Stormwater Report

512-516 Pleasant Valley Way, West Orange 1240815-pipes NOAA 24-hr D 10-Year-2020 Rainfall=5.38", P2=3.47" Prepared by Casey & Keller, Inc Printed 8/25/2025 HydroCAD® 10.20-7a_s/n 03272 © 2025 HydroCAD Software Solutions LLC Page 16 Summary for Subcatchment 1: Exisiting Runoff = 1.63 cfs@ 12.13 hrs, Volume= 0.136 af, Depth= 4.37" 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 2,676 98 Buildings 7 794 98 Walks/Steps & Patio 7,679 98 Paved parking, HSG C 5,093 74 _>75% Grass cover, Good, HSG C 16,242 90 Weighted Average 5,093 74 31.36% Pervious Area 11,149 98 68.64% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (fft)__(fl/sec) (cfs) 41 66 0.0680 0.27 Sheet Flow, 1 Grass: Short n=0.150 P2= 3.47" 1.4 21 0.0950 0.24 Sheet Flow, 2 Grass: Short n=0.150 P2= 3.47" 0.2 13 0.0390 1.24 Sheet Flow, 3 Smooth surfaces n= 0.011 P2= 3.47" 0.1 13 0.0390 4.01 Shallow Concentrated Flow, 4 Paved Kv= 20.3 fps 0.1 28 0.0360 3.85 Shallow Concentrated Flow, 5 Paved _Kv= 20.3 fps 5.9 141 Total 23