JMA02P003 262 270 Main Street Development Stormwater Management Report

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 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. 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=5.09" Tc=1.0 min CN=98 Runoff=1.95 cfs 5,913 cf Subcatchment 3S: Proposed Pervious Runoff Area=907 sf 0.00% Impervious Runoff Depth=2.63" Tc=1.0 min CN=74 Runoff=0.08 cfs 199 cf Subcatchment 4S: Proposed Impervious Runoff Area=15,377 sf 100.00% Impervious Runoff Depth=5.09" Tc=1.0 min CN=98 Runoff=2.15 cfs 6,526 cf Pond 2P: Basin A Peak Elev=97.42' Storage=2,470 cf Inflow=1.95 cfs 5,913 cf Discarded=0.02 cfs 3,179 cf Primary=0.34 cfs 2,735 cf Outflow=0.36 cfs 5,913 cf Pond 5P: Porous Pavement B Peak Elev=97.45' Storage=2,539 cf Inflow=2.22 cfs 6,725 cf Discarded=0.07 cfs 5,536 cf Primary=0.06 cfs 1,189 cf Outflow=0.13 cfs 6,725 cf Total Runoff Area = 30,218 sf Runoff Volume = 12,638 cf Average Runoff Depth = 5.02" 3.00% Pervious = 907 sf 97.00% Impervious = 29,311 sf

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 Subcatchment 1S: Proposed Impervious Runoff = 1.95 cfs @ 12.06 hrs, Volume= 5,913 cf, Depth= 5.09" Routed to Pond 2P : Basin A Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Area (sf) CN Description 13,934 98 Roofs, HSG C 13,934 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.0 Direct Entry, Subcatchment 1S: Proposed Impervious Hydrograph Runoff 1.95 cfs 2 NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Runoff Area=13,934 sf Runoff Volume=5,913 cf Runoff Depth=5.09" Flow (cfs)

Runoff Depth=5.09" Flow (cfs) Tc=1.0 min 1 CN=98 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. Hydrograph for Subcatchment 1S: Proposed Impervious Time Precip. Excess Runoff Time Precip. Excess Runoff (hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs) 0.00 0.00 0.00 0.00 47.00 5.33 5.09 0.00 1.00 0.07 0.00 0.01 48.00 5.33 5.09 0.00 2.00 0.15 0.04 0.02 49.00 5.33 5.09 0.00 3.00 0.24 0.10 0.02 50.00 5.33 5.09 0.00 4.00 0.35 0.19 0.03 51.00 5.33 5.09 0.00 5.00 0.47 0.29 0.04 52.00 5.33 5.09 0.00 6.00 0.59 0.40 0.04 53.00 5.33 5.09 0.00 7.00 0.73 0.54 0.04 54.00 5.33 5.09 0.00 8.00 0.89 0.68 0.05 55.00 5.33 5.09 0.00 9.00 1.05 0.84 0.06 56.00 5.33 5.09 0.00 10.00 1.28 1.06 0.08 57.00 5.33 5.09 0.00 11.00 1.58 1.36 0.13 58.00 5.33 5.09 0.00 12.00 2.52 2.29 1.20 59.00 5.33 5.09 0.00 13.00 3.75 3.52 0.13 60.00 5.33 5.09 0.00 14.00 4.05 3.82 0.08 61.00 5.33 5.09 0.00 15.00 4.28 4.04 0.07 62.00 5.33 5.09 0.00 16.00 4.44 4.21 0.05 63.00 5.33 5.09 0.00 17.00 4.60 4.36 0.05 64.00 5.33 5.09 0.00 18.00 4.74 4.50 0.04 65.00 5.33 5.09 0.00 19.00 4.86 4.63 0.04 66.00 5.33 5.09 0.00 20.00 4.98 4.74 0.04 67.00

0 18.00 4.74 4.50 0.04 65.00 5.33 5.09 0.00 19.00 4.86 4.63 0.04 66.00 5.33 5.09 0.00 20.00 4.98 4.74 0.04 67.00 5.33 5.09 0.00 21.00 5.09 4.85 0.03 68.00 5.33 5.09 0.00 22.00 5.18 4.94 0.03 69.00 5.33 5.09 0.00 23.00 5.26 5.02 0.02 70.00 5.33 5.09 0.00 24.00 5.33 5.09 0.02 71.00 5.33 5.09 0.00 25.00 5.33 5.09 0.00 72.00 5.33 5.09 0.00 26.00 5.33 5.09 0.00 27.00 5.33 5.09 0.00 28.00 5.33 5.09 0.00 29.00 5.33 5.09 0.00 30.00 5.33 5.09 0.00 31.00 5.33 5.09 0.00 32.00 5.33 5.09 0.00 33.00 5.33 5.09 0.00 34.00 5.33 5.09 0.00 35.00 5.33 5.09 0.00 36.00 5.33 5.09 0.00 37.00 5.33 5.09 0.00 38.00 5.33 5.09 0.00 39.00 5.33 5.09 0.00 40.00 5.33 5.09 0.00 41.00 5.33 5.09 0.00 42.00 5.33 5.09 0.00 43.00 5.33 5.09 0.00 44.00 5.33 5.09 0.00 45.00 5.33 5.09 0.00 46.00 5.33 5.09 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 Subcatchment 3S: Proposed Pervious Runoff = 0.08 cfs @ 12.07 hrs, Volume= 199 cf, Depth= 2.63" Routed to Pond 5P : Porous Pavement B Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA10 24-hr D 10-Year-Current Rainfall=5.33" Area (sf) CN Description 907 74 >75% Grass cover, Good, HSG C 907 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.0 Direct Entry, Subcatchment 3S: Proposed Pervious Hydrograph 0.085 Runoff 0.08 cfs 0.08 0.075 NOAA10 24-hr D 0.07 10-Year-Current Rainfall=5.33" 0.065 Runoff Area=907 sf 0.06 Runoff Volume=199 cf 0.055 Runoff Depth=2.63"

Runoff Volume=199 cf 0.055 Runoff Depth=2.63" 0.05 Flow (cfs) 0.045 Tc=1.0 min 0.04 CN=74 0.035 0.03 0.025 0.02 0.015 0.01 0.005 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. Hydrograph for Subcatchment 3S: Proposed Pervious Time Precip. Excess Runoff Time Precip. Excess Runoff (hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs) 0.00 0.00 0.00 0.00 47.00 5.33 2.63 0.00 1.00 0.07 0.00 0.00 48.00 5.33 2.63 0.00 2.00 0.15 0.00 0.00 49.00 5.33 2.63 0.00 3.00 0.24 0.00 0.00 50.00 5.33 2.63 0.00 4.00 0.35 0.00 0.00 51.00 5.33 2.63 0.00 5.00 0.47 0.00 0.00 52.00 5.33 2.63 0.00 6.00 0.59 0.00 0.00 53.00 5.33 2.63 0.00 7.00 0.73 0.00 0.00 54.00 5.33 2.63 0.00 8.00 0.89 0.01 0.00 55.00 5.33 2.63 0.00 9.00 1.05 0.03 0.00 56.00 5.33 2.63 0.00 10.00 1.28 0.08 0.00 57.00 5.33 2.63 0.00 11.00 1.58 0.17 0.00 58.00 5.33 2.63 0.00 12.00 2.52 0.62 0.04 59.00 5.33 2.63 0.00 13.00 3.75 1.42 0.01 60.00 5.33 2.63 0.00 14.00 4.05 1.64 0.00 61.00 5.33 2.63 0.00 15.00 4.28 1.81 0.00 62.00 5.33 2.63 0.00 16.00 4.44 1.93 0.00 63.00 5.33 2.63 0.00 17.00 4.60 2.05 0.00 64.00 5.33 2.63 0.00 18.00 4.74 2.16 0.00 65.00 5.33 2.63 0.00 19.00 4.86 2.26 0.00 66.00 5.33

0 2.05 0.00 64.00 5.33 2.63 0.00 18.00 4.74 2.16 0.00 65.00 5.33 2.63 0.00 19.00 4.86 2.26 0.00 66.00 5.33 2.63 0.00 20.00 4.98 2.35 0.00 67.00 5.33 2.63 0.00 21.00 5.09 2.43 0.00 68.00 5.33 2.63 0.00 22.00 5.18 2.51 0.00 69.00 5.33 2.63 0.00 23.00 5.26 2.57 0.00 70.00 5.33 2.63 0.00 24.00 5.33 2.63 0.00 71.00 5.33 2.63 0.00 25.00 5.33 2.63 0.00 72.00 5.33 2.63 0.00 26.00 5.33 2.63 0.00 27.00 5.33 2.63 0.00 28.00 5.33 2.63 0.00 29.00 5.33 2.63 0.00 30.00 5.33 2.63 0.00 31.00 5.33 2.63 0.00 32.00 5.33 2.63 0.00 33.00 5.33 2.63 0.00 34.00 5.33 2.63 0.00 35.00 5.33 2.63 0.00 36.00 5.33 2.63 0.00 37.00 5.33 2.63 0.00 38.00 5.33 2.63 0.00 39.00 5.33 2.63 0.00 40.00 5.33 2.63 0.00 41.00 5.33 2.63 0.00 42.00 5.33 2.63 0.00 43.00 5.33 2.63 0.00 44.00 5.33 2.63 0.00 45.00 5.33 2.63 0.00 46.00 5.33 2.63 0.00