250701_42 ERW_Stormwater Report

NOAA 24-hr D 10-Year Rainfall=5.22" 250624_42 ERW Waymaker Prepared by Colliers Engineering & Design HydroCAD® 10.20-5c s/n 04431 © 2023 HydroCAD Software Solutions LLC Printed 7/1/2025 Page 16 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 PR 1A-P: Runoff Area=13,167 sf 0.00% Impervious Runoff Depth=2.90" Flow Length=203' Tc=5.9 min CN=78 Runoff=1.00 cfs 0.073 af Subcatchment PR 1B-I: Runoff Area=36,906 sf 100.00% Impervious Runoff Depth=4.98" Flow Length=136' Tc=1.5 min CN=98 Runoff=4.63 cfs 0.352 af Subcatchment PR 1B-P: Runoff Area=77,195 sf 0.00% Impervious Runoff Depth=2.99" Flow Length=180' Tc=7.5 min CN=79 Runoff=5.79 cfs 0.442 af Reach 10R: Inflow=9.28 cfs 0.794 af Outflow=9.28 cfs 0.794 af Reach DP1-PR: Inflow=3.96 cfs 0.367 af Outflow=3.96 cfs 0.367 af Pond BASIN: Peak Elev=17.57' Storage=0.194 af Inflow=9.28 cfs 0.794 af Discarded=0.74 cfs 0.500 af Primary=3.33 cfs 0.294 af Outflow=4.07 cfs 0.794 af Total Runoff Area = 2.922 ac Runoff Volume = 0.867 af Average Runoff Depth = 3.56" 71.00% Pervious = 2.074 ac 29.00% Impervious = 0.847 ac