2025 02 Drainage Statement Signed

2025-01 HydroCAD NOAA 24-hr D 10-Year Rainfall=5.22" Prepared by Dynamic Engineering Printed 2/21/2025 HydroCAD® 10.20-6a s/n 08640 © 2024 HydroCAD Software Solutions LLC Page 24 2025-01 HydroCAD Prepared by Dynamic Engineering HydroCAD® 10.20-6a s/n 08640 © 2024 HydroCAD Software Solutions LLC NOAA 24-hr D 10-Year Rainfall=5.22" Printed 2/21/2025 Page 25 Summary for Subcatchment 1S: Existing Impervious [49] Hint: To<2dt may require smaller dt [47] Hint: Peak is 940% of capacity of segment #4 Runoff = 447 cis @ 12.10 hrs, Volume= Routed to Link SL : Existing Total 0.363 af, Depth= 4.98" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.22" Area (sf) CN Description 38,060 98 Unconnected pavement, HSG B 38,060 100.00% Impervious Area 38,060 100.00% Unconnected Te Length Slope Velocity Capacity Description (min) (feet) (ft) _(flsec) (cfs) 3.0 27 0.0700 (0.15 Sheet Flow, Sheet Flow - AB Grass: Dense n= 0.240 P2= 3.35" 07 73 0.0410 1.76 Sheet Flow, Sheet Flow - BC ‘Smooth surfaces n= 0.011 P2=3.35" 04 96 0.0470 4.40 Shallow Concentrated Flow, SCF - CD Paved Kv= 20.3 fps 02 50 0.0370 5.45 0.48 Pipe Channel, Pipe Flow - DE 4.0" Round Area= 0.1 sf Perim= 1.0° r= 0.08" n= 0.010 PVC, smooth interior 0.0 21 0.1380 19.40 10.58 Pipe Channel, Pipe Flow - EF 10.0" Round Area= 0.5 sf Perim= 2.6" r= 0.21' N= 0.010 PVC, smooth interior 43 267 Total Subcatchment 1S: Existing Impervious Hydrograph : NOAA 24-hr D ‘ 0-Year Rainfall=5 3 O12 34 6 6 7 8 8 10 i 2 1 te 1 We 17 W019 20 21 22 20 24 25 26 27 28 20 20 Time (hours)