complete drainage report rev 9

POA-1 2024-05-12 HydroCad - Proposed POA 1B-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 71 Summary for Pond 16P: Basin 1 Inflow Area = 416,846 sf, 59.40% Impervious, Inflow Depth = 2.57" for 10-Year event Inflow = 20.44 cfs @ 12.21 hrs, Volume= 89,159 cf Outflow = 3.24 cfs @ 12.98 hrs, Volume= 72,781 cf, Atten= 84%, Lag= 45.8 min Primary = 3.24 cfs @ 12.98 hrs, Volume= 72,781 cf Routed to Link 25L : POA 1 Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Peak Elev= 544.64' @ 12.98 hrs Surf.Area= 46,729 sf Storage= 51,866 cf Plug-Flow detention time= 520.3 min calculated for 72,771 cf (82% of inflow) Center-of-Mass det. time= 439.8 min ( 1,222.3 - 782.5 ) Volume #1 Invert 543.50' Elevation (feet) 543.50 544.00 545.00 546.00 547.00 Avail.Storage 170,585 cf Surf.Area (sq-ft) 42,000 45,955 47,156 51,115 54,695 Device #1 Routing Primary Invert 546.00' #2 #3 Primary Primary 543.82' 544.40' Storage Description Custom Stage Data (Prismatic) Listed below (Recalc) Inc.Store (cubic-feet) 0 21,989 46,556 49,136 52,905 Cum.Store (cubic-feet) 0 21,989 68,544 117,680 170,585 Outlet Devices 42.0" x 48.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads 10.0" Vert. Orifice C= 0.600 Limited to weir flow at low heads 48.0" W x 8.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=3.24 cfs @ 12.98 hrs HW=544.64' (Free Discharge) 1=Grate ( Controls 0.00 cfs) 2=Orifice (Orifice Controls 1.68 cfs @ 3.09 fps) 3=Orifice/Grate (Orifice Controls 1.55 cfs @ 1.59 fps) Pond 16P: Basin 1 Grate Orifice/Grate Orifice