J_2024 05 09_West Orange Stormwater Management Plan

Post Development West Orange A_03 01 12 Type III 24-hr 10 yr Rainfall=5.21" Prepared by TRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Printed 3/14/2012 Page 21 Summary for Subcatchment 1C: 1C Runoff = 0.95 cfs @ 12.09 hrs, Volume= Runoff by SCS TR-20 method, Type III 24-hr 10 yr Rainfall=5.21" UH=SCS, Split 0.072 af, Depth= 3.81" Pervious/lmperv., Time Span= 0.00-30.00 hrs, dt= Area (sf) CN Description * 4,402 5.534 98 78 Impervious, HSG D Meadow, non-qrazed, HSG D 9,936 5,534 4,402 87 78 98 Weighted Average 55.70% Pervious Area 44.30% Impervious Area Tc Length (min) (feet) 0.6 50 Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) 0.0300 Sheet Flow, 1.46 Smooth surfaces n= 0.011 P2= 3.42" Shallow Concentrated Flow, 0.4 92 0.0666 3.87 Grassed Waterway Kv= 15.0 fps 1.0 142 Total, Increased to minimum Tc = 6.0 min Subcatchment 1C: 1C Hydrograph 0.95 Cfs ------ rjm---- Type III 24-hr 10 yr Rainfall-4.21" Runoff Area=9,936 sf Runoff Volume=0.072 af Runoff Depth=3.81" Flow Length=142' Tc=6.0 min CN=78/98 p i i ........... ............... ii 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) ml 0.01 hrs