1240815StormWaterManagementReport

PLEASANT VALLEY WAY 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 9/12/2025 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Subcatchment 6: Bypass Runoff = 0.04 cfs @ 12.13 hrs, Volume= 0.003 af, Depth= 2.67" Routed to Link 7 : Proposed Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv. UI as Pervious, Time Span= 0.00-72.00 hrs, dt= 0.05 NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Area (sf) CN Description 605 74 >75% Grass cover, Good, HSG C 605 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.9 100 0.0650 0.28 Sheet Flow, 1 Grass: Short n= 0.150 P2= 3.47" 0.1 28 0.0900 4.50 Shallow Concentrated Flow, 2 Grassed Waterway Kv= 15.0 fps 6.0 128 Total Subcatchment 6: Bypass Hydrograph 0.046 0.044 0.04 cfs Runoff 0.042 0.04 NOAA 24-hr D 0.038 0.036 10-Year-2020 Rainfall=5.38" 0.034 0.032 P2=3.47" 0.03 0.028 Runoff Area=605 sf

P2=3.47" 0.03 0.028 Runoff Area=605 sf Runoff Volume=0.003 af Flow (cfs) 0.026 0.024 0.022 Runoff Depth=2.67" 0.02 0.018 Flow Length=128' 0.016 0.014 Tc=6.0 min 0.012 CN=74/0 0.01 0.008 0.006 0.004 0.002 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) 33