Stormwater Management Report Feb 2026 resubmissionrcd 2 26 2026

2026-02 Proposed Conditions - AJHNOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Prepared by Dynamic Engineering Printed 2/16/2026 HydroCAD® 10.20-7a s/n 08640 © 2025 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment 4S: PDA #1 - Undetained Impervious Runoff = 0.87 cfs @ 12.10 hrs, Volume= 0.065 af, Depth= 3.85" Routed to Link 2L : POI #1 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.001 hrs NOAA 24-hr D 2-Year-Projected Rainfall=4.09", P2=4.09" Area (sf) CN Description 8,866 98 Paved parking, HSG D 8,866 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.0 93 0.0188 1.50 Sheet Flow, A-B Smooth surfaces n= 0.011 P2= 4.09" 1.0 326 0.0115 5.64 6.93 Pipe Channel, B-C 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.013 Corrugated PE, smooth interior 2.0 419 Total Subcatchment 4S: PDA #1 - Undetained Impervious Hydrograph 0.95 Runoff 0.87 cfs 0.9 0.85 NOAA 24-hr D 0.8 2-Year-Projected Rainfall=4.09" 0.75 P2=4.09" 0.7 0.65 Runoff Area=8,866 sf 0.6 Runoff Volume=0.065 af Flow (cfs)

Runoff Area=8,866 sf 0.6 Runoff Volume=0.065 af Flow (cfs) 0.55 Runoff Depth=3.85" 0.5 0.45 Flow Length=419' 0.4 Tc=2.0 min 0.35 CN=98 0.3 0.25 0.2 0.15 0.1 0.05 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours)