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The results of the HEC -2 hydraulic models were imported into SAM and used to describe <br />a set of hydraulic parameters for sediment transport calculations. This was accomplished by <br />specifying a portion of each sub -reach as representative of the hydraulic conditions and <br />calculating average values for velocity, depth, width, and energy slope for each discharge value. <br />These parameters were then used, along with bed material particle distribution information, to <br />generate sediment transport rating curves for the sub - reaches. The "Bent's Fort°' particle <br />distribution from the geomorphological assessment completed in 1997, discussed in 3.1 <br />GEOMORPOLOGICAL ASSESSMENT, was used for the bed material parameters. This <br />particle distribution closely matched the "Highway 207" distribution, located 30 miles upstream, <br />from the same report suggesting uniform bed material throughout the reach. The Brownlie <br />sediment transport equation was used to calculate transport. This equation was used because the <br />Stable Channel geometries are calculated with this equation, thus preserving theoretical <br />consistency. The Brownlie sediment transport equation would not necessarily be the first choice <br />for transport calculation, but it is applicable to sand -bed rivers such as the Lower Arkansas. <br />Three groups of conditions were analyzed. The reach- averages from each problem area <br />were used to indicate current conditions. Because of the length of Problem Area 1, it was broken <br />into 4 parts. The sediment transport rates for this condition are listed in Table 3.5. The second <br />condition analyzed used only the HEC -2 cross - sections with a capacity of at least 1,000 cfs. The <br />results are shown in Table 3.6. <br />m_Lt_ Is r n_.:.. «: «,.­A.___+ +, a"Onnrt rnfae (rparh Averaged hvdraulic varameters). <br />I dult; <br />Discharge <br />0.0. .GAia Lill <br />Problem <br />Area 3 <br />OV)VILiilVUl. LLt". <br />Problem <br />Area 2 <br />v ."-. ...... <br />Prob. Area <br />1, pan 1 <br />__ -. - -_. - - - <br />Prob, Area <br />1, part 2 <br />Prob. Area <br />1, art 3 <br />Prob. Area <br />1, part 4 <br />(cfs). <br />(t/d) <br />(t/d) <br />Wd) <br />(t <br />(t/d) <br />(t <br />100 <br />2.35 <br />1.38 <br />0.41 <br />4.53 <br />2.52 <br />4.81 <br />200 <br />16.66 <br />13.23 <br />7.25 <br />26.58 <br />17.20 <br />29.14 <br />300 <br />43.93 <br />37.93 <br />23.49 <br />64.30 <br />43.OS <br />71.59 <br />500 <br />131.32 <br />119.00 <br />79.57. <br />163.13 <br />113.52 <br />206.64 <br />750 <br />293.11 <br />264.82 <br />184.90 <br />321.62 <br />229.28 <br />433:28 <br />1,000 <br />510.75 <br />445.83 <br />1 327.46 <br />500.01 <br />394.78 <br />1 720.64 <br />3 I h 1 d'ment trans ort rates at least 1000 cfs ca acit <br />Table <br />Discharge <br />.d. n -c CUM <br />Problem <br />se x <br />Problem <br />Prob. Area <br />Prob. Area <br />Prob. Area <br />Prob. Area <br />Area 3 <br />Area 2 <br />1, part 1 <br />1, part 2 <br />1, part 3 <br />1, art 4 <br />(cfs) <br />(t/d) <br />(t/d) <br />(t/d) <br />(t/d) <br />(t/d) <br />(t/d) <br />100 <br />4.31 <br />10.91 <br />5.13 <br />9.24 <br />44.37 <br />15.16 <br />200 <br />27.91 <br />57.73 <br />20.81. <br />48.26 <br />166.04 <br />69.38 <br />300 <br />74.07 <br />137.22 <br />45.95: <br />113.61 <br />356.00 <br />156.09 <br />500 <br />232.66 <br />360.24 <br />128.99 <br />315,07 <br />960.48 <br />400.71 <br />750 <br />557.81 <br />746.22 <br />331.43 <br />694.00 <br />1,62$.24 <br />818.97 <br />1,000 <br />1,028.76 <br />1,218.29 <br />603.32 <br />1,4$1.66 <br />3,611.55 <br />1,406.84 <br />32 <br />11 <br />J <br />C <br />r <br />