Stormwater Management Report Revised as of 01282026 4936 0314 8685 v2

24-223 DRAINAGE DESIGN-PROPOSED-UPDATE NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Prepared by Jarmel Kizel Architects & Engnrs Printed 1/28/2026 HydroCAD® 10.20-6a s/n 12607 © 2024 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment P1-P: P1 PERVIOUS Runoff = 0.12 cfs @ 12.17 hrs, Volume= 886 cf, Depth= 1.22" Routed to Link 11L : Proposed Disturbed Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-36.00 hrs, dt= 0.50 hrs NOAA 24-hr D 2-Year-2020 Rainfall=3.47", P2=3.47" Area (sf) CN Description 8,717 74 >75% Grass cover, Good, HSG C 8,717 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.1 100 0.0430 0.17 Sheet Flow, Grass: Dense n= 0.240 P2= 3.47" 0.1 44 0.0470 12.36 15.17 Pipe Channel, Yard Inlet 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.012 0.2 325 0.0450 31.77 898.40 Pipe Channel, 72" Culvert 72.0" Round Area= 28.3 sf Perim= 18.8' r= 1.50' n= 0.013 10.4 469 Total