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. HvdroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Printed 3/14/2012 Page 36 Summary for Subcatchment 1B: 1B Runoff = 1.44 cfs@ 12.09 hrs, Volume= Runoff by SCS TR-20 method, Type III 24-hr 100 yr Rainfall=8.72" UH=SCS, Split 0.107 af, Depth= 6.56" Pervious/lmperv., Time Span= 0.00-30.00 hrs, Area (sf) CN Description * 1,769 6,795 98 78 Impervious, HSG D Meadow, non-grazed, 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 0.3 55 0.0360 2.85 2.7 95 Total, Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps Increased to minimum Tc = 6.0 min Subcatchment 1B: 1B Hydrograph —i—i—i—zi—i—i—t—r —i—i—i—i—r i i i i * • • i i i i i i ' i i i i i i i • i i i i i i i i i i 1.44 cfs : : i i i i ; i , i i i i Rainfall-8.72" : Runoff Area-8,564 sf Runoff Volume=0.107; af Runoff Depth=6.S6" Flow Length=95' Tc=6.0 min CN=78/98 1- f I 12 34 6 78 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