2022 08 Drainage Report

2022-07-28 Proposed Hydrology NOAA 24-hr D 10-Year Rainfall=5.22" Prepared by Dynamic Engineering Printed 8/5/2022 HydroCAD® 10.20-24 s/n 08640 © 2021 HydroCAD Software Solutions LLC Summary for Pond 6P: Basin D Inflow Area = 0.422 ac, 13.06% Impervious, Inflow Depth = 2.86" for 10-Year event Inflow = = 4.15 cfs@ 12.18 hrs, Volume= 0.101 af Outflow = 0.03 cfs @ 17.93 hrs, Volume= 0.019 af, Atten= 97%, Lag= 345.2 min Primary = 0.03 cfs @ 17.93 hrs, Volume= 0.019 af Routed to Link 2L : Mt. Pleasant Ave. Routing by Stor-ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 616.53’ @ 17.93 hrs Surf.Area= 2,853 sf Storage= 3,655 cf Plug-Flow detention time= 601.9 min calculated for 0.019 af (18% of inflow) Center-of-Mass det, time= 401.0 min ( 1,228.4 - 827.4 ) Volume. Invert__Avail Storage _Storage Description 1 615.00' 8,561 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf Area Inc.Store Cum.Store (feet) (sa-ft) (cubic-feet) (cubic-feet) 615.00 1,951 0 0 616.00 2,519 2,235 2,235 617.00 3,150 2,835 5,070 618.00 3,833 3,492 8,561 Device Routing invert _Outlet Devices #1 Primary 616.50' 8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Rrimary j=Orifice/Grate (Weir Controls 0.03 ofs @ 0.55 fps) 2022-07-28 Proposed Hydrology NOAA 24-hr D 10-Year Rainfall=5.22" Prepared by Dynamic Engineering HydroCAD® 10.20-2d s/n 08640 © 2021 HydroCAD Software Solutions LLC. Pe Pond 6P: Basin D Hydrograph Inflow Area=0.422 ac Peak Elev=616.53" Storage=3,655 cf g 3 é Dee a 8 8 1012 4010 IO IL D4 25 282090 31 309840 4244 40 40 99 2 54509000 62640860 7072 Time (hour) Pond 6P: Basin D Stage-Diacharge a (eee) om Elevation (Feat) 6