Drainage Report

Basin 2-5 2yr w/ exfiltration Proposed Basin 2-5 R5 infil NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 2 Summary for Pond 39P: pond 2-5 Inflow Area = 1.650 ac, Inflow Depth = 3.21" for 2-Year event Inflow = 4.60 cfs @ 12.17 hrs, Volume= 0.441 af Outflow = 0.17 cfs @ 15.57 hrs, Volume= 0.441 af, Atten= 96%, Lag= 203.9 min Discarded = 0.17 cfs @ 15.57 hrs, Volume= 0.441 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 541.46' @ 15.57 hrs Surf.Area= 11,558 sf Storage= 11,150 cf Plug-Flow detention time= 654.2 min calculated for 0.441 af (100% of inflow) Center-of-Mass det. time= 654.7 min ( 1,415.1 - 760.4 ) Volume Invert Avail.Storage Storage Description #1 540.50' 40,453 cf 540 (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 540.50 11,558 0 0 544.00 11,558 40,453 40,453 Device Routing Invert Outlet Devices #1 Discarded 540.50' 0.450 in/hr Exfiltration over Horizontal area Conductivity to Groundwater Elevation = 538.00' #2 Primary 541.50' 6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.17 cfs @ 15.57 hrs HW=541.46' (Free Discharge) 1=Exfiltration ( Controls 0.17 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=540.50' (Free Discharge) 2=Orifice/Grate ( Controls 0.00 cfs)