J_2024 05 09_West Orange Stormwater Management Plan

Pre-Development West Orange with ponds 2 Type III 24-hr 2 yr Rainfall=3.42" Printed 3/4/2012 Page 10 Prepared by TRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Summary for Subcatchment 7S: EX-DA 7 Runoff = 4.25 cfs @ 12.11 hrs, Volume= Runoff by SCS TR-20 method, Type III 24-hr 2 yr Rainfall=3.42" * * * UH=SCS, 0.324 af, Depth= 1.62" Split Pervious/lmperv., Area (sf) CN Description 805 2,198 10,157 86,177 5,402 98 98 85 80 73 Impervious, HSG D Gravel road, HSG D Yard stone, HSG D >75% Grass cover, Good, HSG D Brush, Good, HSG D 104,739 101,736 3,003 81 80 98 Weighted Average 97.13% Pervious Area 2.87% Impervious Area Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) 4.5 70 0.1600 0.26 0.8 70 0.0857 1.46 Capacity (cfs) Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Description Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Woodland Kv= 5.0 fps 2.4 310 0.0200 7.7 450 Total Shallow Concentrated Flow, 2.12 Grassed Waterway Kv= 15.0 fps Subcatchment 7S: EX-DA 7 Hydrograph | ■ Runoff \ 4.25 cfs ------- CZT--- Type III 24-hr 2 yr Rainfall-3.42';' Runoff Area=104,739 sf Runoff; Vo|ume=0.324: af Runoff DepthH.82" _ i_i__j___ i__i__a___i _ Flow Length=450' Tc=7.7 mih CN=80/98 / - -I------- I----- _ _ .t i t i I t—i 01 'I'"'P ....................................... .......................... ii ipi i i p i i ifmi p ii rpi n p i i ......................................... .......................... 2 34 56 10 11 12 113 14 15 18 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours)