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TIME OF CONCENTRATION <br />PERVI��US AREAS <br />Sheet Flow (AppiJcable to Tc only) <br />Surface Description <br />Manning's Roughness Coef�icient. nsheet <br />Flow Leng?h IL<=300'), Lsheet <br />2-Year, 24-Hour Rainfall, P2 <br />Land Slope, S�heet <br />Tt Sf�eet <br />Tt Sheet <br />Shallow Concentrated Flow (See DOE <br />Surface Description <br />Flow Length, Lshallow <br />Watercourse Slope, So <br />Time of Concentration Velocity Factor, k <br />Average Velocity, Vshallow = k x So^0.5 <br />T! Shallow <br />Tt Shallow <br />SWM <br />Channel Flow (See DOE SWM Manusl, I <br />Type of Channel <br />Flow Length, Lchannel <br />Watercou�se Slope, So <br />Time of Concentration Velocity Factor, kc <br />Average Velocity, Vchannel = k x So^0.5 <br />Tt Channel <br />Tt Channel <br />Results: Wetershed or Su6area Tc or Tt <br />Total Tc or Tt <br />Total Tc or Tt <br />111•1•1 <br />— --------�- <br />0.578 hours <br />34.659 min <br />Note: <br />1 Worksheet based on time equations irom Stormwater Management Manual for the <br />Puget Sound Basin, Chapter III <br />237 feet <br />1.55 inches <br />0.0840 fUft <br />0.58 hours <br />34.66 min. <br />Man�ewoodDetCalc rls % B/8/2(107 <br />