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<br />meters per second (16,700 cfs) on June 13, These high inflows prompted higher than expected
<br />releases during the month of June, Releases of 311 cubic meters per second (] ] ,000 cfs) were
<br />made during much of June, However, there was no significant flooding in the city of Green
<br />River, Wyoming, located 60 river miles below the dam, The flood stage is exceeded when
<br />flows at Green River exceed 354 cubic meters per second (12,500 cfs),
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<br />Because the mean annual inflow of 1,480 MCM (1.229 MAF) far exceeds Fontenelle's storage
<br />capacity of 426 MCM (,345 MAF), significant power plant bypasses are expected under the
<br />most probable and maximum probable inflow scenarios, Additionally, there is little chance that
<br />the reservoir will not fill during water year] 998, In order to minimize spring high releases, and
<br />to maximize downstream resources and power production, the reservoir will probably be drawn
<br />down to minimum pool elevation, 1970,0 meters (6463 feet) which corresponds to a volume of
<br />115 MCM (0,093 MAF) oflive storage,
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<br />Flaming Gorge Reservoir
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<br />Like Fontenelle Reservoir, inflows into Flaming Gorge were much above normal during water
<br />year 1997, April through July unregulated inflow was 2,044 MCM (1.657 MAF) or 139 percent
<br />of normal,
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<br />In May of 1997, an April though July inflow forecast of2,220 MCM (1.800 MAF) was issued
<br />by the National Weather Service for Flaming Gorge, This high inflow forecast prompted a
<br />decision to use the bypass tubes to release water in excess of power plant capacity from Flaming
<br />Gorge, Bypass releases began on May 28, with 57 cubic meters per second (2000 cfs) being
<br />released through the two bypass tubes in addition to power plant capacity of 130 cubic meters
<br />per second (4600 cfs) for a total release of 187 cubic meters per second (6600 cfs) , However,
<br />the day after the bypass releases began, heavy precipitation occurred in the Yampa River Basin,
<br />Following these heavy rains, unusually warm temperatures became manifest in the Yampa River
<br />headwaters as well, The combination of these two circumstances caused flows on the Yampa
<br />River to increase significantly, Because of concern over flooding on the Green River near
<br />Jensen, Ut. (below the confluence of the Yampa River), bypass releases were suspended on May
<br />30, The Yampa River reached a peak flow of 575 cubic meters per second (20,300 cfs) on June
<br />4, 1997, A day later flows on the Green River at Jensen reached 708 cubic meters per second
<br />(25,000 cfs), These flows were the highest peak flows recorded since 1984,
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<br />Bypass releases were reestablished on June 16, The Yampa River had dropped substantially by
<br />this time, but inflow forecasts to Flaming Gorge showed that the additional release of water was
<br />needed, The bypass release that began on June 16, however, differed from the earlier bypass
<br />operation in that the full capacity of the bypass tubes was utilized; the total release was 243
<br />cubic meters per second (8,600 cfs), This bypass operation was scheduled to last from June 16
<br />to June 23,
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<br />On June 21, however, in the late afternoon, a failure occurred in one of the bypass tubes, This
<br />caused flooding to occur within the power plant, which then triggered a complete shut-down of
<br />the power plant itself. For about six hours crews worked to contain the damage and return stable
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<br />September 3, 1997
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