Drainage Report

Basin 2-5 without exfiltration Proposed Basin 2-5 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 29 Summary for Subcatchment 38S: Basin 2-5 [47] Hint: Peak is 987% of capacity of segment #2 Runoff = 11.68 cfs @ 12.17 hrs, Volume= 1.158 af, Depth= 8.42" Routed to Pond 39P : pond 2-5 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 60,317 98 Roofs, HSG C 11,558 98 Water Surface, 0% imp, HSG C 71,875 98 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.5 100 0.0100 1.08 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.44" 3.0 920 0.0410 5.17 1.18 Pipe Channel, 12.0" Round w/ 8.0" inside fill Area= 0.2 sf Perim= 2.2' r= 0.11' n= 0.013 4.5 1,020 Total, Increased to minimum Tc = 10.0 min Subcatchment 38S: Basin 2-5 Hydrograph 13 Runoff 11.68 cfs 12 11 NOAA 24-hr D 10

cfs 12 11 NOAA 24-hr D 10 100-Year Rainfall=8.66" 9 Runoff Area=71,875 sf 8 Runoff Volume=1.158 af Flow (cfs) 7 Runoff Depth=8.42" 6 Flow Length=1,020' 5 Tc=10.0 min 4 CN=98/98 3 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)