J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (25-Year) NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" West Orange HydroCAD_Post Printed 5/13/2024 Page 27 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 13S: PO-DA K Runoff = 0.37 cfs @ 12.22 hrs, Volume= Routed to Pond 7P : O-1A 0.038 af, Depth> 4.47" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-24.00 hrs, dt= 0.0100 hrs NOAA 24-hr D 25-Year Rainfall=6.44", P2=3.42" Area (sf) 1,350 1,133 1,917 4,400 3,050 1,350 CN 98 80 73 Description Impervious, Pavement, HSG D >75% Grass cover, Good, HSG D Brush, Good, HSG D Weighted Average 69.32% Pervious Area 30.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.1 100 0.0772 0.14 Sheet Flow, Woodland Sheet Flow Woods: Light underbrush n= 0.400 P2= 3.42" 2.3 139 0.0424 1.03 Shallow Concentrated Flow, Shallow Concentrated Flow Woodland Kv= 5.0 fps 14.4 239 Total Subcatchment 13S: PO-DA K Hydrograph Runoff 0.4 0.38 0.36 0.37 cfs NOAA 24-hr D 25-Year Rainfall=6.44" P2=3.42" Runoff Area=4,400 sf Runoff Volume=0.038 af Runoff Depth>4.47" Flow Length=239' Tc=14.4 min CN=WQ Flow (cfs) 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) 15 16 17 18 19 20 21 22 23 24