J_2024 05 09_West Orange Stormwater Management Plan

Post Development West Orange A_03 01 12 Type III 24-hr 100 yr Rainfall=8.72" Prepared by TRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Printed 3/14/2012 Page 37 Summary for Subcatchment 1C: 1C Runoff = 1.76 cfs@ 12.08 hrs, Volume= Runoff by SCS TR-20 method, Type III 24-hr 100 yr Rainfall=8.72" UH=SCS, Split 0.136 af, Depth= 7.13" Pervious/Imperv., Time Span= 0.00-30.00 hrs, Area (sf) CN Description * 4,402 5.534 98 78 Impervious, HSG D Meadow, non-grazed, HSG D 9,936 5,534 4,402 87 78 98 Weighted Average 55.70% Pervious Area 44.30% Impervious Area Tc (min) Length (feet) Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) 0.6 50 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 1.76 Cfs ------ OB---- i —t— i— t s 5 BMB 1- aBBWj 8 Type III 24-hr 100 yr Rainfall=8.72H Runoff Area=9,936 sf Runoff Volume=0.136 af Runoff Depth=7.13" Flow Length=142' Tc=6.0 min CN=78/98 9 10 11 12 13 14 15 18 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) dt= 0.01 hrs