250701_42 ERW_Stormwater Report

NOAA 24-hr D 100-Year Rainfall=8.66" 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 34 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=6.00" Flow Length=203' Tc=5.9 min CN=78 Runoff=2.01 cfs 0.151 af Subcatchment PR 1B-I: Runoff Area=36,906 sf 100.00% Impervious Runoff Depth=8.42" Flow Length=136' Tc=1.5 min CN=98 Runoff=7.71 cfs 0.594 af Subcatchment PR 1B-P: Runoff Area=77,195 sf 0.00% Impervious Runoff Depth=6.13" Flow Length=180' Tc=7.5 min CN=79 Runoff=11.55 cfs 0.905 af Reach 10R: Inflow=17.23 cfs 1.499 af Outflow=17.23 cfs 1.499 af Reach DP1-PR: Inflow=10.10 cfs 0.921 af Outflow=10.10 cfs 0.921 af Pond BASIN: Peak Elev=19.83' Storage=0.338 af Inflow=17.23 cfs 1.499 af Discarded=1.11 cfs 0.729 af Primary=8.90 cfs 0.770 af Outflow=10.01 cfs 1.499 af Total Runoff Area = 2.922 ac Runoff Volume = 1.650 af Average Runoff Depth = 6.78" 71.00% Pervious = 2.074 ac 29.00% Impervious = 0.847 ac