J_2024 05 09_West Orange Stormwater Management Plan

Pre-Development West Orange with ponds 2 NJ DEP 2-hr NJDEP Rainfall=1.25" Prepared by TRC Engineers, Inc. Printed 3/4/2012 HvdroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Page 72 Summary for Subcatchment 6S: EX-DA 6 Runoff = 1.69 c f s @ 1.28 hrs, Volume= Runoff by SCS TR-20 method, NJ DEP 2-hr NJDEP Rainfall=1.25" * * * * UH=SCS, Split 0.078 af, Depth= 0.28" Pervious/Imperv., Area (sf) CN Description 9,501 8,481 43,082 57,041 27.592 98 98 85 80 73 Paved road, HSG D Gravel road, HSG D Yard stone, HSG D Grass cover, Good, HSG D Brush, Good, HSG D 145,697 127,715 17,982 82 80 98 Weighted Average 87.66% Pervious Area 12.34% Impervious Area Tc Length (min) (feet) Time Span= 0.00-30.00 Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) 13.2 150 0.0500 0.19 Sheet Flow, 0.1 30 0.0880 4.45 Shallow Concentrated Flow, 0.2 40 0.3130 2.80 Grass: Dense n= 0.240 P2= 3.42" Grassed Waterway Kv= 15.0 fps Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.2 30 0.0330 2.92 Shallow Concentrated Flow, 3.2 240 0.0060 1.25 Shallow Concentrated Flow, Yard Stone Unpaved Kv= 16.1 fps Unoaved Kv= 16.1 fps 16.9 490 Total hrs, dt= 0.01 hrs