02-12-2020 Workshop & Council Packets

Home Browse Search

MSE 24-hr 3 10-Year Rainfall=4.19"Proposed Conditions - Filtration Printed 12/27/2019Prepared by Larson Engineering Page 14HydroCAD® 10.00-21 s/n 01934 © 2018 HydroCAD Software Solutions LLC Summary for Subcatchment A: Runoff = 10.00 cfs @ 12.34 hrs, Volume= 36,663 cf, Depth= 2.40" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-90.00 hrs, dt= 0.01 hrs MSE 24-hr 3 10-Year Rainfall=4.19" Area (sf)CN Description * 4,845 98 Impervious 162,884 80 >75% Grass cover, Good, HSG D * 15,805 98 New Impervious 183,534 82 Weighted Average 162,884 88.75% Pervious Area 20,650 11.25% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.6 113 0.1504 0.25 Sheet Flow, Grass: Dense n= 0.240 P2= 2.75" 12.9 117 0.0427 0.15 Sheet Flow, Grass: Dense n= 0.240 P2= 2.75" 3.8 61 0.2500 0.27 Sheet Flow, Grass: Dense n= 0.240 P2= 2.75" 24.3 291 Total Summary for Subcatchment B: Runoff = 2.07 cfs @ 12.14 hrs, Volume= 4,688 cf, Depth= 3.06" Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv., Time Span= 0.00-90.00 hrs, dt= 0.01 hrs MSE 24-hr 3 10-Year Rainfall=4.19" Area (sf)CN Description * 9,000 98 New Impervious 9,393 80 >75% Grass cover, Good, HSG D 18,393 89 Weighted Average 9,393 51.07% Pervious Area 9,000 48.93% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.7 38 0.0340 0.11 Sheet Flow, Grass: Dense n= 0.240 P2= 2.75" 1.5 116 0.0200 1.31 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.75" 7.2 154 Total