J_2024 05 09_West Orange Stormwater Management Plan

Pre-Development West Orange with ponds 2 Prepared by TRC Engineers, Inc. NJ DEP 2-hr NJDEP Rainfall=1.25" Printed 3/4/2012 HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Page 67 Summary for Subcatchment 1S: EX-DA 1 Runoff = 0.83 cfs @ 1.29 hrs, Volume= Runoff by SCS TR-20 method, NJ DEP 2-hr NJDEP Rainfall=1.25" UH=SCS, Split 0.041 af, Depth= 0.27" Pervious/lmperv., Time Span= 0.00-30.00 hrs, dt= Area (sf) CN Description * # 11,158 661 53,293 14,189 98 98 79 73 Paved road, HSG D Gravel road, HSG D Woods/grass comb., Good, HSG D Brush, Good, HSG D 79,301 67,482 11,819 81 78 98 Weighted Average 85.10% Pervious Area 14.90% Impervious Area Tc (min) Length (feet) Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) 16.9 150 0.0270 0.15 1.3 270 0.0520 3.42 18.2 420 Total Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps Subcatchment 1S: EX-DA 1 Hydrograph 1 0.83 - 4 ---------I ------ _ Jl i I __ L _ J___ I___ 0.8 _J . . L . J . J _______ 0 75 L .. J __ ' __ L . . J __ ' __ 0I __ J 0 I • 4 - -I _ J. - 4- - 4 - • I - - A - 4 - . x.-----1- _ L _ J _l 1 __ J __ I l i L-i • 1 ____ J ____ t L _ J 0 650.6- 0 550.55 0.45- 0.40.350.30.25-_ 4 -------I _ . 1 . - I -X _ NJ DEP 2-hr NJDEP Rainfall=1.25” Runoff Area=79,301 sf Runoff Volume=0.041 af Runoff Depth=0.277 Flow Length=420' Tc=18.2 min - 4 -------1 _ _ 0.20.15 ____I ____ J . J . 0.1- __L _ 4 .. j _ j — J - J. 0.05 o7 I -----I ------4 - 4 - - - I ____U . 1 ---J ______ 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) 0.01 hrs