J_2024 05 09_West Orange Stormwater Management Plan

Post Development West Orange B_03 01 12 Prepared by TRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HvdroCAD Software Solutions LLC Type III 24-hr 10 yr Rainfall=5.21" Printed 3/14/2012 Page 27 Summary for Subcatchment 9A: PO-DA 9A Runoff = 2.69 cfs @ 12.38 hrs, Volume= 0.334 af, Depth= 3.62" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/lmperv., Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type III 24-hr 10 yr Rainfall=5.21" * ★ * Area (sf) CN Description 650 98 Impervious, HSG D 1,367 98 Gravel road, HSG D 46,220 85 Yard stone, HSG D 48,237 86 Weighted Average 46,220 85 95.82% Pervious Area 2,017 98 4.18% Impervious Area Tc (min) 21.7 Length (feet) 100 2.5 Slope Velocity Capacity (ft/ft) (ft/sec) (cfs) 0.0070 0.08 Description 190 0.0060 1.25 4.3 130 0.0010 0.51 Shallow Concentrated Flow, Yard Stone Unpaved Kv= 16.1 fps Shallow Concentrated Flow, Yard Stone Unpaved Kv= 16.1 fps 28.5 420 Total Sheet Flow, Yard Stone n= 0.250 P2= 3.42" Subcatchment 9A: PO-DA 9A Hydrograph 2.69 Cfs —i—nam—— — i------ Type III 24-hr 10 yr Rainfall=5.21" Runoff Area=48,237 sf Runoff Volume=0.334 af Runoff Depth=3.62" Flow Length=420' y Tc=28.5 min CN=85/98 mmm 0 1 2 3 4 5 6 7 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) \wmw