Drainage Report

Basin 3 without exfiltration proposed basin 3 R5 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment 37S: Basin 3 pre-development Runoff = 1.79 cfs @ 12.31 hrs, Volume= 0.212 af, Depth= 0.97" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.44" Area (sf) CN Description 113,998 70 Woods, Good, HSG C Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.7 100 0.0400 0.11 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 3.44" 3.7 204 0.0340 0.92 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 19.4 304 Total Subcatchment 37S: Basin 3 pre-development Hydrograph 2 Runoff 1.79 cfs NOAA 24-hr D 2-Year Rainfall=3.44" Runoff Area=113,998 sf Runoff Volume=0.212 af Flow (cfs) 1 Runoff Depth=0.97"

12 af Flow (cfs) 1 Runoff Depth=0.97" Flow Length=304' Tc=19.4 min CN=70/0 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)