Analysis - Proposed Conditions NOAA 24-hr D 2 YR-F Rainfall=4.04" Prepared by Civil Core Consulting Printed 12/19/2025 HydroCAD® 10.20-8a s/n 13637 © 2025 HydroCAD Software Solutions LLC Page 132
Summary for Pond 33P: INFILTRATION BASIN 2
Inflow Area =27,007 sf,30.65% Impervious,Inflow Depth > 1.18"for 2 YR-F event
Inflow =0.19 cfs @12.40 hrs,Volume= 2,652 cf
Outflow =0.09 cfs @14.27 hrs,Volume= 2,652 cfAtten= 54%, Lag= 112.4 min
Discarded =0.09 cfs @14.27 hrs,Volume= 2,652 cf
Primary =0.00 cfs @0.00 hrs,Volume= 0 cf
Routed to Link 33L : POA 2
Routing by Dyn-Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 92.28' @ 14.27 hrs Surf.Area= 777 sf Storage= 408 cf
Plug-Flow detention time=36.2 min calculated for 2,652 cf (100% of inflow) Center-of-Mass det. time=36.2 min (902.5 - 866.3)
VolumeInvertAvail.StorageStorage Description
#191.65'4,378 cfCustom Stage Data (Prismatic)Listed below (Recalc)
Elevation (feet)Surf.Area (sq-ft)Inc.Store (cubic-feet)Cum.Store (cubic-feet)
91.6552000
92.00651205205
93.001,0948731,077
94.001,6291,3622,439
95.002,2491,9394,378
DeviceRoutingInvertOutlet Devices
#1Device 393.65'2.5" Vert. Orifice C= 0.600 Limited to weir flow at low heads
#2Device 394.70'48.0" x 48.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads
#3Primary93.65'12.0" Round Culvert L= 17.0' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 93.65' / 93.50' S= 0.0088 ' /' Cc= 0.900 n= 0.012 Concrete pipe, finished, Flow Area= 0.79 sf
#4Discarded91.65'4.950 in/hr Exfiltration over Surface area Phase-In= 0.01'
Discarded OutFlow Max=0.09 cfs @ 14.27 hrs HW=92.28' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.09 cfs)
Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=91.65' TW=0.00' (Dynamic Tailwater) 3=Culvert ( Controls 0.00 cfs) 1=Orifice ( Controls 0.00 cfs) 2=Grate ( Controls 0.00 cfs)
Pond 33P: INFILTRATION BASIN 2 Grate Curvient
Exfiltration