WSP01172

• File Number: 822.600.10
• Description: Colorado River Annual Operating Plan - Annual Reports
• Basin: Colorado Mainstem
• Date: 1/1/1997
• Author: USDOI/BOR
• Title: Annual Operating Plan
• Water Supply Pro - Doc Type: Annual Report

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that the reservoir will not fill during water year 1997. In order to minimize spring high
releases and to maximize downstream fishery resources and power production, the reservoir
will probably be drawn down to minimum pool elevation 1970.0 meters (6463 feet) which
corresponds to a volume of 115 MCM (.093 MAP) of live storage.

To meet the above-stated operational objectives, a constant release of approximately 31.2 to
34.0 cubic meters per second (ems) [or 1,100 to 1,200 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 1997 runoff season, while ensuring that downstream
water rights and municipal and industrial needs are met.

Flaming Gorge Reservoir

Water year 1996 unregulated inflow into Flaming Gorge Reservoir was 2,166 MCM
(1.76 MAP) or 103 percent of average. The April through July runoffwas
1,578 MCM (1.28 MAF) or 100 percent of the long tenn average. With this inflow, Flaming
Gorge lost approximately 128 MCM (.104 MAF) of storage in water year 1996.

In 1996, Flaming Gorge was operated in accordance with the Biological Opinion on the
Operation of Flaming Gorge (BOFG), issued in November 1992. The BOFG outlines the
reservoir operations during the spring, summer, and early fall months which may provide an
improved habitat for endangered endemic species offish. In accord with the BOFG,
maximum powerplant releases were made from Flaming Gorge during May and June. The
goal of the release in 1996 was to maintain releases from the dam at 125 ems (4,400 cfs)
during the peak of the spring runoff of the Yampa River. Flows of the Green River at
Jensen, Utah, were expected to be between 510 ems to 623 ems (18,000 to 22,000 cfs).
Jensen is below the confluence of the Green and Yampa Rivers, and flows from the Yampa
River alone in 1996 actually exceeded 507 ems (17,900 cfs), producing flows at Jensen of
631 ems (22,300 cfs).

In water year 1997 high spring releases are again expected at Flaming Gorge. Under all
inflow scenarios, low stable flows between 31.2 and 51.0 ems (1,100 and 1,800 cfs) will
most likely be maintained on the Green River near the Jensen, Utah, gaging station during
the summer and fall months by adjusting Flaming Gorge releases. A revised biological
opinion is expected to be issued to the Bureau of Reclamation and Western Area Power
Administration in 1997. This revised opinion is scheduled to describe specific constraints
during the spring and winter seasons, but may also refine the constraints for the entire year.

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