Drainage Report

Basin 3 without exfiltration proposed basin 3 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 39 Summary for Subcatchment 37S: Basin 3 pre-development Runoff = 10.09 cfs @ 12.29 hrs, Volume= 1.098 af, Depth= 5.04" 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 100-Year Rainfall=8.66" 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 11 Runoff 10.09 cfs 10 NOAA 24-hr D 9 100-Year Rainfall=8.66" 8 Runoff Area=113,998 sf 7 Runoff Volume=1.098 af Flow (cfs) 6 Runoff Depth=5.04" 5

1.098 af Flow (cfs) 6 Runoff Depth=5.04" 5 Flow Length=304' 4 Tc=19.4 min 3 CN=70/0 2 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 Time (hours)