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230550 HydroCAD
Concept HydroCAD-230550 Type II 24-hr 100-yr Rainfall=8.10"
Prepared by Lane Engineering, LLC Printed 5/26/2025
HydroCAD® 10.00-17 s/n 03788 © 2016 HydroCAD Software Solutions LLC Page 21

Summary for Subcatchment 3S: P-1 (ORANGE)

Runoff = 8.15 cfs @ 11.98 hrs, Volume= 0.522 af, Depth> 6.89"

Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 0.10-24.01 hrs, dt= 0.03 hrs
Type II 24-hr 100-yr Rainfall=8.10"

Area (sf) CN Description
21,882 98 Unconnected roofs, HSG D
17,710 80 >75% Grass cover, Good, HSG D
39,592 90 Weighted Average
17,710 44.73% Pervious Area
21,882 55.27% Impervious Area
21,882 100.00% Unconnected

Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry,

Subcatchment 3S: P-1 (ORANGE)
Hydrograph

9 Runoff
8.15 cfs
8 Type II 24-hr
100-yr Rainfall=8.10"
7
Runoff Area=39,592 sf
6
Runoff Volume=0.522 af
Flow (cfs) 5 4 Runoff Depth>6.89"
Tc=6.0 min

CN=90
3

2

1

0
2 4 6 8 10 12 14 16 18 20 22 24
Time (hours)

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