complete drainage report rev 9

POA-2 2024-05-12 HydroCad - Proposed POA 2B-1 NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Anderson Consulting Services HydroCAD® 10.20-5c s/n 06666 © 2023 HydroCAD Software Solutions LLC Printed 10/25/2024 Page 89 Summary for Pond 42P: Basin 9 Inflow Area = 26,377 sf, 66.20% Impervious, Inflow Depth = 2.61" for 2-Year event Inflow = 1.55 cfs @ 12.14 hrs, Volume= 5,745 cf Outflow = 0.61 cfs @ 12.00 hrs, Volume= 5,745 cf, Atten= 61%, Lag= 0.0 min Discarded = 0.61 cfs @ 12.00 hrs, Volume= 5,745 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 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= 562.24' @ 12.32 hrs Surf.Area= 6,534 sf Storage= 640 cf Plug-Flow detention time= 4.9 min calculated for 5,742 cf (100% of inflow) Center-of-Mass det. time= 4.9 min ( 781.7 - 776.8 ) Volume #1 Invert 562.00' Elevation (feet) 562.00 563.00 564.00 564.42 Device #1 #2 #3 Avail.Storage 6,325 cf Surf.Area (sq-ft) 6,534 6,534 6,534 6,534 Routing Primary Primary Discarded Invert 564.00' 563.00' 562.00' Storage Description Custom Stage Data (Prismatic) Listed below (Recalc) 15,812 cf Overall x 40.0% Voids Inc.Store (cubic-feet) 0 6,534 6,534 2,744 Cum.Store (cubic-feet) 0 6,534 13,068 15,812 Outlet Devices 4.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 3.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads 4.000 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.61 cfs @ 12.00 hrs HW=562.03' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.61 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=562.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 2=Orifice ( Controls 0.00 cfs) Sharp-Crested Rectangular Weir Pond 42P: Basin 9 Orifice Exfiltration