JMA02P003 262 270 Main Street Development Stormwater Management Report

Proposed Flows NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/26/2026 HydroCAD® 10.20-8a Sampler s/n S05110 © 2025 HydroCAD Software Solutions LLC This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Hydrograph for Pond 2P: Basin A Time Inflow Storage Elevation Outflow Discarded Primary (hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs) 0.00 0.00 0 95.70 0.00 0.00 0.00 2.50 0.02 17 95.72 0.02 0.02 0.00 5.00 0.04 59 95.77 0.02 0.02 0.00 7.50 0.05 206 95.94 0.02 0.02 0.00 10.00 0.08 509 96.24 0.02 0.02 0.00 12.50 0.19 2,423 97.39 0.24 0.02 0.21 15.00 0.07 1,955 97.08 0.13 0.02 0.10 17.50 0.05 1,494 96.81 0.08 0.02 0.05 20.00 0.04 1,327 96.71 0.05 0.02 0.02 22.50 0.03 1,255 96.67 0.03 0.02 0.01 25.00 0.00 1,121 96.59 0.02 0.02 0.00 27.50 0.00 897 96.46 0.02 0.02 0.00 30.00 0.00 674 96.34 0.02 0.02 0.00 32.50 0.00 451 96.21 0.02 0.02 0.00 35.00 0.00 228 95.97 0.02 0.02 0.00 37.50 0.00 10 95.71 0.01 0.01 0.00 40.00 0.00 0 95.70 0.00 0.00 0.00 42.50 0.00 0 95.70 0.00 0.00 0.00 45.00 0.00 0 95.70 0.00

0 95.70 0.00 0.00 0.00 42.50 0.00 0 95.70 0.00 0.00 0.00 45.00 0.00 0 95.70 0.00 0.00 0.00 47.50 0.00 0 95.70 0.00 0.00 0.00 50.00 0.00 0 95.70 0.00 0.00 0.00 52.50 0.00 0 95.70 0.00 0.00 0.00 55.00 0.00 0 95.70 0.00 0.00 0.00 57.50 0.00 0 95.70 0.00 0.00 0.00 60.00 0.00 0 95.70 0.00 0.00 0.00 62.50 0.00 0 95.70 0.00 0.00 0.00 65.00 0.00 0 95.70 0.00 0.00 0.00 67.50 0.00 0 95.70 0.00 0.00 0.00 70.00 0.00 0 95.70 0.00 0.00 0.00

Proposed Flows NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/26/2026 HydroCAD® 10.20-8a Sampler s/n S05110 © 2025 HydroCAD Software Solutions LLC This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Summary for Pond 5P: Porous Pavement B Inflow Area = 16,284 sf, 94.43% Impervious, Inflow Depth = 4.96" for 10-Year-Current event Inflow = 2.22 cfs @ 12.06 hrs, Volume= 6,725 cf Outflow = 0.13 cfs @ 13.33 hrs, Volume= 6,725 cf, Atten= 94%, Lag= 75.9 min Discarded = 0.07 cfs @ 9.40 hrs, Volume= 5,536 cf Primary = 0.06 cfs @ 13.33 hrs, Volume= 1,189 cf Routed to nonexistent node 6L Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 97.45' @ 13.33 hrs Surf.Area= 5,690 sf Storage= 2,539 cf Plug-Flow detention time= 230.3 min calculated for 6,720 cf (100% of inflow) Center-of-Mass det. time= 230.4 min ( 978.6 - 748.2 ) Volume Invert Avail.Storage Storage Description #1 97.00' 14,225 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 97.00 5,690 0 0 98.00 5,690 5,690 5,690 99.00 5,690 5,690 11,380 99.50 5,690 2,845 14,225 Device Routing Invert Outlet Devices #1 Primary 97.20' 2.5" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Discarded 97.00' 0.500 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.07 cfs @ 9.40 hrs HW=97.03' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.07 cfs) Primary OutFlow Max=0.06 cfs @ 13.33 hrs HW=97.45' (Free Discharge) 1=Orifice/Grate

ed OutFlow Max=0.07 cfs @ 9.40 hrs HW=97.03' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.07 cfs) Primary OutFlow Max=0.06 cfs @ 13.33 hrs HW=97.45' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.06 cfs @ 1.82 fps)

Proposed Flows NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/26/2026 HydroCAD® 10.20-8a Sampler s/n S05110 © 2025 HydroCAD Software Solutions LLC This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Pond 5P: Porous Pavement B Hydrograph 2.22 cfs Inflow Outflow Inflow Area=16,284 sf Discarded Primary Peak Elev=97.45' 2 Storage=2,539 cf Flow (cfs) 1 0.13 cfs 0.07 cfs 0.06 cfs 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours)

Proposed Flows NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/26/2026 HydroCAD® 10.20-8a Sampler s/n S05110 © 2025 HydroCAD Software Solutions LLC This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Pond 5P: Porous Pavement B Stage-Discharge Total Discarded Primary 99 Elevation (feet) 98 Orifice/Grate Exfiltration 97 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2 0.22 0.24 0.26 0.28 0.3 Discharge (cfs)

Proposed Flows NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/26/2026 HydroCAD® 10.20-8a Sampler s/n S05110 © 2025 HydroCAD Software Solutions LLC This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Pond 5P: Porous Pavement B Stage-Area-Storage Surface/Horizontal/Wetted Area (sq-ft) 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 Surface Storage 99 Elevation (feet) 98 Custom Stage Data 97 0 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,000 10,000 11,000 12,000 13,000 14,000 Storage (cubic-feet)

Proposed Flows NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/26/2026 HydroCAD® 10.20-8a Sampler s/n S05110 © 2025 HydroCAD Software Solutions LLC This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Hydrograph for Pond 5P: Porous Pavement B Time Inflow Storage Elevation Outflow Discarded Primary (hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs) 0.00 0.00 0 97.00 0.00 0.00 0.00 2.50 0.02 36 97.01 0.02 0.02 0.00 5.00 0.04 76 97.01 0.04 0.04 0.00 7.50 0.05 105 97.02 0.05 0.05 0.00 10.00 0.08 177 97.03 0.07 0.07 0.00 12.50 0.22 2,441 97.43 0.12 0.07 0.06 15.00 0.08 2,335 97.41 0.12 0.07 0.05 17.50 0.05 1,891 97.33 0.09 0.07 0.03 20.00 0.04 1,554 97.27 0.08 0.07 0.01 22.50 0.03 1,242 97.22 0.07 0.07 0.00 25.00 0.00 796 97.14 0.07 0.07 0.00 27.50 0.00 203 97.04 0.07 0.07 0.00 30.00 0.00 3 97.00 0.00 0.00 0.00 32.50 0.00 0 97.00 0.00 0.00 0.00 35.00 0.00 0 97.00 0.00 0.00 0.00 37.50 0.00 0 97.00 0.00 0.00 0.00 40.00 0.00 0 97.00 0.00 0.00 0.00 42.50 0.00 0 97.00 0.00 0.00 0.00 45.00 0.00 0 97.00 0.00

0 97.00 0.00 0.00 0.00 42.50 0.00 0 97.00 0.00 0.00 0.00 45.00 0.00 0 97.00 0.00 0.00 0.00 47.50 0.00 0 97.00 0.00 0.00 0.00 50.00 0.00 0 97.00 0.00 0.00 0.00 52.50 0.00 0 97.00 0.00 0.00 0.00 55.00 0.00 0 97.00 0.00 0.00 0.00 57.50 0.00 0 97.00 0.00 0.00 0.00 60.00 0.00 0 97.00 0.00 0.00 0.00 62.50 0.00 0 97.00 0.00 0.00 0.00 65.00 0.00 0 97.00 0.00 0.00 0.00 67.50 0.00 0 97.00 0.00 0.00 0.00 70.00 0.00 0 97.00 0.00 0.00 0.00

Proposed Flows NOAA10 24-hr D 100-Year-Current Rainfall=9.18" Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 5/26/2026 HydroCAD® 10.20-8a Sampler s/n S05110 © 2025 HydroCAD Software Solutions LLC This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and educational use ONLY. For actual design or modeling applications you MUST use a full version of HydroCAD which may be purchased at www.hydrocad.net. Full programs also include complete technical support,training materials, and additional features which are essential for actual design work. Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S: Proposed Impervious Runoff Area=13,934 sf 100.00% Impervious Runoff Depth=8.94" Tc=1.0 min CN=98 Runoff=3.36 cfs 10,380 cf Subcatchment 3S: Proposed Pervious Runoff Area=907 sf 0.00% Impervious Runoff Depth=5.99" Tc=1.0 min CN=74 Runoff=0.17 cfs 453 cf Subcatchment 4S: Proposed Impervious Runoff Area=15,377 sf 100.00% Impervious Runoff Depth=8.94" Tc=1.0 min CN=98 Runoff=3.71 cfs 11,455 cf Pond 2P: Basin A Peak Elev=97.74' Storage=2,895 cf Inflow=3.36 cfs 10,380 cf Discarded=0.02 cfs 3,345 cf Primary=3.04 cfs 7,035 cf Outflow=3.07 cfs 10,380 cf Pond 5P: Porous Pavement B Peak Elev=97.93' Storage=5,275 cf Inflow=3.88 cfs 11,908 cf Discarded=0.07 cfs 7,190 cf Primary=0.13 cfs 4,718 cf Outflow=0.20 cfs 11,908 cf Total Runoff Area = 30,218 sf Runoff Volume = 22,289 cf Average Runoff Depth = 8.85" 3.00% Pervious = 907 sf 97.00% Impervious = 29,311 sf