complete drainage report rev 9

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 10-Year Rainfall=5.22" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 117 Summary for Subcatchment 21S: Basin 4 - Imp Runoff = 4.78 cfs @ 12.12 hrs, Volume= Routed to Pond 22P : Basin 4 17,242 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) 29,022 12,502 41,524 41,524 CN 98 98 98 Description Roofs, HSG D Paved parking, HSG C Weighted Average 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.9 70 0.0200 1.33 Sheet Flow, Sheet Flow (A-B) Smooth surfaces n= 0.011 P2= 3.47" 4.6 685 2.50 Direct Entry, Pipe Flow (B-C) 5.5 755 Total Sheet Flow (A-B) Pipe Flow (B-C) Subcatchment 21S: Basin 4 - Imp Subcatchment 21S: Basin 4 - Imp Hydrograph Runoff 5 Flow (cfs) 4 3 2 1 4.78 cfs NOAA 24-hr D 10-Year Rainfall=5.22" Runoff Area=41,524 sf Runoff Volume=17,242 cf Runoff Depth=4.98" Flow Length=755' Slope=0.0200 '/' Tc=5.5 min 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 74 76 78 80 Time (hours)