Revised Stormwater Management Report

POA 2 proposed 2024-05-12 HydroCad - Proposed POA 2 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 6/29/2024 Page 217 HydroCAD® 10.20-5a s/n 06666 © 2023 HydroCAD Software Solutions LLC Summary for Pond 41P: Basin 10 Inflow Area = 97,058 sf, 61.64% Impervious, Inflow Depth = 7.35" for 100-Year event Inflow = 14.24 cfs @ 12.18 hrs, Volume= 59,478 cf Outflow = 13.47 cfs @ 12.21 hrs, Volume= 59,478 cf, Atten= 5%, Lag= 2.1 min Discarded = 2.22 cfs @ 11.64 hrs, Volume= 45,419 cf Primary = 11.25 cfs @ 12.21 hrs, Volume= 14,059 cf Routed to Link 28L : POA 2 Routing by Stor-Ind method, Time Span= 0.00-80.00 hrs, dt= 0.04 hrs Peak Elev= 576.39' @ 12.21 hrs Surf.Area= 9,583 sf Storage= 3,699 cf Plug-Flow detention time= 4.4 min calculated for 59,449 cf (100% of inflow) Center-of-Mass det. time= 4.4 min ( 772.6 - 768.2 ) Volume #1 Invert 576.00' Elevation (feet) 576.00 577.00 578.00 579.00 Avail.Storage 28,749 cf Surf.Area (sq-ft) 9,583 9,583 9,583 9,583 Device #1 Routing Primary Invert 576.15' #2 Primary 576.15' #3 Discarded 576.00' Storage Description Custom Stage Data (Prismatic) Listed below (Recalc) Inc.Store (cubic-feet) 0 9,583 9,583 9,583 Cum.Store (cubic-feet) 0 9,583 19,166 28,749 Outlet Devices 42.0" x 48.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads 42.0" x 48.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads 10.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=2.22 cfs @ 11.64 hrs HW=576.03' (Free Discharge) 3=Exfiltration (Exfiltration Controls 2.22 cfs) Primary OutFlow Max=11.05 cfs @ 12.21 hrs HW=576.38' (Free Discharge) 1=Grate (Weir Controls 5.53 cfs @ 1.58 fps) 2=Grate (Weir Controls 5.53 cfs @ 1.58 fps)