Page 23 - planning-committee-packet

230550 HydroCAD
Concept HydroCAD-230550 Type II 24-hr 2-yr Rainfall=3.60"
Prepared by Lane Engineering, LLC Printed 5/26/2025
HydroCAD® 10.00-17 s/n 03788 © 2016 HydroCAD Software Solutions LLC Page 4

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

Runoff = 3.23 cfs @ 11.98 hrs, Volume= 0.196 af, Depth> 2.54"

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 2-yr Rainfall=3.60"

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
3.23 cfs
Type II 24-hr
3
2-yr Rainfall=3.60"
Runoff Area=40,379 sf
Runoff Volume=0.196 af
Flow (cfs) 2 Runoff Depth>2.54"

Tc=6.0 min
CN=90

1

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

8.13.25 PC Meeting Packet_pg. 21 of 78