complete drainage report rev 9

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 10-Year Rainfall=5.22" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 169 Summary for Pond 22P: Basin 4 Inflow Area = 49,050 sf, 84.66% Impervious, Inflow Depth = 4.61" for 10-Year event Inflow = 5.30 cfs @ 12.12 hrs, Volume= 18,836 cf Outflow = 1.23 cfs @ 12.40 hrs, Volume= 18,836 cf, Atten= 77%, Lag= 16.7 min Discarded = 1.13 cfs @ 11.80 hrs, Volume= 18,660 cf Primary = 0.10 cfs @ 12.40 hrs, Volume= 176 cf Routed to Pond 27P : Basin 2 Routing by Stor-Ind method, Time Span= 0.00-80.00 hrs, dt= 0.04 hrs Peak Elev= 572.69' @ 12.40 hrs Surf.Area= 12,197 sf Storage= 3,380 cf Plug-Flow detention time= 14.4 min calculated for 18,826 cf (100% of inflow) Center-of-Mass det. time= 14.4 min ( 770.6 - 756.3 ) Volume #1 Invert 572.00' Elevation (feet) 572.00 573.00 574.00 574.91 Device #1 #2 #3 Avail.Storage 14,197 cf Surf.Area (sq-ft) 12,197 12,197 12,197 12,197 Routing Primary Primary Discarded Invert 574.00' 572.50' 572.00' Storage Description Custom Stage Data (Prismatic) Listed below 35,493 cf Overall x 40.0% Voids Inc.Store (cubic-feet) 0 12,197 12,197 11,099 Cum.Store (cubic-feet) 0 12,197 24,394 35,493 Outlet Devices 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 6.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads 4.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=1.13 cfs @ 11.80 hrs HW=572.03' (Free Discharge) 3=Exfiltration (Exfiltration Controls 1.13 cfs) Primary OutFlow Max=0.10 cfs @ 12.40 hrs HW=572.69' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=Orifice (Orifice Controls 0.10 cfs @ 1.49 fps) Pond 22P: Basin 4 Sharp-Crested Rectangular Weir Orifice Exfiltration