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<br />0017~(l <br /> <br />12.2 Results <br /> <br />Comparisons of flow and salt values are provided for five flow stations. <br />Results are presented in tabular and graphical forms for each of the <br />five stations. The tables include monthly values of historic flow, <br />simulated flow, and the difference between historic and simulated flow <br />expressed as a percentage of historic flow. Similar tables are provided <br />for historic and simulated salt values. <br /> <br />Four types of graphs are provided. These are (1) a time series plot of <br />historic flow and simulated flow, (2) a time series plot of the arith- <br />metic difference between historic and simulated flows, (3) a time series <br />plot of the cumulative arithmetic difference between historic and simu- <br />lated flows, and (4) a correlation diagram of historic flow plotted <br />against simulated flow. On the fourth graph, the symbol used to iden- <br />tify 1968-1982 values is a square; the symbol used to identify 1983 <br />values is a triangle. <br /> <br />Overall, simulated values are very close to the historic values. Flow <br />is generally simulated better than salt, as seen in the following sum- <br />mary table. <br /> <br />Stat ion <br /> <br />Percent difference of 16-year <br />averages (simulated - historic) <br /> <br />Flow <br /> <br />Salt <br /> <br />Colorado River near Cisco, UT <br />Green River at Green River, UT <br />Colorado River at Lees Ferry, AZ <br />Colorado River below Hoover Dam <br />Colorado River at Imperial Dam <br /> <br />0.15 <br />-1.61 <br />-0.67 <br />-1.62 <br />-4.42 <br /> <br />4.45 <br />-1. 78 <br />3.08 <br />-3.15 <br />-5.28 <br /> <br />As seen in the table, the CRSM generally yields values of flow and salt <br />that are lower than historical data, especially at the lower end of the <br />basin. The 5 percent undersimulation of salt load at Imperial Dam will <br />not change Reclamation's future TDS projections or salt load values. <br />Methods used to determine past salt-flow relationships in the Colorado <br />River Basin are presently being studied by the U.S. Geological Survey <br />in conjunction with Reclamation. <br /> <br />It was determined during the study that the results were very sensitive <br />to the magnitude of depletions and bank storage rates, especially the <br />cumulative difference graphs. In addition to this, the four graphs <br />reveal some recurring monthly patterns and general trends that suggest <br />fine tuning of some methods and data in the CRSS. Analysis of these <br />possible problem areas and modifications to the data and methods will be <br />accomplished in the future. In addition, a more complete comprehensive <br /> <br />55 <br />