2025 02 Drainage Statement Signed

2025-01 HydroCAD NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Dynamic Engineering Printed 2/21/2025 HydroCAD® 10.20-6a s/n 08640 © 2024 HydroCAD Software Solutions LLC Page 16 2025-01 HydroCAD NOAA 24-hr D 2-Year Rainfall=3.44" Prepared by Dynamic Engineering Printed 2/21/2025 HydroCAD® 10.20-6a s/n 08640 © 2024 HydroCAD Software Solutions LLC Page 17 Summary for Subcatchment 4S: Proposed Pervious [49] Hint: To<2dt may require smaller dt Runoff = 0.37 cfs@ 12.11 hrs, Volume= 0.026 af, Depth= 1.08" Routed to Link 6L : Proposed Total 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 2-Year Rainfall=3.44" Area (sf)_CN Description 2,096 61 _>75% Grass cover, Good, HSG B 9,762 74 >75% Grass cover, Good, HSG C 833, 80 _>75% Grass cover, Good, HSG D 12,691 72 Weighted Average 12,691 100.00% Pervious Area Te Length Slope Velocity Capacity Description (min) (feet) (ft) _(ft/sec) (cfs) 34 21 0.0150 0.11 ‘Sheet Flow, Sheet Flow - AB Grass: Short n= 0.150 P2= 3.35" Sheet Flow, Sheet Flow - BC Smooth surfaces n=0.011 P2= 3.35" Shallow Concentrated Flow, SCF - CD Paved Kv= 20.3 fps of 59 0.0252 8.51 6.68 Pipe Channel, Pipe Flow - DE 12.0" Round Area= 0.8 sf Perim=3.1' r= 0.25! n= 0.011 Concrete pipe, straight & clean 0.2 111 0.0300 9.29 7.29 Pipe Channel, Pipe Flow - EF 12.0" Round Area= 0.8 sf Perim= 3.1' r=0.25' n= 0.011 Concrete pipe, straight & clean 0.1 48 0.0200 7.58 5.95 Pipe Channel, Pipe Flow - FG 12.0" Round Area= 0.8 sf Perim=3.1' r= 0.25" n= 0.011 Concrete pipe, straight & clean of 26 0.0200 7.58 + —-5.95_ Pipe Channel, Pipe Flow - GH 12.0" Round Area= 0.8 sf Perim=3.1' r= 0.25! n= 0.011 Concrete pipe, straight & clean 0.0 27 =0.0300 10.78 13.22 Pipe Channel, Pipe Flow - HI 15.0" Round Area= 1.2 sf Perim=3.9' r=0.31' n= 0.011 Concrete pipe, straight & clean 0s 43 0.0300 1.40 03 35 0.0082 1.84 44 370 Total Subcatchment 4S: Proposed Pervious Hydrograph of ose} | oe} | oaeb | ost} oat” o2e |” 026 o2ed | e224] 02] onal” ort | ond | oad orf] oon} | 064} - 0.08 02. Flow (cfs) O07 236 867 8.9 10 1 2 1a te ie 16 V7 18 18 20 OT DD 0 24 25 26 27 28 29 20 Time (hours)