2022 08 Drainage Report

2022-07-28 Proposed Hydrology NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Dynamic Engineering Printed 8/5/2022 HydroCAD® 10.20-2d_ s/n 08640 © 2021 HydroCAD Software Solutions LLC 14° Summary for Pond 5P: Basin C 0.821 ac, 12.95% Impervious, Inflow Depth= 5.90" for 100-Year event = 4.62 cfs @ 12.17 hrs, Volume= 0.404 af = 1.47 cfs @ 12.46 hrs, Volume= 0.285 af, Atten= 68%, Lag= 17.3 min Primary = 1.47 cfs @ 12.46 hrs, Volume= 0.285 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= 621.26'@ 12.46 hrs Surf.Area= 3,743 sf Storage= 7,839 cf Plug-Flow detention time= 199.5 min calculated for 0.285 af (71% of inflow) Center-of-Mass det. time= 95.6 min ( 905.6 - 810.0 ) Volume Invert___Avail,Storage Storage Description ca 618.50" 8,744 of Custom Stage Data (Prismatic) Listed below (Recalc) Elevation ‘Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) __(cubic-feet) 618.50 1,966 0 0 619.00 2,285 1,063 1,063 620.00 2,892 2,589 3,651 621.00 3,560 3,226 6,877 621.50 3,907 1,867 8,744 Device Routing Invert__Qutlet Devices #1 Primary 620.50' 8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Brimary '=Orifice/Grate (Orifice Controls 1.47 cfs @ 4.20 fps) 2022-07-28 Proposed Hydrology NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Dynamic Engineering Printed 8/5/2022 Hi 40.20-2d_ sin 08640 © 2021 HydroCAD Software Solutions LLC Pond 5P: Basin C Hydrogranh Inflow Area=0.821 ac Peak Elev=621.26" Storage=7,839 cf Flow (cf) (0-2-4 6 8 WO 14 901020 22 26 26 28 30 92 36 96 39 40 42 44 40.48 50 52 54 56 $8 BO 62 64 U6 68.70 72 ‘Tae (hours) Pond 5P: Basin C Stage-Discharge cr Elevation (Foot) ° 7 Discharge (ets)