102 Sams -REV 12-02-25 NOAA 24-hr D 10-Year Rainfall=5.38" Prepared by Haler Consulting Printed 04/12/2025 HydroCAD® 10.20-2h s/n 10351 © 2024 HydroCAD Software Solutions LLC Page 26
Summary for Subcatchment 143S: DA P2 (Impervious)
Runoff = 2.42 cfs @ 12.13 hrs, Volume=10,058 cf, Depth= 5.14"
Routed to Pond 149P : WQ Infiltration Basin #2
10,058 cf, Depth= 5.14"
Runoff by SCS TR-20 method, UH=Delmarva, Split Pervious/Imperv. UI as Pervious, Time Span= 0.00-72.00 hrs, dt= NOAA 24-hr D 10-Year Rainfall=5.38"
Area (sf) CN Description
23,470 98 Paved parking, HSG A
23,470 98 100.00% Impervious Area
Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs)
0.8 100 0.0500 2.05 Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42"
4.1 350 0.0050 1.44 Shallow Concentrated Flow, Paved Kv= 20.3 fps
4.9 450 Total
Subcatchment 143S: DA P2 (Impervious)