J_2024 05 09_West Orange Stormwater Management Plan

Post Development West Orange B_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 41 Summary for Subcatchment 4: PO-DA 4 Runoff = 5.85 cfs @ 12.15 hrs, Volume= 0.515 af, Depth= 6.74" 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 100 yr Rainfall=8.72" Area (sf) CN Description 4,334 Impervious, HSG D 98 5,398 98 Gravel road, HSG D 14,366 80 Grass cover, Good, HSG D 15.808 Meadow, non-qrazed, HSG D 78 84 39,906 Weighted Average 30,174 75.61% Pervious Area 79 24.39% Impervious Area 9,732 98 * ★ ★ Tc (min) 9.6 Length (feet) 100 Slope Velocity Capacity (ft/ft) (ft/sec) 0.0500 0.17 0.5 120 0.0830 4.32 0.7 145 0.0480 3.29 10.8 365 Total Description (cfs) Sheet Flow, Grass: Dense n= 0.240 P2= 3.42" Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps Subcatchment 4: PO-DA 4 Hydrograph | ffl Runofffr 5.8 5 cfs Type III 24-hr 100 yr r Rainfall=8.72" Runoff Area=39,906 sf Runoff Volume=0.515 af Runoff Depth=6.74" Flow Length-365' Tc=10.8 min CN=79/98 T “ o 3 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)