Drainage Report

Basin 2-1 Proposed Basin 2-1 R5 NOAA 24-hr D 100-Year Rainfall=8.66" Prepared by Anderson Consulting Services Printed 10/29/2023 HydroCAD® 10.20-3f s/n 06666 © 2023 HydroCAD Software Solutions LLC Page 23 Summary for Pond 41P: Pond 2-1 Inflow Area = 0.599 ac, Inflow Depth = 5.81" for 100-Year event Inflow = 3.38 cfs @ 12.17 hrs, Volume= 0.290 af Outflow = 2.50 cfs @ 12.26 hrs, Volume= 0.246 af, Atten= 26%, Lag= 5.5 min Primary = 2.50 cfs @ 12.26 hrs, Volume= 0.246 af Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Peak Elev= 547.85' @ 12.26 hrs Surf.Area= 2,020 sf Storage= 3,730 cf Plug-Flow detention time= 142.0 min calculated for 0.246 af (85% of inflow) Center-of-Mass det. time= 72.1 min ( 889.9 - 817.8 ) Volume Invert Avail.Storage Storage Description #1 546.00' 4,040 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 546.00 2,020 0 0 548.00 2,020 4,040 4,040 Device Routing Invert Outlet Devices #1 Primary 546.95' 8.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #2 Primary 547.20' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.48 cfs @ 12.26 hrs HW=547.84' (Free Discharge) 1=Orifice/Grate (Orifice Controls 1.25 cfs @ 3.59 fps) 2=Orifice/Grate (Orifice Controls 1.22 cfs @ 2.72 fps)