J_2024 05 09_West Orange Stormwater Management Plan

Type III 24-hr 2 yr Rainfall=3.42" Printed 3/14/2012 Page 7 Post Development West Orange A_03 01 12 Prepared by TRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Summary for Subcatchment 3B: 3B Runoff = 0.67 cfs @ 12.09 hrs, Volume= Runoff by SCS TR-20 method, Type III 24-hr 2 yr Rainfall=3.42" UH=SCS, 0.052 af, Depth= 2.57" Split Pervious/lmperv., Area (sf) CN Description 5,785 1,111 3,792 98 98 78 Impervious, HSG D Gravel Road, HSG D Meadow, non-grazed, HSG D 10,688 3,792 6,896 91 78 98 Weighted Average 35.48% Pervious Area 64.52% Impervious Area * * Time Span= 0.00-30.00 Tc (min) Length (feet) 1.3 100 0.0150 1.27 Sheet Flow, 0.8 150 0.0400 3.00 Smooth surfaces n= 0.011 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 2.1 250 Total, hrs, dt= Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) Increased to minimum Tc = 6.0 min Subcatchment 3B: 3B Hydrograph 0 75 L .. L - L-J 0.67 0.7- L Type I’ll 24-lir 2 yr LLftairifejll=3.42n Runoff Area=10,688 sf Runoff Vblume=0.052 af Runoff PepihjF^57" -ii-L-i Flow Length=250' : r i ; Tc=6;0 min CN=78/98 0.65- 06 — t. / 0 55 0.50.45- L_1 / / r-i * 0.4- ■- 0.350.30.25- 0.2- r- r-i 0.15- rr L_ _ ___1 _ J 0.10.05- 6 7 8 - c 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