J_2024 05 09_West Orange Stormwater Management Plan

Post Development West Orange A_03 01 12 Prepared by TRC Engineers, Inc. Type III 24-hr 2 yr Rainfall=3.42" Printed 3/14/2012 HvdroCAD® 9.10 s/n 06401 © 2009 HydroCAD Software Solutions LLC Page 10 Summary for Pond Basin2: Basin 2 Inflow Area = Inflow Outflow = Primary = Secondary = 0.721 ac, 54.26% Impervious, Inflow Depth = 1.81" for2yr 0.72 cfs @ 12.41 hrs, Volume= 0.109 af 0.58 cfs @ 12.52 hrs, Volume= 0.087 af, Atten= 20%, 0.23 cfs @ 12.52 hrs, Volume= 0.080 af 0.35 cfs @ 12.52 hrs, Volume3 0.007 af event Lag= 6.5 min Routing by Dyn-Stor-Ind method, Time Span3 0.00-30.00 hrs, dt= 0.01 hrs / 2 Peak Elev= 598.56'@ 12.52 hrs Surf.Area3 1,018 sf Storage3 1,426 cf Plug-Flow detention time3 147.5 min calculated for 0.087 af (80% of inflow) Center-of-Mass det. time3 67.9 min ( 908.5 - 840.5 ) Volume Invert Avail.Storage Storage Description #1 596.25' 4,191 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation (feet) Surf.Area (sq-ft) Inc.Store (cubic-feet) Cum. Store (cubic-feet) 596.25 597.25 598.25 599.25 600.25 319 536 878 1,335 2,565 0 428 707 1,107 1,950 0 428 1,135 2,241 4,191 Device Routing Invert Outlet Devices #1 Primary 594.00' 12.0" Round Culvert L= 78.0' Ke= 0.500 #2 #3 Device 1 Device 2 597.50' 598.00' #4 Secondary 598.50' Inlet / Outlet Invert3 594.00' / 592.00' n= 0.020 Corrugated PE, corrugated interior 3.0" Vert. Orifice C3 0.600 24.0" x 24.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads S= 0.0256 7 Cc= 10.0' long x 12.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64 Primary OutFlow Max=0.23 cfs @ 12.52 hrs HW=598.56' TW=593.19' (Dynamic Tailwater) 1=Culvert (Passes 0.23 cfs of 5.41 cfs potential flow) 2=Orifice (Orifice Controls 0.23 cfs @ 4.65 fps) 3=Grate (Passes 0.23 cfs of 10.87 cfs potential flow) Secondary OutFlow Max=0.35 cfs @ 12.52 hrs HW=598.56' TW=593.19’ (Dynamic Tailwater) 4=Broad-Crested Rectangular Weir (Weir Controls 0.35 cfs @ 0.61 fps) 0.900