2026-02 Existing and Proposed NOAA 24-hr D 10-Year-Current Rainfall=5.38" Prepared by Dynamic Engineering Printed 2/10/2026 HydroCAD® 10.20-8a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 55
Summary for Subcatchment 7S: Ex. Study Area Road (Perv)
Runoff = 0.01 cfs @ 12.93 hrs, Volume= 0.003 af, Depth= 0.28" Routed to Link 8L : Existing Study Area Road (Total)
Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year-Current Rainfall=5.38"
Area (ac)CNDescription
0.12039>75% Grass cover, Good, HSG A
0.12039100.00% Pervious Area
Tc (min)Length (feet)Slope (ft/ft) Velocity (ft/sec) Capacity (cfs)
1.0610.0100 1.06
Sheet Flow, A-B
Smooth surfacesn= 0.011 P2= 4.04"
1.0 61 Total, Increased to minimum Tc = 10.0 min
Subcatchment 7S: Ex. Study Area Road (Perv)
2026-02 Existing and ProposedNOAA 24-hr D10-Year-CurrentRainfall=5.38''
Prepared by Dynamic EngineeringPrinted2/10/2026
HydroCAD\circledR 10.20-8a s/n 08640© 2025 HydroCAD Software Solutions LLCPage 56
Summary for Subcatchment 10S: Study Area WQ MTD A-110 (Imp)
Runoff = 2.05 cfs @ 12.19 hrs, Volume= 0.261 af, Depth= 5.14" Routed to Link 10L : Study Area Study Area WQ MTD A-110 (Total)
Runoff by SCS TR-20 method, UH=Delmarva, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year-Current Rainfall=5.38"
Area (ac) CN Description
0.610 98 Paved parking, HSG A
0.610 98 100.00% Impervious Area
Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description
0.6 55 0.0302 1.62 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 4.04"
1.3 297 0.0035 3.68 4.52 Pipe Channel, B-C 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.011 Concrete pipe, straight & clean
1.9 352 Total Increased to minimum Tc = 10.0 min
1.9 352 Total, Increased to minimum Tc = 10.0 min
Subcatchment 10S: Study Area WQ MTD A-110 (Imp)