8056

• UCREFRP Catalog Number: 8056
• Author: Hamill, J.
• Title: Restoring and Protecting Instream Flows for Endangered Fish in the Upper Colorado River Basin.
• USFW Year: 1992.
• USFW - Doc Type: Denver, CO.
• Copyright Material: NO

Program. The focus has been on three Reclamation reservoirs:
Flaming Gorge on the Green River, Blue Mesa (or the Aspinall
Units) on the Gunnison River, and Ruedi on the Frying Pan River
(Figure 2).

Ruedi Reservoir on the Frying Pan River, Colorado, is providing
flows in the late summer and early fall to enhance flows for
endangered fish in the Colorado River approximately 150 miles
downstream. Releases are being targeted at a 15-mile reach of
the Colorado River immediately upstream of the Gunnison River
that is severely impacted by irrigation diversions. The reach is
a concentration area for adult Colorado squawfish and in the
1970's and early 1980's was used regularly by razorback suckers.
In 1989, Reclamation, the Service, and the Conservation Board
entered into a 40-year agreement to provide 10,000 acre-feet of
water from Ruedi reservoir to enhance flows in the 15-mile reach
during the late summer and early fall. In 1991, the Service
requested an additional 10,000 acre-feet of water from Ruedi
Reservoir (totaling 20,000 acre-feet) because a surplus supply of
water was available in Ruedi and other efforts to acquire water
for the 15-mile reach through the Recovery Program had not
materialized. An agreement was executed between the Service,
Reclamation, and Conservation Board in 1991 and again in 1992 to
provide the additional 10,000 acre-feet. Under the agreements,
Reclamation releases water from Ruedi according to the schedule
provided by the Service, the Conservation Board and the State
Engineer protect the releases through the 15-mile reach from
diversion, and the Service evaluates the effect of the releases
on the endangered fish.

Flaming Gorge Dam in northeast Utah regulates flows in the Green
River. Since the early 1980's, studies have been conducted to
evaluate the impacts of the dam operation on the endangered fish.
The results of these studies are now being used by the Service to
develop its biological opinion on the operation of Flaming Gorge
Dam pursuant to section 7 of the Endangered Species Act. A draft
biological opinion issued in early 1992 outlined a reasonable and
prudent alternative to preclude jeopardy to the endangered fish
from the continued operation of the dam. The reasonable and
prudent alternative contained four major elements:

1. Refinement of the operation of Flaming Gorge so that flow
and temperature regimes of the Green River more closely
resemble historic conditions.

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