J_2024 05 09_West Orange Stormwater Management Plan

Type III 24-hr 2 yr Rainfall=3.42" Post Development West Orange A_03 01 12 Prepared by TRC Engineers, Inc. Printed 3/14/2012 Page 4 HvdroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Summary for Subcatchment 1B: 1B Runoff = 0.39 cfs@ 12.09 hrs, Volume= Runoff by SCS TR-20 method, Type III 24-hr 2 yr Rainfall=3.42" UH=SCS, 0.029 af, Depth= 1.80" Split Pervious/Imperv., Time Span= 0.00-30.00 hrs, dt= Area (sf) CN Description * 1,769 6,795 98 78 Impervious, HSG D Meadow, non-qrazed, HSG D 8,564 6,795 1,769 82 78 98 Weighted Average 79.34% Pervious Area 20.66% Impervious Area Tc (min) Length (feet) Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) 2.4 40 0.2500 0.28 Sheet Flow, 0.3 55 0.0360 2.85 Shallow Concentrated Flow, 2.7 95 Total, Increased to minimum Tc = 6.0 min Grass: Dense n= 0.240 P2= 3.42' Grassed Waterway Kv= 15.0 fps Subcatchment 1B: 1B Hydrograph 0.440.424 . 0.39 0 44 0.384 0.360.34-= 0.32-: _ _ - L . J__ U.J-J .i_- L_ _ 4_ L _ J___ 0.3_ 0.26-: £ 0.24-1 ■' 0.22-: 5 0.24 0.18 0.16 0.14 0.12 : Type III 24-hr 2yr i RainfaH=3,42" Runoff Area=8,564 sf Runoff Volume=0.029 af Runoff Depth=i.80" - 1— t - *1 —I— 1— r - 7 - “i— r - r —1 Flow Length=95' Tc=6.0 min : !CN=78/98 j______»___1____i_______t____ — I— i —I — 0 14 0.08- ____ L — 1 — J . . 1 --------I ------ L - J _ - 0.06 ---->-.r 7-1--------- - r —1 1 1 — - - — r —1 0.04- 0.024 01 imtmwarn 234 567 .............. 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) 7Z77 — 0.01 hrs