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I I I I I I I I I I I I I I I I I I I 6 The following paragraphs discuss the operation of each of the reservoirs with respect to compact, decree, statutory, water delivery obligations, and instream flow needs for maintaining or improving aquatic resources, where appropriate. Fontenelle Reservoir AjJril through July runoff into the reservoir during water year 1992 was only 255,000 acre- feet (AF) or 29 percent of average. This is approximately the same runoff that was experienced in 1977, the previous record low runoff year. Even though releases were made at near minimum levels commencing in April 1992, and remained at this level through the remainder of water year 1992, Fontenelle was approximately 20 feet short of filling in 1992. Because the mean annual inflow of 1.2 MAF far exceeds the storage capacity of 345,000 AF, there is little chance that the reservoir will not fill during water year 1993. In order to minimize high spring releases and to maximize downstream fishery resources and power production, the reservoir will probably be drawn down to minimum pool elevation (6463.5 feet) which corresponds to a volume of 93,000 AF of live storage. To meet the previously stated operational objectives, a constant release of approximately 500 to 600 cubic feet per second (cfs) will be made through the fall and winter months. Releases at this level will provide an appropriate level of reservoir drawdown for the 1993 runoff season, while ensuring that downstream water rights and municipal and industrial needs are met. The reservoir is expected to fill in' the summer of 1993 under all three inflow scenarios. Flaming Gorge Reservoir Water year 1992 inflow into Flaming Gorge Reservoir is expected to be only 740,000 AF or 45 percent of average and the April through July runoff was only 343,000 AF (only 60,000 AF more than the record low runoff of 1977). With this low level of inflow, Flaming Gorge is expected to lose approximately 270,000 AF of storage in water year 1992. A Final Draft Biological Opinion (FDBO) from FWS on the operation of Flaming Gorge Reservoir was issued in February of 1992. The FDBO outlined how the reservoir should be operated during the spring, summer, and early fall months in order to provide better habitat for endangered endemic species of fish. In addition, it requires 5 years of additional studies to determine the flow needs of the endangered fish during the spring and winter months. In 1992, Flaming Gorge was operated in accordance with the draft biological opinion by making a 4,200 cfs release for 1 week in May and .by maintaining a flow of between 1,350 and 1,800 cfs at the Green River near Jensen, Utah, gaging station after the completion of the runoff season. In water year 1993, Flaming Gorge will be operated according to the FDBO. This operation will include high spring releases to coincide with the peak flow of the Yampa River and low