JMA02P003 262 270 Main Street Development Stormwater Management Report

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