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The length-slope factor for the RUSLE subroutine is as follows: <br />m <br />LS=-^(slope jaclor) <br />72.6 <br />Where: .l =Representative slope length (ft) <br />m = 0.6 for slope > ]0% <br />m = 0.5 for 4 % < slope s 10% <br />m = 0.4 for slope = 4 % <br />m = 0.3 for slope < 4% <br />The slope factor is a stepwise linear relationship with the slope breakpoint at 8% as shown on <br />figure 5.5, Slope Factor for the RUSLE, contained in the SEDCAD Users Manual (Warner and <br />Schwab, 1992). <br />The sediment graph is then routed to a structure using an exponential decay procedure <br />incorporating deposition of a particle size distribution. <br />Inputs for the sedimentology portion of the SEDCAD routine are: <br />• Particle size distribution <br />• Run off volume <br />• Peak discharge <br />• Soil erodibility factor <br />• Representative slope length <br />• Average slope <br />• Control practice factor <br />• Sediment specific weight <br />Particle Size Distribution <br />The particle size distribution used for the sedimentation analysis was previously determined for <br />TR-60 (HGCC, 1991). <br />Ruuoff Volume, V <br />The runoff volume is calculated by the SEDCAD computer model during the hydrologic modeling <br />routine. <br />Peak Discharge, QP <br />The peak discharge is calculated by the SEDCAD computer model during the hydrologic modeling <br />routine. <br />c:~87Thgg~primar}~ureU~od.how 7/16/96 <br />5 <br />