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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 22

Summary for Subcatchment 4S: P-2 (PURPLE)

Runoff = 8.31 cfs @ 11.98 hrs, Volume= 0.532 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
21,557 98 Paved parking, HSG D
18,822 80 >75% Grass cover, Good, HSG D
40,379 90 Weighted Average
18,822 46.61% Pervious Area
21,557 53.39% Impervious Area

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

Subcatchment 4S: P-2 (PURPLE)

Hydrograph
Runoff
9
8.31 cfs
Type II 24-hr
8
100-yr Rainfall=8.10"
7
Runoff Area=40,379 sf
6
Runoff Volume=0.532 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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