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 Prepared by TRC Engineers, Inc. HydroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Printed 3/14/2012 Page 3 Summary for Subcatchment 4: PO-DA 4 Runoff = 1.66 cfs@ 12.15 hrs, Volume= 0.146 af, Depth= 1.91" 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 2 yr Rainfall=3.42” Area (sf) 4,334 5,398 14,366 15,808 39,906 30,174 9,732 * * * CN 98 98 80 78 84 79 98 Description Impervious, HSG D Gravel road, HSG D Grass cover, Good, HSG D Meadow, non-grazed, HSG D Weighted Average 75.61% Pervious Area 24.39% Impervious Area Tc (min) 9.6 Length (feet) 100 0.5 120 0.0830 4.32 0.7 145 0.0480 3.29 Slope Velocity Capacity (ft/ft) (ft/sec) (cfs) 0.0500 0.17 Description 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 10.8 365 Total Subcatchment 4: PO-DA 4 Hydrograph 1.66 cfs Type III 24-hr 2 yr Rainfall=3.42" Runoff Area=39,906 sf Runoff Volume-0.146 af Runoff Depth=1.91" Flow Length=365' Tc=10.8 min CN=79/98 T ~ l □1 0- 4 8 ................ I' "M'l 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours)