WSP12329

• File Number: 822.600.10
• Description: Colorado River Annual Operating Plan - Annual Reports
• Basin: Colorado Mainstem
• Date: 1/1/1995
• Author: USDOI/BOR
• Title: Annual Operating Plan
• Water Supply Pro - Doc Type: Annual Report

most probable and maximum probable inflow scenarios. Additionally, there is little chance
that the reservoir wi1l not fi1l during water year 1995. In order to minimize spring high
releases and to maximize downstream fishery resources and power production. the reservoir
wi1l probably be drawn down to minimum pool elevation 1970.0 m (6463 feet)<2) which
corresponds to a volume of 111 MCM (.090 MAF) of live storage.

To meet the above stated operational objectives, a constant release of approxima~ely 31.2 to
34.0 m3/s (1,100 to 1,200 cfs) wi1l be made through the fall and winter months, Releases at
this level wi1l provide an appropriate level of reservoir drawdown for the 1995 runoff
season, while ensuring that downstream water rights and municipal and industrial needs are
met. Under all three inflow assumptions, the reservoir is expected to fi1l in the summer of
~~. .

Flaming Gorge Reservoir

Water year 1994 unregulated inflow into Flaming Gorge Reservoir is expected to be
888 MCM (0.720 MAF) or 42 percent of average. The April through July runoff was
498 MCM (0.404 MAF) or 34 percent of the long term average. With this very low inflow,
Flaming Gorge is expected to lose approximately 661 MCM (0.536 MAF) of storage in
water year 1994.

In 1994, Flaming Gorge was operated in accordance with the Final Draft Biological Opinion
on the Operation of Flaming Gorge (FDBOFG), issued in November 1992. The FDBOFG
outlines the reservoir operations during the spring, summer, and early fall months which may
provide an improved habitat for endangered endemic species of fish. To accommodate the
FDBOFG. releases of 121.8 m3/s (4,300 cfs) were released from Flaming Gorge for four
weeks from mid-May to mid-June to coincide with the peak flow of the Yampa River. These
releases met the research objectives of a sustained flow at Jensen. Utah. of between 283 and
340 m3/s (10,000 and 12,000 cfs). After completion of the runoff, flows between 38.2 and
51.0 m3/s (1,350 and 1,800 cfs) were maintained at the Green River near Jensen. Utah.

In 1995, Flaming Gorge wi1l again be operated in accordance with the FDBOFG. If water
year 1995 runoff is similar to the probable minimum, most probable, or probable maximum
inflow scenarios; then high spring releases for one to two weeks, two to four weeks, or in
excess of six weeks duration wi1l be made, respectively. Under all inflow scenarios, low
stable flows between 31.2 and 51.0 m3/s (1,100 and 1,800 cfs) wi1l be maintained on the
Green River near the Jensen, Utah, gaging station during the summer and fall months by
adjusting Flaming Gorge releases.
J2(v t1 H~
Water year 19Wwi1l be the fffilfth year of the five year study called for in the FDBOFG to
further determine the flow needs of the endangered fish during the spring and winter months.

(2) units of length used in this document are meters (m), followed by equivalent feet
(feet)

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