Drainage Report

Basin 1 without exfiltration Proposed basin 1 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 35 Summary for Subcatchment 28S: Basin 1 [47] Hint: Peak is 754% of capacity of segment #4 Runoff = 29.62 cfs @ 12.41 hrs, Volume= 4.400 af, Depth= 7.30" Routed to Pond 29P : Basin 1 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 193,625 98 Paved parking, HSG C 121,301 74 >75% Grass cover, Good, HSG C 314,926 89 Weighted Average Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 24.0 100 0.0050 0.07 Sheet Flow, grass Grass: Dense n= 0.240 P2= 3.44" 0.6 144 0.0690 3.94 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 3.7 642 0.0206 2.91 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.9 873 0.0520 7.62 3.93 Pipe Channel, 18.0" Round w/ 12.0" inside fill Area= 0.5 sf Perim= 3.3' r= 0.16' n= 0.013 Corrugated PE, smooth interior 30.2 1,759 Total