Revised Stormwater Management Report

POA 2 proposed 2024-05-12 HydroCad - Proposed POA 2 NOAA 24-hr D 10-Year Rainfall=5.22" Prepared by Anderson Consulting Services Printed 6/29/2024 Page 85 HydroCAD® 10.20-5a s/n 06666 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 21S: Basin 4 - Imp Runoff = 5.76 cfs @ 12.12 hrs, Volume= Routed to Pond 22P : Basin 4 20,787 cf, Depth= 4.98" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-80.00 hrs, dt= 0.04 hrs NOAA 24-hr D 10-Year Rainfall=5.22" Area (sf) 6,970 43,091 50,061 50,061 Tc (min) 0.9 Length (feet) 70 4.6 5.5 685 755 CN 98 98 98 Description Roofs, HSG D Paved parking, HSG C Weighted Average 100.00% Impervious Area Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) 0.0200 1.33 Sheet Flow, Sheet Flow (A-B) Smooth surfaces n= 0.011 P2= 3.47" 2.50 Direct Entry, Pipe Flow (B-C) Total Subcatchment 21S: Basin 4 - Imp Hydrograph Runoff 6 5 Flow (cfs) 4 3 2 5.76 cfs NOAA 24-hr D 10-Year Rainfall=5.22" Runoff Area=50,061 sf Runoff Volume=20,787 cf Runoff Depth=4.98" Flow Length=755' Slope=0.0200 '/' Tc=5.5 min CN=98 1 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 74 76 78 80 Time (hours)