J_2024 05 09_West Orange Stormwater Management Plan

Pre-Development West Orange with ponds 2 Type III 24-hr 10 yr Rainfall=5.21" Prepared byTRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Printed 3/4/2012 Page 24 Summary for Subcatchment 1S: EX-DA 1 4.66 cfs @ 12.24 hrs, Volume= Runoff Runoff by SCS TR-20 method, Type III 24-hr 10 yr Rainfall=5.21" UH=SCS, Split 0.486 af, Depth= 3.20" Pervious/Imperv., Time Span= 0.00-30.00 hrs, 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 Sheet Flow, 1.3 270 0.0520 3.42 Shallow Concentrated Flow, 18.2 420 Total Grass: Dense n= 0.240 P2= 3.42" Grassed Waterway Kv= 15.0 fps Subcatchment 1S: EX-DA 1 Hydrograph L _ J _ J t___ L _ J ________ __ I ___ X - J________ - L _ J ____________ * _ - _1_I___!_1 _!_______ I_____I_____ L 66 cfs ;Type;lll 24-hr 10;yr Rainfall^S^I'!'’ Rundff Area-79,301: sf R uhoff; Vol;ume=0.486; af ; Runoff bepth=3.20':' Flow Length-420' Tc;=18L2; niirt I :CN=78/98 3- 0 \mm 1 2 |*ll II ft II l|*ll ll'|t II H 34 56 78 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) dt= 0.01 hrs