Stormwater Report

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 24 Summary for Pond 5: Pipes Inflow Area = 0.360 ac, 72.63% Impervious, Inflow Depth= 2.24" for 10-Year-2020 event Inflow = 0.91 cfs@ 12.06 hrs, Volume= 0.067 af Outflow = 0.69 cfs @ 12.11 hrs, Volume= 0.067 af, Atten= 24%, Lag= 2.8 min Discarded = 0.03 cfs@ 9.75hrs, Volume= 0.033 af Primary = 0.66 cfs @ 12.11 hrs, Volume= 0.034 af Routed to Link 7 : Proposed Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 412.74' @ 12.11 hrs Surf.Area= 400 sf Storage= 268 cf Plug-Flow detention time= 15.3 min calculated for 0.067 af (100% of inflow) Center-of-Mass det. time= 15.3 min ( 785.8 - 770.4 ) Volume Invert Avail.Storage Storage Description #1 411.50° 329 cf 10.00'W x 40.00'L x 3.00'H Prismatoid 1,200 cf Overall - 377 cf Embedded = 823 cf x 40.0% Voids #2 412.00° 377 cf 24.0" Round Pipe Storage x 3 Inside #1 L=40.0' S= 0.0020 '/ 706 cf Total Available Storage Device Routing Invert_ Outlet Devices #1 =~ Discarded 411.50' 2.900 in/hr Exfiltration over Surface area #2 ~~~ Primary 412.00' 12.0" Round Culvert L=14.0' Ke= 0.100 Inlet / Outlet Invert= 412.00'/ 411.94" S= 0.0043 '" Cc= 0.900 n= 0.012 Corrugated PP, smooth interior, Flow Area= 0.79 sf #3 =~ Device 2 412.00’ 6.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads #4 ~=Device 2 414.00’ 24.0" x 24.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads liscarded OutFlow Max=0.03 cfs @ 9.75 hrs HW=411.53' (Free Discharge) 41=Exfiltration (Exfiltration Controls 0.03 cfs) Primary OutFlow Max=0.65 cfs @ 12.11 hrs HW=412.72' (Free Discharge) Fs-oni (Passes 0.65 cfs of 1.43 cfs potential flow) Orifice (Orifice Controls 0.65 cfs @ 3.32 fps) =Grate ( Controls 0.00 cfs) 31