Laserfiche WebLink
<br />LAG = 0.13 firs. (from TR-55, Figure 3.3 far a slope <br />of 1.8% and a length of 400 ft.) <br />Time of Concentration 1.667 x LAG = 0.217 hrs. <br />From TR55, Figure 5.2 for TC = 0.217 hrs., and area = <br />0.011 sq. mi. <br />Peak discharge, 10 yr., 24 hr. event = 2.2 cfs <br />Peak discharge, 25 hr., 24 hr. event = 3.8 cfs <br />The two years sediment yield is determined by applying <br />the Universal soil loss equation (A=RKLSCP) to 5.5 acres <br />of disturbed area at the laydown area where: <br />A = soil loss per unit area (tonsJacreJyr). <br />R = The rain fall factor: is the number of erosion- <br />index units in a normal year's rain. <br />• K = The sail erodibility factor: is the erosion rate <br />per unit of erosion index for a specific sail in <br />cultivated continuous fallow, on a 9 percent <br />slope T2.6 feet long. <br />L = The slope-length factor: is the ratio of soil <br />loss from the field slope length to that from a <br />72.6 foot length on the same soil type and <br />gradient. <br />S The slope-gradient factor: is the ratio of soil <br />lass from the field gradient to that from a 9 <br />percent slope. <br />C The croppino-management factor: is the ratio of <br />soil loss from a field with specified cropping <br />and management to that from the fallow condition <br />on which the factor K is evaluated. <br /> <br />D-6 <br />