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Show Minimum flows would consist of spills during years of high runoff, releases for downstream rights including the fishery bypasses at Upper Stillwater and Soldier Creek Dams, seepage past diversion and impoundment structures, and inflows beginning immediately below features. For the Uinta Basin streams, significant ( greater than 500 acre- feet per year) releases for dovmstream rights would occur only on Rock Creek. This means that, except for Rock Creek, minimum flow problems for fishery purposes would occur on all streams for about 9 months of the year ( July through March). This would be because at all times other than during spring runoff the aqueduct system would be capable of diverting most of the natural stream- flow at the diversion points. Tnus, the aggregate flows during part of the year for a portion of the stream channels would be lower than the minimum flows recommended by the State of Utah, the Bureau of Sport Fisheries and Wildlife, and the Forest Service. Figures C- l through C~ 3 also show the locations of all pertinent Geological Survey streamflow gaging stations. Because of the long period of record, there are unique values that can be used to express the stream- flows that would be expected for given periods of time. These are the mean or average daily flows and the average monthly flows. When the average monthly flow shows little change in magnitude from 1 month to the next, it is an indication that there are only minor daily flow fluctuations. The streamflow extremes are best represented by records of the year that maximum runoff occurred ( maximum year) and the year that the minimum runoff occurred ( minimum year). It is important to realize that streamflows, even for daily periods, are not constant and the fluctuations near an average can be significant. Under natural conditions, flow fluctuations per unit time are at a minimum because tributary inflows are quite constant. Tables C- 5 through C- 18 present maximum, minimum, and average flow figures in an attempt to illustrate flow patterns. The terminology used in *-; te tables is defined as follows: Maximum year - The year in which the maximum runoff occurred in the drainage basin for the period of record. Minimum year - The year during a drought period in which the minimum runoff occurred in the drainage basin. |