complete drainage report rev 9

POA-1 NOAA 24-hr D 100-Year Rainfall=8.66" 2024-05-12 HydroCad - Proposed POA 1B-1 Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 109 Summary for Subcatchment 27S: Basin 5 - Perv Runoff = 0.57 cfs @ 12.10 hrs, Volume= Routed to Pond 18P : Basin 5 1,582 cf, Depth= 5.52" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs NOAA 24-hr D 100-Year Rainfall=8.66" Area (sf) 3,440 3,440 CN 74 Description >75% Grass cover, Good, HSG C 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.6 40 0.0200 1.19 Sheet Flow, Sheet Flow (A-B) Smooth surfaces n= 0.011 P2= 3.47" 1.2 182 2.50 Direct Entry, Pipe Flow (B-C) 1.8 222 Total Sheet Flow (A-B) Subcatchment 27S: Basin 5 - Perv Pipe Flow (B-C) Subcatchment 27S: Basin 5 - Perv Hydrograph Runoff 0.6 0.57 cfs NOAA 24-hr D 100-Year Rainfall=8.66" Runoff Area=3,440 sf Runoff Volume=1,582 cf Runoff Depth=5.52" Flow Length=222' Slope=0.0200 '/' Tc=1.8 min CN=74 0.55 0.5 0.45 Flow (cfs) 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 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 Time (hours)