J_2024 05 09_West Orange Stormwater Management Plan

Post-Developed (O-1B) NOAA 24-hr D 2-Year_Current Rainfall=3.45", P2=3.45" West Orange HydroCAD_Post Printed 5/13/2024 Page 53 Prepared by Burns & McDonnell HydroCAD® 10.20-4b s/n 08510 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 9S: PO-DA G Runoff = 0.59 cfs @ 12.33 hrs, Volume= Routed to Pond 3P : BR-03 0.073 af, Depth> 2.26" 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 2-Year_Current Rainfall=3.45", P2=3.45" Area (sf) 4,879 2,788 9,235 16,902 12,023 4,879 * CN 98 80 85 Description Impervious, Pavement, HSG D >75% Grass cover, Good, HSG D Yard Stone/Gravel Pad, HSG D Weighted Average 71.13% Pervious Area 28.87% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 22.6 100 0.0010 0.07 Sheet Flow, Gravel Sheet Flow n= 0.100 P2= 3.45" 0.7 75 0.0121 1.77 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 23.3 175 Total Subcatchment 9S: PO-DA G Hydrograph 0.65 Runoff 0.59 cfs 0.6 NOAA 24-hr D 2-Year_Current Rainfall=3.45" P2=3.45" Runoff Area=16,902 sf Runoff Volume=0.073 af Runoff Depth>2.26" Flow Length=175' Tc=23.3 min CN=WQ 0.55 0.5 0.45 Flow (cfs) 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 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