9631

• UCREFRP Catalog Number: 9631
• Author: U.S. Bureau of Reclamation.
• Title: Operation of Flaming Gorge Dam Draft Environmental Impact Statement Executive Summary.
• USFW Year: 2004.
• USFW - Doc Type: Salt Lake City, UT.
• Copyright Material: NO

Under normal operations, reservoir releases through Flaming Gorge Powerplant range
from 800 to 4,600 cfs. These flows adhere to the interim operating criteria for Flaming
Gorge Dam established by Reclamation in September 1974. Under these criteria,
Reclamation agreed to provide (1) a minimum flow of 400 cfs at all times, (2) flows of
800 cfs under normal conditions and for the foreseeable future, and (3) flows exceeding
800 cfs when compatible with other CRSP reservoir operations.
Temperature requirements under the No Action Alternative, specified in the Reasonable
and Prudent Alternative of the 1992 Biological Opinion (p. 30), include the following:
Releases from Flaming Gorge beginning July 1 and continuing until November 1
should be of the warmest water available, approaching 59 degrees F (15 degrees C)
(highest lake levels). By releasing the warmest water available during this period,
water temperatures in the upper Green River should not differ more than 9 degrees
F (5 degrees C) in the Yampa River at Echo Park and should average near 72-
77 degrees F (22-25 degrees C) in Gray Canyon from July 1 to August 15.
S.11.1.3.2 Action Alternative - Under the Action Alternative, releases from Flaming
Gorge Dam would be patterned so that the peak flows, durations, and base flows and
temperatures, described in the 2000 Flow and Temperature Recommendations for
Reaches 1, 2, and 3 of the Green River, would be achieved.
? Reach 1 begins at Flaming Gorge Dam and extends 65 river miles to the confluence
of the Green and Yampa Rivers. In this reach, the Green River meanders about
10 river miles into northwestern Colorado and then flows southward for about
30 river miles. This reach is almost entirely regulated by releases from Flaming
Gorge Dam.
? Reach 2 begins at the confluence of the Green and Yampa Rivers in Colorado and
extends 99 river miles southwest to the White River confluence near Ouray, Uintah
County, Utah. In this reach, tributary flows from the Yampa River combine with
releases from Flaming Gorge Dam to provide a less regulated flow regime than in
Reach 1.
? Reach 3 begins at the confluence of the Green and White Rivers and extends
246 river miles south to the confluence of the Green and Colorado Rivers in
Canyonlands National Park at the boundary of Wayne and San Juan Counties in
southeastern Utah. In this reach, the Green River is further influenced by tributary
flows from the White, Duchesne, Price, and San Rafael Rivers.
Table S-1 shows a summary of the recommended spring peak and summer-to-winter base
flows from the 2000 Flow and Temperature Recommendations report for all three reaches
of the Green River. Under the Action Alternative, Flaming Gorge Dam would be
operated with the goal of achieving the 2000 Flow and Temperature Recommendations
while maintaining and continuing all authorized purposes of Flaming Gorge Dam and
Reservoir.
The 2000 Flow and Temperature Recommendations for each reach are not integrated in
such a way that a particular release from Flaming Gorge Dam could equally achieve the
recommendations for all reaches simultaneously. The intent of the Action Alternative is
first to meet the 2000 Flow and Temperature Recommendations for Reach 2 and then, if
S-16 A.- Operation of Flaming Gorge Dam Draft EIS