J_2024 05 09_West Orange Stormwater Management Plan

Type III 24-hr 2 yr Rainfall=3.42" Post Development West Orange B_03 01 12 Printed 3/14/2012 Page 4 Prepared by TRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Summary for Subcatchment 5A: PO-DA 5A Runoff = 1.84 cfs@ 12.09 hrs, Volume= 0.142 af, Depth= 2.34" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/lmperv., Time Span= O.OO-30.OO hrs, dt= 0.01 hrs Type III 24-hr 2 yr Rainfall=3.42" Area (sf) CN Description 15,734 98 Impervious, HSG D 8,318 80 Grass cover, Good, HSG D 7,713 78 Meadow, non-qrazed, HSG D 88 Weighted Average 31,765 79 16,031 50.47% Pervious Area 15,734 98 49.53% Impervious Area * h Tc (min) 1.0 Length (feet) 150 Slope Velocity (ft/ft) (ft/sec) 0.0730 2.59 Capacity Description (cfs) Sheet Flow, Smooth surfaces n= 0.011 P2= 3.42" 0.5 135 0.0590 4.93 Shallow Concentrated Flow, 0.8 180 0.0330 3.69 Shallow Concentrated Flow, 0.2 34 0.0190 2.80 Shallow Concentrated Flow, 2.5 499 Total, Paved Kv= 20.3 fps Paved Kv= 20.3 fps Paved Kv= 20.3 fps Increased to minimum Tc = 6.0 min Subcatchment 5A: PO-DA 5A Hydrograph i---- !—i—i—r r - r ■ 84 cfs f r~ r - l 1 8 Type III 24-hr 2 yr RainfalN3.42" Runoff Area=31,765 sf Runoff Volume=0.142; af Runoff Depth=2.34" Flow Length=499' Tc=6.0 min CN=79/98 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Tims (hours)