Stormwater Management Report Feb 2026 resubmissionrcd 2 26 2026

2026-02 Proposed Conditions - AJH NOAA 24-hr D 10-Year-Current Rainfall=5.38", P2=3.47" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 29 Summary for Pond 2P: BIO BASIN Inflow Area = 0.140 ac, 64.29% Impervious, Inflow Depth = 4.46" for 10-Year-Current event Inflow = 0.69 cfs @ 12.10 hrs, Volume= 0.052 af Outflow = 0.48 cfs @ 12.11 hrs, Volume= 0.043 af, Atten= 30%, Lag= 0.5 min Primary = 0.48 cfs @ 12.11 hrs, Volume= 0.043 af Routed to Link 2L : POI #1 Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs Peak Elev= 623.29' @ 12.11 hrs Surf.Area= 689 sf Storage= 636 cf Plug-Flow detention time= 150.3 min calculated for 0.043 af (84% of inflow) Center-of-Mass det. time= 74.8 min ( 839.5 - 764.7 ) Volume Invert Avail.Storage Storage Description #1 622.00' 1,219 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 622.00 323 0 0 623.00 577 450 450 624.00 960 769 1,219 Device Routing Invert Outlet Devices #1 Primary 619.11' 15.0" Round Culvert L= 35.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 619.11' / 618.93' S= 0.0051 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf #2 Device 1 622.86' 0.6' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #3 Device 1 623.70' 48.0" x 48.0" Horiz. Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.48 cfs @ 12.11 hrs HW=623.29' (Free Discharge) 1=Culvert (Passes 0.48 cfs of 12.55 cfs potential flow) 2=Sharp-Crested Rectangular Weir (Weir Controls 0.48 cfs @ 2.15 fps) 3=Grate ( Controls 0.00 cfs)