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<br />, \. <br /> <br />The relationship between flow and backwater number was not as clear <br />as that for backwater area. However, optimum flows for production <br />of backwaters were notable. At the Island Park site the optimum <br />flows for backwater numbers were 1,381 and 1,101 cfs. The optimum <br />flow at the Jensen was 1,687 cfs, although an optimum range of <br />flows from 1,773 to 1,101 cfs was indicated. <br /> <br />The optimum flnw at the Ouray site was 1,381 cfs, and an optimum <br />range of 1,687 to 1,381 cfs was indicated. The Sand Wash site was <br />unique in that backwater numbers were maximized at 5,260 cfs. <br />Backwater numbers from 2,423 to 1,101 cfs were very similar. <br /> <br />The optimum flow for backwater numbers at the Mineral Bottom site <br />was 3,261 cfs, the same flow that maximized backwater area. <br /> <br />The optimum flows for backwater numbers for the combined four upper <br />sites were 1,381 and 1,687. The optimum range for backwater <br />numbers was from 1,773 to 1,101 cfs. <br /> <br />Recommendations <br /> <br />Based on the finaings of the 1987 study, future studies should <br />focus on two areas. Fluctuating flows should be tested to see how <br />normal dam operations effect backwater development. The 1987 study <br />was accomplished by using Flaming Gorge Dam releases to mimic a <br />natural hydrograph for the Green River and collecting aerial <br />photography as flows were steadily dropped from May through August. <br />The pilot study of 1986 indicated that periods of high flows and <br />fluctuating flows will significantly alter backwaters and sandbar <br />development. Therefor, data collection for future studies (1988) <br />should include the following components: operation of the dam for <br />one week of normal operating fluctuations (800 cfs - 2,600 cfs <br />daily) followed by a week of steady flows at 1,500 cfs. Aerial <br />photography will be acquired during the week of steady flows. This <br />operation should be repeated to produce two sets of aerial <br />photography for backwater habitat mapping at 1,500 cfs. A flow of <br />approximately 1,500 cfs should be chosen because it is well within <br />the range of 1,101 to 1,773 cfs indicated by the 1987 data. <br />Immediately following this scenario, operations should fluctuate <br />from 800 cfs - 4,200 cfs daily. This scenario will test backwater <br />habitat formation at the proposed upgrade, or maximum power <br />generation. Again a week of 1,500 cfs steady flows will be <br />obtained to aquire the final set of aerial photographs. These flow <br />scenarios will help determine if normal dam operations will effect <br />backwater formation differently than the "natural" hydrograph used <br />for the 1987 study. It was determined that this study should be <br />evaluated at the Ouray study site because of it's relative <br />importance to the Colorado squawfish. This research will relate <br />