primary 14.11 cfs 15 14.11 cfs Inflow Area=5.370 ac 14 13 12 11 10 9 8 7 Flow (cfs) 6 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 21 Summary for Link POA-3: Inflow Area =0.376 ac,0.00% Impervious, Inflow Depth > 0.95" for 10-Year event Inflow=0.29 cfs @ 12.14 hrs, Volume=0.030 af Primary=0.29 cfs @ 12.14 hrs, Volume=0.030 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow Primary 0.29 cfs 0.29 cfs 0.3 Inflow Area=0.376 ac 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 Flow (cfs) 0.12 0.1 0.08 0.06 0.04 0.02 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 22 Summary for Link POA-4: Inflow Area =0.385 ac,63.45% Impervious, Inflow Depth > 2.92" for 10-Year event Inflow=1.10 cfs @ 12.11 hrs, Volume=0.094 af Primary=1.10 cfs @ 12.11 hrs, Volume=0.094 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow Primary 1.10 cfs 1.10 cfs Inflow Area=0.385 ac 1 Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 23 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=117,014 sf 87.87% Impervious Runoff Depth>5.45" Subcatchment EX-1: Tc=6.0 min CN=94 Runoff=13.05 cfs 1.220 af Runoff Area=116,915 sf 16.84% Impervious Runoff Depth>2.56" Subcatchment EX-2: Tc=6.0 min CN=66 Runoff=6.64 cfs 0.572 af Runoff Area=16,383 sf 0.00% Impervious Runoff Depth>1.69" Subcatchment EX-3: Tc=6.0 min CN=56 Runoff=0.57 cfs 0.053 af Runoff Area=16,751 sf 63.45% Impervious Runoff Depth>4.13" Subcatchment EX-4: Tc=6.0 min CN=82 Runoff=1.53 cfs 0.132 af Inflow=13.05 cfs 1.220 af Link POA-1: Primary=13.05 cfs 1.220 af Inflow=19.68 cfs 1.792 af Link POA-2: Primary=19.68 cfs 1.792 af Inflow=0.57 cfs 0.053 af Link POA-3: Primary=0.57 cfs 0.053 af Inflow=1.53 cfs 0.132 af Link POA-4: Primary=1.53 cfs 0.132 af Total Runoff Area = 6.131 ac Runoff Volume = 1.977 af Average Runoff Depth = 3.87" 50.15% Pervious = 3.074 ac 49.85% Impervious = 3.056 ac NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 24 Summary for Subcatchment EX-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=13.05 cfs @ 12.11 hrs, Volume=1.220 af, Depth>5.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 87,98698Roofs, HSG B 14,83498Paved parking, HSG B 14,19461>75% Grass cover, Good, HSG B 117,01494Weighted Average 14,19412.13% Pervious Area 102,82087.87% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-1: Hydrograph Runoff 14 13.05 cfs 13 NRCC 24-hr D 12 25-Year Rainfall=6.16" 11 Runoff Area=117,014 sf 10 9 Runoff Volume=1.220 af 8 Runoff Depth>5.45" 7 Tc=6.0 min Flow (cfs) 6 CN=94 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 25 Summary for Subcatchment EX-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=6.64 cfs @ 12.12 hrs, Volume=0.572 af, Depth>2.56" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 19,69098Paved parking, HSG B 64,13761>75% Grass cover, Good, HSG B 33,08855Woods, Good, HSG B 116,91566Weighted Average 97,22583.16% Pervious Area 19,69016.84% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-2: Hydrograph Runoff 7 6.64 cfs NRCC 24-hr D 6 25-Year Rainfall=6.16" Runoff Area=116,915 sf 5 Runoff Volume=0.572 af 4 Runoff Depth>2.56" Tc=6.0 min Flow (cfs) 3 CN=66 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 26 Summary for Subcatchment EX-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.57 cfs @ 12.13 hrs, Volume=0.053 af, Depth>1.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 14,58355Woods, Good, HSG B 1,80061>75% Grass cover, Good, HSG B 16,38356Weighted Average 16,383100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-3: Hydrograph Runoff 0.6 0.57 cfs NRCC 24-hr D 0.55 25-Year Rainfall=6.16" 0.5 0.45 Runoff Area=16,383 sf 0.4 Runoff Volume=0.053 af 0.35 Runoff Depth>1.69" 0.3 Tc=6.0 min Flow (cfs) 0.25 CN=56 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 27 Summary for Subcatchment EX-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.53 cfs @ 12.11 hrs, Volume=0.132 af, Depth>4.13" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 10,62898Paved parking, HSG B 56161>75% Grass cover, Good, HSG B 5,56255Woods, Good, HSG B 16,75182Weighted Average 6,12336.55% Pervious Area 10,62863.45% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-4: Hydrograph Runoff 1.53 cfs NRCC 24-hr D 25-Year Rainfall=6.16" Runoff Area=16,751 sf Runoff Volume=0.132 af 1 Runoff Depth>4.13" Tc=6.0 min Flow (cfs) CN=82 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 28 Summary for Link POA-1: Inflow Area =2.686 ac,87.87% Impervious, Inflow Depth > 5.45" for 25-Year event Inflow=13.05 cfs @ 12.11 hrs, Volume=1.220 af Primary=13.05 cfs @ 12.11 hrs, Volume=1.220 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 13.05 cfs 14 13.05 cfs Inflow Area=2.686 ac 13 12 11 10 9 8 7 Flow (cfs) 6 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 29 Summary for Link POA-2: Inflow Area =5.370 ac,52.37% Impervious, Inflow Depth > 4.00" for 25-Year event Inflow=19.68 cfs @ 12.11 hrs, Volume=1.792 af Primary=19.68 cfs @ 12.11 hrs, Volume=1.792 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow 22 Primary 19.68 cfs 21 19.68 cfs 20 Inflow Area=5.370 ac 19 18 17 16 15 14 13 12 11 10 Flow (cfs) 9 8 7 6 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 30 Summary for Link POA-3: Inflow Area =0.376 ac,0.00% Impervious, Inflow Depth > 1.69" for 25-Year event Inflow=0.57 cfs @ 12.13 hrs, Volume=0.053 af Primary=0.57 cfs @ 12.13 hrs, Volume=0.053 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow Primary 0.57 cfs 0.57 cfs 0.6 Inflow Area=0.376 ac 0.55 0.5 0.45 0.4 0.35 0.3 Flow (cfs) 0.25 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 31 Summary for Link POA-4: Inflow Area =0.385 ac,63.45% Impervious, Inflow Depth > 4.13" for 25-Year event Inflow=1.53 cfs @ 12.11 hrs, Volume=0.132 af Primary=1.53 cfs @ 12.11 hrs, Volume=0.132 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow Primary 1.53 cfs 1.53 cfs Inflow Area=0.385 ac 1 Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 32 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=117,014 sf 87.87% Impervious Runoff Depth>8.21" Subcatchment EX-1: Tc=6.0 min CN=94 Runoff=19.23 cfs 1.838 af Runoff Area=116,915 sf 16.84% Impervious Runoff Depth>4.79" Subcatchment EX-2: Tc=6.0 min CN=66 Runoff=12.58 cfs 1.070 af Runoff Area=16,383 sf 0.00% Impervious Runoff Depth>3.56" Subcatchment EX-3: Tc=6.0 min CN=56 Runoff=1.29 cfs 0.112 af Runoff Area=16,751 sf 63.45% Impervious Runoff Depth>6.75" Subcatchment EX-4: Tc=6.0 min CN=82 Runoff=2.45 cfs 0.216 af Inflow=19.23 cfs 1.838 af Link POA-1: Primary=19.23 cfs 1.838 af Inflow=31.80 cfs 2.908 af Link POA-2: Primary=31.80 cfs 2.908 af Inflow=1.29 cfs 0.112 af Link POA-3: Primary=1.29 cfs 0.112 af Inflow=2.45 cfs 0.216 af Link POA-4: Primary=2.45 cfs 0.216 af Total Runoff Area = 6.131 ac Runoff Volume = 3.236 af Average Runoff Depth = 6.33" 50.15% Pervious = 3.074 ac 49.85% Impervious = 3.056 ac NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 33 Summary for Subcatchment EX-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=19.23 cfs @ 12.11 hrs, Volume=1.838 af, Depth>8.21" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 87,98698Roofs, HSG B 14,83498Paved parking, HSG B 14,19461>75% Grass cover, Good, HSG B 117,01494Weighted Average 14,19412.13% Pervious Area 102,82087.87% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-1: Hydrograph Runoff 21 19.23 cfs 20 19 NRCC 24-hr D 18 17 100-Year Rainfall=8.94" 16 Runoff Area=117,014 sf 15 14 Runoff Volume=1.838 af 13 12 Runoff Depth>8.21" 11 10 Tc=6.0 min Flow (cfs) 9 8 CN=94 7 6 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 34 Summary for Subcatchment EX-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=12.58 cfs @ 12.12 hrs, Volume=1.070 af, Depth>4.79" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 19,69098Paved parking, HSG B 64,13761>75% Grass cover, Good, HSG B 33,08855Woods, Good, HSG B 116,91566Weighted Average 97,22583.16% Pervious Area 19,69016.84% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-2: Hydrograph 14 Runoff 12.58 cfs 13 NRCC 24-hr D 12 100-Year Rainfall=8.94" 11 10 Runoff Area=116,915 sf 9 Runoff Volume=1.070 af 8 Runoff Depth>4.79" 7 Tc=6.0 min Flow (cfs) 6 CN=66 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 35 Summary for Subcatchment EX-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.29 cfs @ 12.12 hrs, Volume=0.112 af, Depth>3.56" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 14,58355Woods, Good, HSG B 1,80061>75% Grass cover, Good, HSG B 16,38356Weighted Average 16,383100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-3: Hydrograph Runoff 1.29 cfs NRCC 24-hr D 100-Year Rainfall=8.94" Runoff Area=16,383 sf 1 Runoff Volume=0.112 af Runoff Depth>3.56" Tc=6.0 min Flow (cfs) CN=56 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 36 Summary for Subcatchment EX-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=2.45 cfs @ 12.11 hrs, Volume=0.216 af, Depth>6.75" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 10,62898Paved parking, HSG B 56161>75% Grass cover, Good, HSG B 5,56255Woods, Good, HSG B 16,75182Weighted Average 6,12336.55% Pervious Area 10,62863.45% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment EX-4: Hydrograph Runoff 2.45 cfs NRCC 24-hr D 100-Year Rainfall=8.94" 2 Runoff Area=16,751 sf Runoff Volume=0.216 af Runoff Depth>6.75" Tc=6.0 min Flow (cfs) 1 CN=82 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 37 Summary for Link POA-1: Inflow Area =2.686 ac,87.87% Impervious, Inflow Depth > 8.21" for 100-Year event Inflow=19.23 cfs @ 12.11 hrs, Volume=1.838 af Primary=19.23 cfs @ 12.11 hrs, Volume=1.838 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 19.23 cfs 21 19.23 cfs 20 Inflow Area=2.686 ac 19 18 17 16 15 14 13 12 11 10 Flow (cfs) 9 8 7 6 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 38 Summary for Link POA-2: Inflow Area =5.370 ac,52.37% Impervious, Inflow Depth > 6.50" for 100-Year event Inflow=31.80 cfs @ 12.11 hrs, Volume=2.908 af Primary=31.80 cfs @ 12.11 hrs, Volume=2.908 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow Primary 31.80 cfs 34 31.80 cfs Inflow Area=5.370 ac 32 30 28 26 24 22 20 18 16 Flow (cfs) 14 12 10 8 6 4 2 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 39 Summary for Link POA-3: Inflow Area =0.376 ac,0.00% Impervious, Inflow Depth > 3.56" for 100-Year event Inflow=1.29 cfs @ 12.12 hrs, Volume=0.112 af Primary=1.29 cfs @ 12.12 hrs, Volume=0.112 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow Primary 1.29 cfs 1.29 cfs Inflow Area=0.376 ac 1 Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Pre Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 40 Summary for Link POA-4: Inflow Area =0.385 ac,63.45% Impervious, Inflow Depth > 6.75" for 100-Year event Inflow=2.45 cfs @ 12.11 hrs, Volume=0.216 af Primary=2.45 cfs @ 12.11 hrs, Volume=0.216 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow Primary 2.45 cfs 2.45 cfs Inflow Area=0.385 ac 2 Flow (cfs) 1 0 0123456789101112131415161718192021222324 Time (hours) PR-4 PR-3 PR-1 PR-2 POA-1 POA-2 POA-4 POA-3 PR-2A PR-2C SIS-1 PR-2B Routing Diagram for Post Development Reach SubcatPond Link Prepared by {enter your company name here}, Printed 9/29/2025 HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) AreaCNDescription (acres)(subcatchment-numbers) 2.33361>75% Grass cover, Good, HSG B (PR-1, PR-2, PR-2B, PR-3, PR-4) 0.98298Paved parking, HSG B (PR-1, PR-2, PR-2B, PR-4) 2.11498Roofs, HSG B (PR-2A, PR-2C) 0.70155Woods, Good, HSG B (PR-2, PR-3) 6.13179TOTAL AREA Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) AreaSoilSubcatchment (acres)GroupNumbers 0.000HSG A 6.131HSG BPR-1, PR-2, PR-2A, PR-2B, PR-2C, PR-3, PR-4 0.000HSG C 0.000HSG D 0.000Other 6.131TOTAL AREA Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 4 Ground Covers (all nodes) HSG-AHSG-BHSG-CHSG-DOtherTotalGroundSubcatchment (acres)(acres)(acres)(acres)(acres)(acres)CoverNumbers 0.0002.3330.0000.0000.0002.333>75% Grass cover, GoodPR-1, PR-2, PR-2B, PR-3, PR-4 0.0000.9820.0000.0000.0000.982Paved parkingPR-1, PR-2, PR-2B, PR-4 0.0002.1140.0000.0000.0002.114RoofsPR-2A, PR-2C 0.0000.7010.0000.0000.0000.701Woods, GoodPR-2, PR-3 0.0006.1310.0000.0000.0006.131TOTAL AREA NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 5 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=30,101 sf 50.47% Impervious Runoff Depth>1.36" Subcatchment PR-1: Tc=6.0 min CN=80 Runoff=0.91 cfs 0.078 af Runoff Area=107,780 sf 15.38% Impervious Runoff Depth>0.62" Subcatchment PR-2: Tc=6.0 min CN=66 Runoff=1.21 cfs 0.127 af Runoff Area=10,400 sf 100.00% Impervious Runoff Depth>2.92" Subcatchment PR-2A: Tc=6.0 min CN=98 Runoff=0.60 cfs 0.058 af Runoff Area=8,606 sf 41.33% Impervious Runoff Depth>1.12" Subcatchment PR-2B: Tc=6.0 min CN=76 Runoff=0.21 cfs 0.018 af Runoff Area=81,703 sf 100.00% Impervious Runoff Depth>2.92" Subcatchment PR-2C: Tc=6.0 min CN=98 Runoff=4.74 cfs 0.456 af Runoff Area=15,135 sf 0.00% Impervious Runoff Depth>0.26" Subcatchment PR-3: Tc=6.0 min CN=56 Runoff=0.03 cfs 0.008 af Runoff Area=13,332 sf 56.00% Impervious Runoff Depth>1.50" Subcatchment PR-4: Tc=6.0 min CN=82 Runoff=0.45 cfs 0.038 af Peak Elev=95.98' Storage=767 cf Inflow=0.81 cfs 0.076 af Pond SIS-1: Discarded=0.04 cfs 0.059 af Primary=0.42 cfs 0.018 af Outflow=0.46 cfs 0.076 af Inflow=0.91 cfs 0.078 af Link POA-1: Primary=0.91 cfs 0.078 af Inflow=6.89 cfs 0.679 af Link POA-2: Primary=6.89 cfs 0.679 af Inflow=0.03 cfs 0.008 af Link POA-3: Primary=0.03 cfs 0.008 af Inflow=0.45 cfs 0.038 af Link POA-4: Primary=0.45 cfs 0.038 af Total Runoff Area = 6.131 ac Runoff Volume = 0.784 af Average Runoff Depth = 1.53" 49.49% Pervious = 3.034 ac 50.51% Impervious = 3.097 ac NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment PR-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.91 cfs @ 12.12 hrs, Volume=0.078 af, Depth>1.36" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 15,19398Paved parking, HSG B 14,90861>75% Grass cover, Good, HSG B 30,10180Weighted Average 14,90849.53% Pervious Area 15,19350.47% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-1: Hydrograph Runoff 1 0.91 cfs NRCC 24-hr D 2-Year Rainfall=3.15" Runoff Area=30,101 sf Runoff Volume=0.078 af Runoff Depth>1.36" Tc=6.0 min Flow (cfs) CN=80 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment PR-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.21 cfs @ 12.14 hrs, Volume=0.127 af, Depth>0.62" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 16,57298Paved parking, HSG B 72,73161>75% Grass cover, Good, HSG B 18,47755Woods, Good, HSG B 107,78066Weighted Average 91,20884.62% Pervious Area 16,57215.38% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2: Hydrograph Runoff 1.21 cfs NRCC 24-hr D 2-Year Rainfall=3.15" 1 Runoff Area=107,780 sf Runoff Volume=0.127 af Runoff Depth>0.62" Tc=6.0 min Flow (cfs) CN=66 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment PR-2A: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.60 cfs @ 12.11 hrs, Volume=0.058 af, Depth>2.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 10,40098Roofs, HSG B 10,400100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2A: Hydrograph Runoff 0.65 0.60 cfs 0.6 NRCC 24-hr D 0.55 2-Year Rainfall=3.15" 0.5 Runoff Area=10,400 sf 0.45 Runoff Volume=0.058 af 0.4 Runoff Depth>2.92" 0.35 0.3 Tc=6.0 min Flow (cfs) 0.25 CN=98 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment PR-2B: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.21 cfs @ 12.12 hrs, Volume=0.018 af, Depth>1.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 3,55798Paved parking, HSG B 5,04961>75% Grass cover, Good, HSG B 8,60676Weighted Average 5,04958.67% Pervious Area 3,55741.33% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2B: Hydrograph 0.23 Runoff 0.22 0.21 cfs 0.21 NRCC 24-hr D 0.2 0.19 2-Year Rainfall=3.15" 0.18 0.17 Runoff Area=8,606 sf 0.16 0.15 Runoff Volume=0.018 af 0.14 0.13 Runoff Depth>1.12" 0.12 0.11 Tc=6.0 min Flow (cfs) 0.1 0.09 CN=76 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 10 Summary for Subcatchment PR-2C: \[49\] Hint: Tc<2dt may require smaller dt Runoff=4.74 cfs @ 12.11 hrs, Volume=0.456 af, Depth>2.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 81,70398Roofs, HSG B 81,703100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2C: Hydrograph Runoff 5 4.74 cfs NRCC 24-hr D 2-Year Rainfall=3.15" 4 Runoff Area=81,703 sf Runoff Volume=0.456 af 3 Runoff Depth>2.92" Tc=6.0 min Flow (cfs) 2 CN=98 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 11 Summary for Subcatchment PR-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.03 cfs @ 12.23 hrs, Volume=0.008 af, Depth>0.26" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 3,09361>75% Grass cover, Good, HSG B 12,04255Woods, Good, HSG B 15,13556Weighted Average 15,135100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-3: Hydrograph 0.034 Runoff 0.032 0.03 cfs 0.03 NRCC 24-hr D 0.028 2-Year Rainfall=3.15" 0.026 0.024 Runoff Area=15,135 sf 0.022 Runoff Volume=0.008 af 0.02 0.018 Runoff Depth>0.26" 0.016 Tc=6.0 min Flow (cfs) 0.014 CN=56 0.012 0.01 0.008 0.006 0.004 0.002 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 12 Summary for Subcatchment PR-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.45 cfs @ 12.12 hrs, Volume=0.038 af, Depth>1.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 2-Year Rainfall=3.15" Area (sf)CNDescription 7,46698Paved parking, HSG B 5,86661>75% Grass cover, Good, HSG B 13,33282Weighted Average 5,86644.00% Pervious Area 7,46656.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-4: Hydrograph 0.5 Runoff 0.48 0.45 cfs 0.46 0.44 NRCC 24-hr D 0.42 0.4 2-Year Rainfall=3.15" 0.38 0.36 Runoff Area=13,332 sf 0.34 0.32 Runoff Volume=0.038 af 0.3 0.28 Runoff Depth>1.50" 0.26 0.24 Tc=6.0 min 0.22 Flow (cfs) 0.2 0.18 CN=82 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 13 Summary for Pond SIS-1: \[92\] Warning: Device #2 is above defined storage Inflow Area =0.436 ac,73.43% Impervious, Inflow Depth > 2.10" for 2-Year event Inflow=0.81 cfs @ 12.11 hrs, Volume=0.076 af Outflow=0.46 cfs @ 12.26 hrs, Volume=0.076 af, Atten= 44%, Lag= 8.9 min Discarded=0.04 cfs @ 10.70 hrs, Volume=0.059 af Primary=0.42 cfs @ 12.26 hrs, Volume=0.018 af Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Peak Elev= 95.98' @ 12.26 hrs Surf.Area= 784 sf Storage= 767 cf Plug-Flow detention time= 92.3 min calculated for 0.076 af (100% of inflow) Center-of-Mass det. time= 90.6 min ( 881.4 - 790.9 ) VolumeInvertAvail.StorageStorage Description #195.00'2,352 cf x 16 7.00'W x 7.00'L x 3.00'H Prismatoid DeviceRouting InvertOutlet Devices #1Primary95.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 95.00' / 94.00' S= 0.0100 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #2Device 198.00'4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3Device 195.75' C= 0.600 4.0" Vert. Orifice/Grate X 4.00 #4Discarded95.00' 2.410 in/hr Exfiltration over Surface area Max=0.04 cfs @ 10.70 hrs HW=95.03' (Free Discharge) Discarded OutFlow (Exfiltration Controls 0.04 cfs) 4=Exfiltration Max=0.40 cfs @ 12.26 hrs HW=95.97' (Free Discharge) Primary OutFlow (Passes 0.40 cfs of 2.06 cfs potential flow) 1=Culvert ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Orifice Controls 0.40 cfs @ 1.60 fps) 3=Orifice/Grate NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 14 Pond SIS-1: Hydrograph Inflow 0.81 cfs Outflow Discarded Inflow Area=0.436 ac Primary 0.9 0.85 Peak Elev=95.98' 0.8 0.75 Storage=767 cf 0.7 0.65 0.6 0.46 cfs 0.55 0.5 0.42 cfs 0.45 0.4 Flow (cfs) 0.35 0.3 0.25 0.2 0.15 0.04 cfs 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 15 Summary for Link POA-1: Inflow Area =0.691 ac,50.47% Impervious, Inflow Depth > 1.36" for 2-Year event Inflow=0.91 cfs @ 12.12 hrs, Volume=0.078 af Primary=0.91 cfs @ 12.12 hrs, Volume=0.078 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 0.91 cfs 1 0.91 cfs Inflow Area=0.691 ac Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 16 Summary for Link POA-2: Inflow Area =5.477 ac,53.41% Impervious, Inflow Depth > 1.49" for 2-Year event Inflow=6.89 cfs @ 12.12 hrs, Volume=0.679 af Primary=6.89 cfs @ 12.12 hrs, Volume=0.679 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow Primary 6.89 cfs 6.89 cfs 7 Inflow Area=5.477 ac 6 5 4 Flow (cfs) 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 17 Summary for Link POA-3: Inflow Area =0.347 ac,0.00% Impervious, Inflow Depth > 0.26" for 2-Year event Inflow=0.03 cfs @ 12.23 hrs, Volume=0.008 af Primary=0.03 cfs @ 12.23 hrs, Volume=0.008 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow 0.034 Primary 0.03 cfs 0.03 cfs 0.032 Inflow Area=0.347 ac 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 Flow (cfs) 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 2-Year Rainfall=3.15" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 18 Summary for Link POA-4: Inflow Area =0.306 ac,56.00% Impervious, Inflow Depth > 1.50" for 2-Year event Inflow=0.45 cfs @ 12.12 hrs, Volume=0.038 af Primary=0.45 cfs @ 12.12 hrs, Volume=0.038 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow 0.5 Primary 0.45 cfs 0.48 0.45 cfs 0.46 Inflow Area=0.306 ac 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 Flow (cfs) 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 19 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=30,101 sf 50.47% Impervious Runoff Depth>2.74" Subcatchment PR-1: Tc=6.0 min CN=80 Runoff=1.85 cfs 0.158 af Runoff Area=107,780 sf 15.38% Impervious Runoff Depth>1.61" Subcatchment PR-2: Tc=6.0 min CN=66 Runoff=3.74 cfs 0.332 af Runoff Area=10,400 sf 100.00% Impervious Runoff Depth>4.59" Subcatchment PR-2A: Tc=6.0 min CN=98 Runoff=0.93 cfs 0.091 af Runoff Area=8,606 sf 41.33% Impervious Runoff Depth>2.39" Subcatchment PR-2B: Tc=6.0 min CN=76 Runoff=0.46 cfs 0.039 af Runoff Area=81,703 sf 100.00% Impervious Runoff Depth>4.59" Subcatchment PR-2C: Tc=6.0 min CN=98 Runoff=7.33 cfs 0.717 af Runoff Area=15,135 sf 0.00% Impervious Runoff Depth>0.95" Subcatchment PR-3: Tc=6.0 min CN=56 Runoff=0.26 cfs 0.028 af Runoff Area=13,332 sf 56.00% Impervious Runoff Depth>2.92" Subcatchment PR-4: Tc=6.0 min CN=82 Runoff=0.87 cfs 0.075 af Peak Elev=96.28' Storage=1,003 cf Inflow=1.40 cfs 0.131 af Pond SIS-1: Discarded=0.04 cfs 0.067 af Primary=1.01 cfs 0.055 af Outflow=1.06 cfs 0.122 af Inflow=1.85 cfs 0.158 af Link POA-1: Primary=1.85 cfs 0.158 af Inflow=13.80 cfs 1.263 af Link POA-2: Primary=13.80 cfs 1.263 af Inflow=0.26 cfs 0.028 af Link POA-3: Primary=0.26 cfs 0.028 af Inflow=0.87 cfs 0.075 af Link POA-4: Primary=0.87 cfs 0.075 af Total Runoff Area = 6.131 ac Runoff Volume = 1.440 af Average Runoff Depth = 2.82" 49.49% Pervious = 3.034 ac 50.51% Impervious = 3.097 ac NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 20 Summary for Subcatchment PR-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.85 cfs @ 12.11 hrs, Volume=0.158 af, Depth>2.74" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 15,19398Paved parking, HSG B 14,90861>75% Grass cover, Good, HSG B 30,10180Weighted Average 14,90849.53% Pervious Area 15,19350.47% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-1: Hydrograph Runoff 2 1.85 cfs NRCC 24-hr D 10-Year Rainfall=4.83" Runoff Area=30,101 sf Runoff Volume=0.158 af Runoff Depth>2.74" 1 Tc=6.0 min Flow (cfs) CN=80 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 21 Summary for Subcatchment PR-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=3.74 cfs @ 12.12 hrs, Volume=0.332 af, Depth>1.61" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 16,57298Paved parking, HSG B 72,73161>75% Grass cover, Good, HSG B 18,47755Woods, Good, HSG B 107,78066Weighted Average 91,20884.62% Pervious Area 16,57215.38% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2: Hydrograph Runoff 4 3.74 cfs NRCC 24-hr D 10-Year Rainfall=4.83" 3 Runoff Area=107,780 sf Runoff Volume=0.332 af Runoff Depth>1.61" 2 Tc=6.0 min Flow (cfs) CN=66 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 22 Summary for Subcatchment PR-2A: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.93 cfs @ 12.11 hrs, Volume=0.091 af, Depth>4.59" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 10,40098Roofs, HSG B 10,400100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2A: Hydrograph Runoff 1 0.93 cfs NRCC 24-hr D 10-Year Rainfall=4.83" Runoff Area=10,400 sf Runoff Volume=0.091 af Runoff Depth>4.59" Tc=6.0 min Flow (cfs) CN=98 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 23 Summary for Subcatchment PR-2B: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.46 cfs @ 12.12 hrs, Volume=0.039 af, Depth>2.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 3,55798Paved parking, HSG B 5,04961>75% Grass cover, Good, HSG B 8,60676Weighted Average 5,04958.67% Pervious Area 3,55741.33% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2B: Hydrograph Runoff 0.5 0.46 cfs 0.48 0.46 NRCC 24-hr D 0.44 0.42 10-Year Rainfall=4.83" 0.4 0.38 Runoff Area=8,606 sf 0.36 0.34 0.32 Runoff Volume=0.039 af 0.3 0.28 Runoff Depth>2.39" 0.26 0.24 Tc=6.0 min Flow (cfs) 0.22 0.2 CN=76 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 24 Summary for Subcatchment PR-2C: \[49\] Hint: Tc<2dt may require smaller dt Runoff=7.33 cfs @ 12.11 hrs, Volume=0.717 af, Depth>4.59" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 81,70398Roofs, HSG B 81,703100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2C: Hydrograph Runoff 8 7.33 cfs NRCC 24-hr D 7 10-Year Rainfall=4.83" 6 Runoff Area=81,703 sf Runoff Volume=0.717 af 5 Runoff Depth>4.59" 4 Tc=6.0 min Flow (cfs) 3 CN=98 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 25 Summary for Subcatchment PR-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.26 cfs @ 12.14 hrs, Volume=0.028 af, Depth>0.95" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 3,09361>75% Grass cover, Good, HSG B 12,04255Woods, Good, HSG B 15,13556Weighted Average 15,135100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-3: Hydrograph Runoff 0.28 0.26 cfs 0.26 NRCC 24-hr D 0.24 10-Year Rainfall=4.83" 0.22 Runoff Area=15,135 sf 0.2 Runoff Volume=0.028 af 0.18 0.16 Runoff Depth>0.95" 0.14 Tc=6.0 min Flow (cfs) 0.12 CN=56 0.1 0.08 0.06 0.04 0.02 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 26 Summary for Subcatchment PR-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.87 cfs @ 12.11 hrs, Volume=0.075 af, Depth>2.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 10-Year Rainfall=4.83" Area (sf)CNDescription 7,46698Paved parking, HSG B 5,86661>75% Grass cover, Good, HSG B 13,33282Weighted Average 5,86644.00% Pervious Area 7,46656.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-4: Hydrograph Runoff 0.95 0.87 cfs 0.9 0.85 NRCC 24-hr D 0.8 10-Year Rainfall=4.83" 0.75 0.7 Runoff Area=13,332 sf 0.65 0.6 Runoff Volume=0.075 af 0.55 Runoff Depth>2.92" 0.5 0.45 Tc=6.0 min Flow (cfs) 0.4 0.35 CN=82 0.3 0.25 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 27 Summary for Pond SIS-1: \[92\] Warning: Device #2 is above defined storage Inflow Area =0.436 ac,73.43% Impervious, Inflow Depth > 3.60" for 10-Year event Inflow=1.40 cfs @ 12.11 hrs, Volume=0.131 af Outflow=1.06 cfs @ 12.20 hrs, Volume=0.122 af, Atten= 24%, Lag= 5.4 min Discarded=0.04 cfs @ 9.30 hrs, Volume=0.067 af Primary=1.01 cfs @ 12.20 hrs, Volume=0.055 af Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Peak Elev= 96.28' @ 12.20 hrs Surf.Area= 784 sf Storage= 1,003 cf Plug-Flow detention time= 77.6 min calculated for 0.122 af (93% of inflow) Center-of-Mass det. time= 40.1 min ( 823.3 - 783.2 ) VolumeInvertAvail.StorageStorage Description #195.00'2,352 cf x 16 7.00'W x 7.00'L x 3.00'H Prismatoid DeviceRouting InvertOutlet Devices #1Primary95.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 95.00' / 94.00' S= 0.0100 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #2Device 198.00'4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3Device 195.75' C= 0.600 4.0" Vert. Orifice/Grate X 4.00 #4Discarded95.00' 2.410 in/hr Exfiltration over Surface area Max=0.04 cfs @ 9.30 hrs HW=95.03' (Free Discharge) Discarded OutFlow (Exfiltration Controls 0.04 cfs) 4=Exfiltration Max=1.01 cfs @ 12.20 hrs HW=96.28' (Free Discharge) Primary OutFlow (Passes 1.01 cfs of 2.63 cfs potential flow) 1=Culvert ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Orifice Controls 1.01 cfs @ 2.89 fps) 3=Orifice/Grate NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 28 Pond SIS-1: Hydrograph Inflow 1.40 cfs Outflow Discarded Inflow Area=0.436 ac Primary Peak Elev=96.28' 1.06 cfs Storage=1,003 cf 1.01 cfs 1 Flow (cfs) 0.04 cfs 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 29 Summary for Link POA-1: Inflow Area =0.691 ac,50.47% Impervious, Inflow Depth > 2.74" for 10-Year event Inflow=1.85 cfs @ 12.11 hrs, Volume=0.158 af Primary=1.85 cfs @ 12.11 hrs, Volume=0.158 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 1.85 cfs 2 1.85 cfs Inflow Area=0.691 ac 1 Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 30 Summary for Link POA-2: Inflow Area =5.477 ac,53.41% Impervious, Inflow Depth > 2.77" for 10-Year event Inflow=13.80 cfs @ 12.12 hrs, Volume=1.263 af Primary=13.80 cfs @ 12.12 hrs, Volume=1.263 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow Primary 13.80 cfs 15 13.80 cfs 14 Inflow Area=5.477 ac 13 12 11 10 9 8 7 Flow (cfs) 6 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 31 Summary for Link POA-3: Inflow Area =0.347 ac,0.00% Impervious, Inflow Depth > 0.95" for 10-Year event Inflow=0.26 cfs @ 12.14 hrs, Volume=0.028 af Primary=0.26 cfs @ 12.14 hrs, Volume=0.028 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow Primary 0.26 cfs 0.28 0.26 cfs Inflow Area=0.347 ac 0.26 0.24 0.22 0.2 0.18 0.16 0.14 Flow (cfs) 0.12 0.1 0.08 0.06 0.04 0.02 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 10-Year Rainfall=4.83" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 32 Summary for Link POA-4: Inflow Area =0.306 ac,56.00% Impervious, Inflow Depth > 2.92" for 10-Year event Inflow=0.87 cfs @ 12.11 hrs, Volume=0.075 af Primary=0.87 cfs @ 12.11 hrs, Volume=0.075 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow Primary 0.87 cfs 0.95 0.87 cfs 0.9 Inflow Area=0.306 ac 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 Flow (cfs) 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 33 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=30,101 sf 50.47% Impervious Runoff Depth>3.92" Subcatchment PR-1: Tc=6.0 min CN=80 Runoff=2.63 cfs 0.226 af Runoff Area=107,780 sf 15.38% Impervious Runoff Depth>2.56" Subcatchment PR-2: Tc=6.0 min CN=66 Runoff=6.12 cfs 0.527 af Runoff Area=10,400 sf 100.00% Impervious Runoff Depth>5.92" Subcatchment PR-2A: Tc=6.0 min CN=98 Runoff=1.19 cfs 0.118 af Runoff Area=8,606 sf 41.33% Impervious Runoff Depth>3.52" Subcatchment PR-2B: Tc=6.0 min CN=76 Runoff=0.68 cfs 0.058 af Runoff Area=81,703 sf 100.00% Impervious Runoff Depth>5.92" Subcatchment PR-2C: Tc=6.0 min CN=98 Runoff=9.37 cfs 0.925 af Runoff Area=15,135 sf 0.00% Impervious Runoff Depth>1.69" Subcatchment PR-3: Tc=6.0 min CN=56 Runoff=0.53 cfs 0.049 af Runoff Area=13,332 sf 56.00% Impervious Runoff Depth>4.13" Subcatchment PR-4: Tc=6.0 min CN=82 Runoff=1.22 cfs 0.105 af Peak Elev=96.51' Storage=1,185 cf Inflow=1.87 cfs 0.176 af Pond SIS-1: Discarded=0.04 cfs 0.072 af Primary=1.30 cfs 0.091 af Outflow=1.34 cfs 0.163 af Inflow=2.63 cfs 0.226 af Link POA-1: Primary=2.63 cfs 0.226 af Inflow=19.24 cfs 1.769 af Link POA-2: Primary=19.24 cfs 1.769 af Inflow=0.53 cfs 0.049 af Link POA-3: Primary=0.53 cfs 0.049 af Inflow=1.22 cfs 0.105 af Link POA-4: Primary=1.22 cfs 0.105 af Total Runoff Area = 6.131 ac Runoff Volume = 2.008 af Average Runoff Depth = 3.93" 49.49% Pervious = 3.034 ac 50.51% Impervious = 3.097 ac NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 34 Summary for Subcatchment PR-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=2.63 cfs @ 12.11 hrs, Volume=0.226 af, Depth>3.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 15,19398Paved parking, HSG B 14,90861>75% Grass cover, Good, HSG B 30,10180Weighted Average 14,90849.53% Pervious Area 15,19350.47% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-1: Hydrograph Runoff 2.63 cfs NRCC 24-hr D 25-Year Rainfall=6.16" Runoff Area=30,101 sf 2 Runoff Volume=0.226 af Runoff Depth>3.92" Tc=6.0 min Flow (cfs) CN=80 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 35 Summary for Subcatchment PR-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=6.12 cfs @ 12.12 hrs, Volume=0.527 af, Depth>2.56" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 16,57298Paved parking, HSG B 72,73161>75% Grass cover, Good, HSG B 18,47755Woods, Good, HSG B 107,78066Weighted Average 91,20884.62% Pervious Area 16,57215.38% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2: Hydrograph Runoff 6.12 cfs 6 NRCC 24-hr D 25-Year Rainfall=6.16" 5 Runoff Area=107,780 sf Runoff Volume=0.527 af 4 Runoff Depth>2.56" Tc=6.0 min 3 Flow (cfs) CN=66 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 36 Summary for Subcatchment PR-2A: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.19 cfs @ 12.11 hrs, Volume=0.118 af, Depth>5.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 10,40098Roofs, HSG B 10,400100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2A: Hydrograph Runoff 1.19 cfs NRCC 24-hr D 25-Year Rainfall=6.16" 1 Runoff Area=10,400 sf Runoff Volume=0.118 af Runoff Depth>5.92" Tc=6.0 min Flow (cfs) CN=98 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 37 Summary for Subcatchment PR-2B: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.68 cfs @ 12.11 hrs, Volume=0.058 af, Depth>3.52" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 3,55798Paved parking, HSG B 5,04961>75% Grass cover, Good, HSG B 8,60676Weighted Average 5,04958.67% Pervious Area 3,55741.33% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2B: Hydrograph 0.75 Runoff 0.68 cfs 0.7 NRCC 24-hr D 0.65 0.6 25-Year Rainfall=6.16" 0.55 Runoff Area=8,606 sf 0.5 Runoff Volume=0.058 af 0.45 Runoff Depth>3.52" 0.4 0.35 Tc=6.0 min Flow (cfs) 0.3 CN=76 0.25 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 38 Summary for Subcatchment PR-2C: \[49\] Hint: Tc<2dt may require smaller dt Runoff=9.37 cfs @ 12.11 hrs, Volume=0.925 af, Depth>5.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 81,70398Roofs, HSG B 81,703100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2C: Hydrograph Runoff 10 9.37 cfs NRCC 24-hr D 9 25-Year Rainfall=6.16" 8 Runoff Area=81,703 sf 7 Runoff Volume=0.925 af 6 Runoff Depth>5.92" 5 Tc=6.0 min Flow (cfs) 4 CN=98 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 39 Summary for Subcatchment PR-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=0.53 cfs @ 12.13 hrs, Volume=0.049 af, Depth>1.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 3,09361>75% Grass cover, Good, HSG B 12,04255Woods, Good, HSG B 15,13556Weighted Average 15,135100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-3: Hydrograph Runoff 0.53 cfs 0.55 NRCC 24-hr D 0.5 25-Year Rainfall=6.16" 0.45 Runoff Area=15,135 sf 0.4 Runoff Volume=0.049 af 0.35 Runoff Depth>1.69" 0.3 Tc=6.0 min Flow (cfs) 0.25 CN=56 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 40 Summary for Subcatchment PR-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.22 cfs @ 12.11 hrs, Volume=0.105 af, Depth>4.13" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 25-Year Rainfall=6.16" Area (sf)CNDescription 7,46698Paved parking, HSG B 5,86661>75% Grass cover, Good, HSG B 13,33282Weighted Average 5,86644.00% Pervious Area 7,46656.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-4: Hydrograph Runoff 1.22 cfs NRCC 24-hr D 25-Year Rainfall=6.16" 1 Runoff Area=13,332 sf Runoff Volume=0.105 af Runoff Depth>4.13" Tc=6.0 min Flow (cfs) CN=82 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 41 Summary for Pond SIS-1: \[92\] Warning: Device #2 is above defined storage Inflow Area =0.436 ac,73.43% Impervious, Inflow Depth > 4.83" for 25-Year event Inflow=1.87 cfs @ 12.11 hrs, Volume=0.176 af Outflow=1.34 cfs @ 12.21 hrs, Volume=0.163 af, Atten= 28%, Lag= 6.0 min Discarded=0.04 cfs @ 7.90 hrs, Volume=0.072 af Primary=1.30 cfs @ 12.21 hrs, Volume=0.091 af Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Peak Elev= 96.51' @ 12.21 hrs Surf.Area= 784 sf Storage= 1,185 cf Plug-Flow detention time= 65.0 min calculated for 0.163 af (93% of inflow) Center-of-Mass det. time= 22.8 min ( 801.4 - 778.6 ) VolumeInvertAvail.StorageStorage Description #195.00'2,352 cf x 16 7.00'W x 7.00'L x 3.00'H Prismatoid DeviceRouting InvertOutlet Devices #1Primary95.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 95.00' / 94.00' S= 0.0100 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #2Device 198.00'4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3Device 195.75' C= 0.600 4.0" Vert. Orifice/Grate X 4.00 #4Discarded95.00' 2.410 in/hr Exfiltration over Surface area Max=0.04 cfs @ 7.90 hrs HW=95.03' (Free Discharge) Discarded OutFlow (Exfiltration Controls 0.04 cfs) 4=Exfiltration Max=1.28 cfs @ 12.21 hrs HW=96.50' (Free Discharge) Primary OutFlow (Passes 1.28 cfs of 2.98 cfs potential flow) 1=Culvert ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Orifice Controls 1.28 cfs @ 3.67 fps) 3=Orifice/Grate NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 42 Pond SIS-1: Hydrograph Inflow 1.87 cfs Outflow Discarded Inflow Area=0.436 ac Primary 2 Peak Elev=96.51' Storage=1,185 cf 1.34 cfs 1.30 cfs 1 Flow (cfs) 0.04 cfs 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 43 Summary for Link POA-1: Inflow Area =0.691 ac,50.47% Impervious, Inflow Depth > 3.92" for 25-Year event Inflow=2.63 cfs @ 12.11 hrs, Volume=0.226 af Primary=2.63 cfs @ 12.11 hrs, Volume=0.226 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 2.63 cfs 2.63 cfs Inflow Area=0.691 ac 2 Flow (cfs) 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 44 Summary for Link POA-2: Inflow Area =5.477 ac,53.41% Impervious, Inflow Depth > 3.88" for 25-Year event Inflow=19.24 cfs @ 12.12 hrs, Volume=1.769 af Primary=19.24 cfs @ 12.12 hrs, Volume=1.769 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow Primary 19.24 cfs 21 19.24 cfs 20 Inflow Area=5.477 ac 19 18 17 16 15 14 13 12 11 10 Flow (cfs) 9 8 7 6 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 45 Summary for Link POA-3: Inflow Area =0.347 ac,0.00% Impervious, Inflow Depth > 1.69" for 25-Year event Inflow=0.53 cfs @ 12.13 hrs, Volume=0.049 af Primary=0.53 cfs @ 12.13 hrs, Volume=0.049 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow Primary 0.53 cfs 0.53 cfs 0.55 Inflow Area=0.347 ac 0.5 0.45 0.4 0.35 0.3 Flow (cfs) 0.25 0.2 0.15 0.1 0.05 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 25-Year Rainfall=6.16" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 46 Summary for Link POA-4: Inflow Area =0.306 ac,56.00% Impervious, Inflow Depth > 4.13" for 25-Year event Inflow=1.22 cfs @ 12.11 hrs, Volume=0.105 af Primary=1.22 cfs @ 12.11 hrs, Volume=0.105 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow Primary 1.22 cfs 1.22 cfs Inflow Area=0.306 ac 1 Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 47 Time span=0.00-24.00 hrs, dt=0.10 hrs, 241 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=30,101 sf 50.47% Impervious Runoff Depth>6.51" Subcatchment PR-1: Tc=6.0 min CN=80 Runoff=4.29 cfs 0.375 af Runoff Area=107,780 sf 15.38% Impervious Runoff Depth>4.79" Subcatchment PR-2: Tc=6.0 min CN=66 Runoff=11.60 cfs 0.987 af Runoff Area=10,400 sf 100.00% Impervious Runoff Depth>8.69" Subcatchment PR-2A: Tc=6.0 min CN=98 Runoff=1.73 cfs 0.173 af Runoff Area=8,606 sf 41.33% Impervious Runoff Depth>6.01" Subcatchment PR-2B: Tc=6.0 min CN=76 Runoff=1.15 cfs 0.099 af Runoff Area=81,703 sf 100.00% Impervious Runoff Depth>8.69" Subcatchment PR-2C: Tc=6.0 min CN=98 Runoff=13.63 cfs 1.359 af Runoff Area=15,135 sf 0.00% Impervious Runoff Depth>3.56" Subcatchment PR-3: Tc=6.0 min CN=56 Runoff=1.19 cfs 0.103 af Runoff Area=13,332 sf 56.00% Impervious Runoff Depth>6.75" Subcatchment PR-4: Tc=6.0 min CN=82 Runoff=1.95 cfs 0.172 af Peak Elev=97.10' Storage=1,643 cf Inflow=2.88 cfs 0.272 af Pond SIS-1: Discarded=0.04 cfs 0.079 af Primary=1.83 cfs 0.179 af Outflow=1.87 cfs 0.258 af Inflow=4.29 cfs 0.375 af Link POA-1: Primary=4.29 cfs 0.375 af Inflow=31.06 cfs 2.899 af Link POA-2: Primary=31.06 cfs 2.899 af Inflow=1.19 cfs 0.103 af Link POA-3: Primary=1.19 cfs 0.103 af Inflow=1.95 cfs 0.172 af Link POA-4: Primary=1.95 cfs 0.172 af Total Runoff Area = 6.131 ac Runoff Volume = 3.267 af Average Runoff Depth = 6.40" 49.49% Pervious = 3.034 ac 50.51% Impervious = 3.097 ac NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 48 Summary for Subcatchment PR-1: \[49\] Hint: Tc<2dt may require smaller dt Runoff=4.29 cfs @ 12.11 hrs, Volume=0.375 af, Depth>6.51" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 15,19398Paved parking, HSG B 14,90861>75% Grass cover, Good, HSG B 30,10180Weighted Average 14,90849.53% Pervious Area 15,19350.47% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-1: Hydrograph Runoff 4.29 cfs NRCC 24-hr D 4 100-Year Rainfall=8.94" Runoff Area=30,101 sf 3 Runoff Volume=0.375 af Runoff Depth>6.51" Tc=6.0 min Flow (cfs) 2 CN=80 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 49 Summary for Subcatchment PR-2: \[49\] Hint: Tc<2dt may require smaller dt Runoff=11.60 cfs @ 12.12 hrs, Volume=0.987 af, Depth>4.79" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 16,57298Paved parking, HSG B 72,73161>75% Grass cover, Good, HSG B 18,47755Woods, Good, HSG B 107,78066Weighted Average 91,20884.62% Pervious Area 16,57215.38% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2: Hydrograph Runoff 11.60 cfs 12 NRCC 24-hr D 11 100-Year Rainfall=8.94" 10 Runoff Area=107,780 sf 9 8 Runoff Volume=0.987 af 7 Runoff Depth>4.79" 6 Tc=6.0 min Flow (cfs) 5 CN=66 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 50 Summary for Subcatchment PR-2A: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.73 cfs @ 12.11 hrs, Volume=0.173 af, Depth>8.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 10,40098Roofs, HSG B 10,400100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2A: Hydrograph Runoff 1.73 cfs NRCC 24-hr D 100-Year Rainfall=8.94" Runoff Area=10,400 sf Runoff Volume=0.173 af Runoff Depth>8.69" 1 Tc=6.0 min Flow (cfs) CN=98 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 51 Summary for Subcatchment PR-2B: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.15 cfs @ 12.11 hrs, Volume=0.099 af, Depth>6.01" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 3,55798Paved parking, HSG B 5,04961>75% Grass cover, Good, HSG B 8,60676Weighted Average 5,04958.67% Pervious Area 3,55741.33% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2B: Hydrograph Runoff 1.15 cfs NRCC 24-hr D 100-Year Rainfall=8.94" 1 Runoff Area=8,606 sf Runoff Volume=0.099 af Runoff Depth>6.01" Tc=6.0 min Flow (cfs) CN=76 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 52 Summary for Subcatchment PR-2C: \[49\] Hint: Tc<2dt may require smaller dt Runoff=13.63 cfs @ 12.11 hrs, Volume=1.359 af, Depth>8.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 81,70398Roofs, HSG B 81,703100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-2C: Hydrograph 15 Runoff 13.63 cfs 14 NRCC 24-hr D 13 12 100-Year Rainfall=8.94" 11 Runoff Area=81,703 sf 10 Runoff Volume=1.359 af 9 Runoff Depth>8.69" 8 7 Tc=6.0 min Flow (cfs) 6 CN=98 5 4 3 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 53 Summary for Subcatchment PR-3: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.19 cfs @ 12.12 hrs, Volume=0.103 af, Depth>3.56" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 3,09361>75% Grass cover, Good, HSG B 12,04255Woods, Good, HSG B 15,13556Weighted Average 15,135100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-3: Hydrograph Runoff 1.19 cfs NRCC 24-hr D 100-Year Rainfall=8.94" 1 Runoff Area=15,135 sf Runoff Volume=0.103 af Runoff Depth>3.56" Tc=6.0 min Flow (cfs) CN=56 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 54 Summary for Subcatchment PR-4: \[49\] Hint: Tc<2dt may require smaller dt Runoff=1.95 cfs @ 12.11 hrs, Volume=0.172 af, Depth>6.75" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs NRCC 24-hr D 100-Year Rainfall=8.94" Area (sf)CNDescription 7,46698Paved parking, HSG B 5,86661>75% Grass cover, Good, HSG B 13,33282Weighted Average 5,86644.00% Pervious Area 7,46656.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 6.0 Direct Entry, Subcatchment PR-4: Hydrograph Runoff 1.95 cfs 2 NRCC 24-hr D 100-Year Rainfall=8.94" Runoff Area=13,332 sf Runoff Volume=0.172 af Runoff Depth>6.75" 1 Tc=6.0 min Flow (cfs) CN=82 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 55 Summary for Pond SIS-1: \[92\] Warning: Device #2 is above defined storage Inflow Area =0.436 ac,73.43% Impervious, Inflow Depth > 7.48" for 100-Year event Inflow=2.88 cfs @ 12.11 hrs, Volume=0.272 af Outflow=1.87 cfs @ 12.23 hrs, Volume=0.258 af, Atten= 35%, Lag= 7.0 min Discarded=0.04 cfs @ 5.60 hrs, Volume=0.079 af Primary=1.83 cfs @ 12.23 hrs, Volume=0.179 af Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Peak Elev= 97.10' @ 12.23 hrs Surf.Area= 784 sf Storage= 1,643 cf Plug-Flow detention time= 51.2 min calculated for 0.258 af (95% of inflow) Center-of-Mass det. time= 19.5 min ( 790.7 - 771.2 ) VolumeInvertAvail.StorageStorage Description #195.00'2,352 cf x 16 7.00'W x 7.00'L x 3.00'H Prismatoid DeviceRouting InvertOutlet Devices #1Primary95.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 95.00' / 94.00' S= 0.0100 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #2Device 198.00'4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3Device 195.75' C= 0.600 4.0" Vert. Orifice/Grate X 4.00 #4Discarded95.00' 2.410 in/hr Exfiltration over Surface area Max=0.04 cfs @ 5.60 hrs HW=95.03' (Free Discharge) Discarded OutFlow (Exfiltration Controls 0.04 cfs) 4=Exfiltration Max=1.79 cfs @ 12.23 hrs HW=97.05' (Free Discharge) Primary OutFlow (Passes 1.79 cfs of 3.72 cfs potential flow) 1=Culvert ( Controls 0.00 cfs) 2=Sharp-Crested Rectangular Weir (Orifice Controls 1.79 cfs @ 5.13 fps) 3=Orifice/Grate NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 56 Pond SIS-1: Hydrograph Inflow 2.88 cfs Outflow Discarded Inflow Area=0.436 ac Primary 3 Peak Elev=97.10' Storage=1,643 cf 1.87 cfs 2 1.83 cfs Flow (cfs) 1 0.04 cfs 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 57 Summary for Link POA-1: Inflow Area =0.691 ac,50.47% Impervious, Inflow Depth > 6.51" for 100-Year event Inflow=4.29 cfs @ 12.11 hrs, Volume=0.375 af Primary=4.29 cfs @ 12.11 hrs, Volume=0.375 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-1: Hydrograph Inflow Primary 4.29 cfs 4.29 cfs Inflow Area=0.691 ac 4 3 Flow (cfs) 2 1 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 58 Summary for Link POA-2: Inflow Area =5.477 ac,53.41% Impervious, Inflow Depth > 6.35" for 100-Year event Inflow=31.06 cfs @ 12.11 hrs, Volume=2.899 af Primary=31.06 cfs @ 12.11 hrs, Volume=2.899 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-2: Hydrograph Inflow Primary 31.06 cfs 34 31.06 cfs 32 Inflow Area=5.477 ac 30 28 26 24 22 20 18 16 Flow (cfs) 14 12 10 8 6 4 2 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 59 Summary for Link POA-3: Inflow Area =0.347 ac,0.00% Impervious, Inflow Depth > 3.56" for 100-Year event Inflow=1.19 cfs @ 12.12 hrs, Volume=0.103 af Primary=1.19 cfs @ 12.12 hrs, Volume=0.103 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-3: Hydrograph Inflow Primary 1.19 cfs 1.19 cfs Inflow Area=0.347 ac 1 Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) NRCC 24-hr D 100-Year Rainfall=8.94" Post Development Printed 9/29/2025 Prepared by {enter your company name here} HydroCAD® 10.00-26 s/n 07576 © 2020 HydroCAD Software Solutions LLC Page 60 Summary for Link POA-4: Inflow Area =0.306 ac,56.00% Impervious, Inflow Depth > 6.75" for 100-Year event Inflow=1.95 cfs @ 12.11 hrs, Volume=0.172 af Primary=1.95 cfs @ 12.11 hrs, Volume=0.172 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.10 hrs Link POA-4: Hydrograph Inflow Primary 1.95 cfs 1.95 cfs 2 Inflow Area=0.306 ac 1 Flow (cfs) 0 0123456789101112131415161718192021222324 Time (hours) 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, the Stormwater Report (which should provide more substantive and detailed information) but is offered use only the tab here as a tool to help the applicant organize their Stormwater Management documentation for their key to move your 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 certified by a Registered Professional Engineer (RPE) licensed in the Commonwealth. The Stormwater Report must include: The Stormwater Checklist completed and stamped by a Registered Professional Engineer (see 1 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 2 by Standard 8 Operation and Maintenance Plan required by Standard 9 In addition to all plans and supporting information, the Stormwater Report must include a brief narrative describing stormwater management practices, including environmentally sensitive site design and LID techniques, along with a diagram depicting runoff through the proposed BMP treatment train. Plans are required to show existing and proposed conditions, identify all wetland resource areas, NRCS soil types, critical areas, Land Uses with Higher Potential Pollutant Loads (LUHPPL), and any areas on the site where infiltration rate is greater than 2.4 inches per hour. The Plans shall identify the drainage areas for both existing and proposed conditions at a scale that enables verification of supporting calculations. As noted in the Checklist, the Stormwater Management Report shall document compliance with each of the Stormwater Management Standards as provided in the Massachusetts Stormwater Handbook. The soils evaluation and calculations shall be done using the methodologies set forth in Volume 3 of the Massachusetts Stormwater Handbook. To ensure that the Stormwater Report is complete, applicants are required to fill in the Stormwater Report Checklist by checking the box to indicate that the specified information has been included in the Stormwater Report. If any of the information specified in the checklist has not been submitted, the applicant must provide an explanation. The completed Stormwater Report Checklist and Certification must be submitted with the Stormwater Report. 1 The Stormwater Report may also include the Illicit Discharge Compliance Statement required by Standard 10. If not included in the Stormwater Report, the Illicit Discharge Compliance Statement must be submitted prior to the discharge of stormwater runoff to the post-construction best management practices. 2 For some complex projects, it may not be possible to include the Construction Period Erosion and Sedimentation Control Plan in the Stormwater Report. In that event, the issuing authority has the discretion to issue an Order of Conditions that approves the project and includes a condition requiring the proponent to submit the Construction Period Erosion and Sedimentation Control Plan before commencing any land disturbance activity on the site. SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 1of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report B.Stormwater Checklist and Certification The following checklist is intended to serve as a guide for applicants as to the elements that ordinarily need to be addressed in a complete Stormwater Report. The checklist is also intended to provide conservation commissions and other reviewing authorities with a summary of the components necessary for a comprehensive Stormwater Report that addresses the ten Stormwater Standards. Note:Because stormwater requirements vary from project to project, it is possible that a complete Stormwater Report may not include information on some of the subjects specified in the Checklist. If it is determined that a specific item does not apply to the project under review,please note that the item is not applicable (N.A.) and provide the reasons for that determination. A complete checklist must include the Certification set forth below signed by the Registered Professional Engineer who prepared the Stormwater Report. Registered Professional Engineer’s Certification I have reviewed the Stormwater Report, including the soil evaluation, computations, Long-term Pollution Prevention Plan, the Construction Period Erosion and Sedimentation Control Plan (if included), the Long- term Post-Construction Operation and Maintenance Plan, the Illicit Discharge Compliance Statement (if included) and the plans showing the stormwater management system, and have determined that they have been prepared in accordance with the requirements of the Stormwater Management Standards as further elaborated by the Massachusetts Stormwater Handbook. I have also determined that the information presented in the Stormwater Checklist is accurate and that the information presented in the Stormwater Report accurately reflects conditions at the site as of the date of this permit application. Registered Professional Engineer Block and Signature Signature and Date Checklist Project Type:Is the application for new development, redevelopment, or a mix of new and redevelopment? New development Redevelopment Mix of New Development and Redevelopment SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 2of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report Checklist(continued) LID Measures: Stormwater Standards require LID measures to be considered. Document what environmentally sensitive design and LID Techniques were considered during the planning and design of the project: No disturbance to any Wetland Resource Areas Site Design Practices (e.g. clustered development, reduced frontage setbacks) Reduced Impervious Area (Redevelopment Only) Minimizing disturbance to existing trees and shrubs LID Site Design Credit Requested: Credit 1 Credit 2 Credit 3 Use of “country drainage” versus curb and gutter conveyance and pipe Bioretention Cells (includes Rain Gardens) Constructed Stormwater Wetlands (includes Gravel Wetlands designs) Treebox Filter Water Quality Swale Grass Channel Green Roof Other (describe): 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. SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 3of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report Checklist(continued) Standard 2: Peak Rate Attenuation Standard 2 waiver requested because the project is located in land subject to coastalstorm 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. 1 StaticSimple DynamicDynamic 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. 21E sites pursuant to 310 CMR 40.0000 Solid Waste Landfill pursuant to 310 CMR 19.000 Project is otherwise subject to Stormwater Management Standards only to the maximum extent practicable. Calculations showing that the infiltration BMPs will drain in 72 hours are provided. Property includes a M.G.L. c. 21E site or a solid waste landfill and a mounding analysis is included. 1 80% TSS removal is required prior to discharge to infiltration BMP if Dynamic Field method is used. SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 4of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report Checklist(continued) Standard 3: Recharge(continued) The infiltration BMP is used to attenuate peak flows during storms greater than or equal to the 10- year 24-hour storm and separation to seasonal high groundwater is less than 4 feet and a mounding analysis is provided. Documentation is provided showing that infiltration BMPs do not adversely impact nearby wetland resource areas. Standard 4: Water Quality The Long-Term Pollution Prevention Plan typically includes the following: Good housekeeping practices; Provisions for storing materials and waste products inside or under cover; Vehicle washing controls; Requirements for routine inspections and maintenance of stormwater BMPs; Spill prevention and response plans; Provisions for maintenance of lawns, gardens, and other landscaped areas; Requirements for storage and use of fertilizers, herbicides, and pesticides; Pet waste management provisions; Provisions for operation and management of septic systems; Provisions for solid waste management; Snow disposal and plowing plans relative to Wetland Resource Areas; Winter Road Salt and/or Sand Use and Storage restrictions; Streetsweeping 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. SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 5of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report Checklist(continued) Standard 4: Water Quality(continued) The BMP is sized (and calculations provided) based on: The ½” or 1” Water Quality Volume or The equivalent flow rate associated with the Water Quality Volume and documentation is provided showing that the BMP treats the required water quality volume. The applicant proposes to use proprietary BMPs, and documentation supporting use of proprietary BMP and proposed TSS removal rate is provided. This documentation may be in the form of the proprietyBMP checklist found in Volume 2, Chapter 4 of the Massachusetts Stormwater Handbook and submitting copies of the TARP Report, STEP Report, and/or other third party studies verifying performance of the proprietary BMPs. A TMDL exists that indicates a need to reduce pollutants other than TSS and documentation showing that the BMPs selected are consistent with the TMDL is provided. Standard 5: Land Uses With Higher Potential Pollutant Loads (LUHPPLs) The NPDES Multi-Sector General Permit covers the land use and the Stormwater Pollution Prevention Plan (SWPPP) has been included with the Stormwater Report. The NPDES Multi-Sector General Permit covers the land use and the SWPPP will be submitted prior to the discharge of stormwater to the post-construction stormwater BMPs. The NPDES Multi-Sector General Permit does not cover the land use. LUHPPLs are located at the site and industry specific source control and pollution prevention measures have been proposed to reduce or eliminate the exposure of LUHPPLs to rain, snow, snow melt and runoff, and been included in the long term Pollution Prevention Plan. All exposure has been eliminated. All exposure has not been eliminated and all BMPs selected are on MassDEP LUHPPL list. The LUHPPL has the potential to generate runoff with moderate to higher concentrations of oil and grease (e.g. all parking lots with >1000 vehicle trips per day) and the treatment train includes an oil grit separator, a filtering bioretention area, a sand filter or equivalent. Standard 6: Critical Areas The discharge is near or to a critical area and the treatment train includes only BMPs that MassDEP has approved for stormwater discharges to or near that particular class of critical area. Critical areas and BMPs are identified in the Stormwater Report. SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 6of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report Checklist(continued) Standard 7: Redevelopments and Other Projects Subject to the Standards only to the maximum extent practicable The project is subject to the Stormwater Management Standards only to the maximum Extent Practicable as a: Limited Project Small Residential Projects: 5-9 single family houses or 5-9 units in a multi-family development provided there is no discharge that may potentially affect a critical area. Small Residential Projects: 2-4 single family houses or 2-4 units in a multi-family development with a discharge to a critical area Marina and/or boatyard provided the hull painting, service and maintenance areas are protected from exposure to rain, snow, snow melt and runoff Bike Path and/or Foot Path Redevelopment Project Redevelopment portion of mix of new and redevelopment. Certain standards are not fully met (StandardNo. 1, 8, 9, and 10 must always be fully met) and an explanation of why these standards are not met is contained in the Stormwater Report. The project involves redevelopment and a description of all measures that have been taken to improve existing conditions is provided in the Stormwater Report. The redevelopment checklist found in Volume 2 Chapter 3 of the Massachusetts Stormwater Handbook may be used to document that the proposed stormwater management system (a) complies with Standards 2, 3 and the pretreatment and structural BMP requirements of Standards 4-6 to the maximum extent practicable and (b) improves existing conditions. Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan must include the following information: Narrative; Construction Period Operation and Maintenance Plan; Names of Persons or Entity Responsible for Plan Compliance; Construction Period Pollution Prevention Measures; Erosion and Sedimentation Control Plan Drawings; Detail drawings and specifications for erosion control BMPs, including sizing calculations; Vegetation Planning; Site Development Plan; Construction Sequencing Plan; Sequencing of Erosion and Sedimentation Controls; Operation and Maintenance of Erosion and Sedimentation Controls; Inspection Schedule; Maintenance Schedule; Inspection and Maintenance Log Form. A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan containing the information set forth above has been included in the Stormwater Report. SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 7of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection -Wetlands Program Checklist for Stormwater Report Checklist(continued) Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control (continued) The project is highly complex and information is included in the Stormwater Report that explains why it is not possible to submit the Construction Period Pollution Prevention and Erosion and SedimentationControl 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 ConstructionGeneral 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 ofthe 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. SW Checklist.doc• 04/01/08Stormwater Report Checklist • Page 8of 8 OPERATION AND MAINTENANCE PLAN FOR EAST MILL RESIDENTIAL DEVELOPMENT 0 PRESCOTT STREET NORTH ANDOVER, MA 01845 PREPARED FOR: RCG, LLC 17 Ivaloo Street, Suite 100 Somerville, MA 02143 PREPARED BY: C IVIL D ESIGN G ROUP, LLC 4 HIGH STREET, SUITE 155 NORTH ANDOVER, MA 01845 DATE: OCTOBER 2025 TABLE OF CONTENTS 1.0 INTRODUCTION………………………………………………………………………..............................2 2.0 LONG TERM POLLUTION PREVENTION PLAN (LTPPP)………………………..………………...2 3.0 STORMWATER MANAGEMENT SYSTEM……………………………………………........................3 4.0 SNOW MANAGEMENT AND DEICING CONTROL………...………………………………………...4 5.0 ILLICIT DISCHARGE STATEMENT……...…………………………………………….........................4 APPENDIX A – OPERATION AND MAINTENANCE REPORT FORM FIGURE 1 – BMP LOCATION PLAN 1 p: 978-794-5400 f : 978.965.3971 www.cdgengineering.com OPERATION AND MAINTENANCE PLAN 1.0 INTRODUCTION In accordance with the standards set forth by the Massachusetts Department of Environmental Protection (MADEP) Stormwater Management Policy, Civil Design Group, LLC has prepared the following Operations and Maintenance (O&M) Plan for a new residential apartment building at the East Mill Campus located at the site below. PROPERTY INFORMATION PROPERTY ADDRESSLANDOWNER & STORMWATER MANAGEMENT SYSTEM OWNER Owner: RCG, LLC EAST MILL RESIDENTIAL DEVELOPMENT Contact: Mr. David Steinbergh 0 PRESCOTT STREET Phone: 617-625-8315 NORTH ANDOVER, MA 01845 Email: dsteinbergh@rcg-llc.com The landowner shall be responsible for the long-term operation and maintenance of the site and the stormwater management system and shall be responsible for record keeping of inspections, maintenanceand repairs. If the site owner changes, the new site owner shall assume all responsibilities outlined in this O&M plan. The site owner shall hire a qualified professional to conduct scheduled inspections and maintain records in accordance with the inspection schedule outline enclosed within this document. Site Engineer: Civil Design Group, LLC Address: 4 High Street, Suite 155, North Andover, MA 01845 Office Phone: 978-794-5400 Contact: Philip Henry, P.E. 2.0 LONG TERM POLLUTION PREVENTION PLAN (LTPPP) In accordance with Standard #4 from the MADEP Stormwater Management Policy, the following LTPPP has been prepared as part of this O&M Plan. The purpose of the LTPPP is to identify potential pollutant sources in stormwater discharges and implement prevention measures prior to affecting downstream resource areas. Housekeeping: The site shall be kept in a clean and working order. Substances and materials to be used on site that consistent with the nature of business shall be protected from the elements by storing indoors or in containers with appropriate lids. Proper disposal and care shall be followed when disposing of empty containers. Solid Waste: Solid waste materials shall be stored in the dumpsters provided on site. The dumpster enclosure shall be kept closed when not in use and the trash shall not be left outside of the enclosure. The owner shall contract with a waste management company to properly dispose of waste material. The dumpsters shall be emptied on a regular basis. Pet Waste Management: Pet waste is not anticipated based on the proposed use of the site. 2 p: 978-794-5400 f : 978.965.3971 www.cdgengineering.com Petroleum Products: Petroleum products shallbe stored in sealed containersandclearly labeled. Petroleum storage tanks shall be located a minimum of 100 linear feet from wetland resource areas, drainage ways, inlets and surface waters unless stored within a building. Petroleum storage tanks shallbe equipped with a secondary means of containment designed to provide a containment volume that is equal to 110% of the volume of the largest tank unless otherwise required. Drip pans or other form of containment shall be provided for all dispensers. Any asphalt substances used onsite will be applied according to the manufacturer's recommendations. Fertilizers, Herbicides and Pesticides: Fertilizers, herbicides and pesticides shall be used in the minimum amounts recommended by the manufacturer and applied to limit contact with stormwater. These products shall be stored in containers indoors. Paints and Cleaning Solvents: Paints and containers shall be properly stored in their original containers. Disposal of these products and their containers shall be in accordance with the manufacturer’s recommendations. Spill Prevention and Response: In the event of a spill of a hazardous substance the following response action items shall be followed in order to prevent or minimize discharge to the stormwater management system. 1. Spills shall be immediately addressed. 2. Spills of hazardous substances shall be remediated using the manufacturers’ protocol for cleanup. 3. Vehicular and fuel spills shall be remediated in accordance to local and state regulations. 4. The following equipment and materials shall be present on site and shall be clearly identifiable: a. Absorbent materials, brooms, dust pans, mops, rags, gloves, goggles, trash containers, etc. 5. Spills that are toxic or hazardous in nature shall be reported to the MA DEP and professional emergency contractor. 6. The owner shall designate individuals who will receive spill prevention and response training. These individuals will each become responsible for a particular phase of prevention and response. The names of these personnel shall be posted in the material storage area and in the management office. 3.0 STORMWATER MANAGEMENT SYSTEM The components of the stormwater management system shall be inspected, monitored and maintained in accordance with the following to ensure that the on-site stormwater management/BMP facilities for the project function as intended. Routine inspection and proper maintenance of these individual components is essential to providing the long-term enhancement of both the quality and quantity of the runoff from the site. The proposed stormwater management Best Management Practices (BMP’s ) have been designed to collect and convey runoff from developed areas in accordance with the Massachusetts DEP’s Stormwater Management Policy. Using the rational method to determine peak runoff flows, the onsite drainage system is designed for the 25-year storm event. The drainage system consists of catch basins, yard drains, a subsurface infiltration system, a water quality unit and associated piping and drainage manholes. 3 p: 978-794-5400 f : 978.965.3971 www.cdgengineering.com Street Sweeping Sweeping shall be performed twice a year, once in the spring and once in the fall, within the parking lot and driveway areas to reduce the amount of sediment and trash enteringthe catch basins. Deep Sump Hooded Catch Basins Stormwater runoff from proposed pavement areas is directed via curbing and site grading to catch basins with deep sumps and hooded outlets and trench drains. These structures are designed to trap and remove sediment and larger particles from the stormwater and improve the performance of subsequent BMP’s. The catch basin sumps are a minimum of 4’ in depth and a routine inspection and cleaning schedule shall be followed to ensure optimal effectiveness. Inspection Frequency: Quarterly Cleaning Threshold(s): 18” sediment in sump; discernable layer of oil on surface; floating trash Equipment: Clamshell or vactor Subsurface Infiltration System (SIS) Subsurface infiltration system is designed to infiltrate runoff from the site. The system is comprised of pipe and stone. The system is equipped with an inspection port to facilitate inspection for sediment accumulation. Inspection Frequency: Quarterly Cleaning Threshold(s): 4” sediment Equipment: Water jet and vactor Hydrodynamic Separator Hydrodynamic Separators are designed to remove heavy particles, floating debris and hydrocarbons from stormwater. Stormwater enters the system where floatables and oils are separated prior to the clarified stormwater runoff discharging to an outlet pipe. See the attached Stormceptor product description sheets for additional information, including maintenance recommendations. Inspection Frequency: Quarterly Cleaning Threshold(s): Per manufacturer’s recommendations Equipment: Vactor 4.0 SNOW MANAGEMENT AND DEICING CONTROL The Owner shall contract with a company to properly clear and remove snow. The contractor shall be responsible for maintaining all roads, driveways, parking lots, sidewalks and pedestrian access onsite as well as along the right-of-way frontage. Snow shall be piled in the designated areas snow storage areas to the extent practicable. Snow shall be removed from the siteif the capacity of the designated areas is reached, and disposed of in accordance with applicable regulationsand requirements. Deicing chemicals shall be kept indoors in a safe location and shall be clearly labeled. Deicing solutions such as calcium chloride, rock salt and/or sand may be used unless otherwise restricted by the municipality. Deicing methods shall be used in conjunction with snow removal to maintain safe pedestrian and vehicular access. 4 p: 978-794-5400 f : 978.965.3971 www.cdgengineering.com 5.0 ESTIMATED OPERATION AND MAINTENANCE BUDGET The estimated average annual operating and maintenance budget for the proposed system is shown below: Catch Basins: $200 each Proprietary Separator: $1,000 each Subsurface Infiltration System: $1,500 each Routine maintenance = $2,000 o Removal of trash o Annual street sweeping o Pipe network/outfall inspections 6.0 ILLICIT DISCHARGE STATEMENT The proposed stormwater management system consists of deep sump hooded catch basins, manholes, a hydrodynamic separator, and associated piping which is intended to collect and convey stormwater discharges from the site. The stormwater management system is not intended to convey any illicit discharges and or pollutants and as such, control measures that are identified within this report shall be strictly adhered to in order to minimize the risk of contamination. Any unknown existing illicit discharges that are discovered as part of the redevelopment of the subject site shall be eliminated in accordance with local, state and federal regulations. 5 p: 978-794-5400 f : 978.965.3971 www.cdgengineering.com APPENDIX-A OPERATION AND MAINTENANCE REPORT FORM 21 High Street, Suite 207 S TORMWATER D IVISION North Andover, MA 01845 Tel 978.794.5400 www.cdgengineering.com OF C IVIL D ESIGN G ROUP, LLC QUARTERLY STORMWATER INSPECTION REPORT Site:Residential Development Date: Address:Prescott Street, North Andover, MA 01845 Time: Inspector:Weather: BMP UnitSedimentOilLast Trash Cover # (inches) (inches) Cleaned Attention Recommended EXISTING OUTFALLS IN SWALE DMH-9 (HS5) SUBSURFACE INFILTRATION SYSTEM (SIS) Unit Sediment Oil Last Trash Grate # (inches) (inches) Cleaned Attention Recommended SIS-1 1 2 3 M W E. U I I G V N I P M W 7 O O N/F 2 D D 5 N A 1 O E . C M K B PLAN FIGURE-1 BMP LOCATION ESIGN D ROUP, LLC www.cdgengineering.com 4 HIGH STREET SUITE 155 NORTH ANDOVER, MA 01845 IVIL p: 978-794-5400 f: 978-965-3971 G C P E R D L A W . O N/F N O T F I BK. 1410 PG. 17 L C B R I C 1 K S T O R Y B U I L D I N G 2 2