9609

• UCREFRP Catalog Number: 9609
• Author: U.S. Bureau of Reclamation.
• Title: Ruedi Reservoir 2012 Agreement Final Environmental Assessment Fryingpan-Arkansas Project.
• USFW Year: 2002.
• USFW - Doc Type: Loveland, CO.
• Copyright Material: NO

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Ruedi 2012 Agreement Final EA Page 3-9
Both brown and rainbow trout use similar redds (gravel beds) for spawning, but beyond this have
significantly different reproductive cycles as shown in Table 3.4.
Table 3.4. Approximate Time and Duration of Spawning, and the Critical Early
Development Life Stages for Brown and Rainbow Trout in the Fryingpan River Below
Ruedi Dam.
ADULT
SPECIES SPAWNING EGG
INCUBATION EGG
HATCHING FRY
EMERGENCE
Brown trout 10/15-11/15 10/15-5/1 4/1-6/1 5/15-6/15
Rainbow trout 4/1-5/1 4/1-6/15 6/1-7/1 6/15-7/15
(Nehring and Anderson, 1993)
3.2.2 Threatened and Endangered Species
The Colorado River basin upstream of Lake Powell is home to 14 native fish species, four of
which are now endangered. These four fish - the Colorado pikeminnow, razorback sucker,
bonytail and humpback chub - evolved in the Colorado River basin and exist nowhere else on
earth.
Critical habitat for two of the four endangered fish, the Colorado pikeminnow and razorback
sucker, occurs within the 15 Mile Reach and upstream to Rifle, Colorado, an area affected by the
Proposed Action. The fish use backwaters and side channels along this stretch of the Colorado
River to reproduce, feed and grow. In recent times, multiple factors have contributed to the loss
of habitat and decline of these native species. One contributor, loss of stream flows in the 15
Mile Reach, caused by depletions in the watershed upstream of 15 Mile Reach directly impacts
sustainability of the two species. Insufficient flows limit both the quantity and quality of the
habitat for the Colorado pikeminnow and razorback sucker, and directly affect key reproductive
life stages. The existing depletions in the Upper Colorado River Basin above the confluence
with the Gunnison River are estimated at approximately 1 million of/year (USDI, 1999)
There are currently two contracts that make Ruedi Reservoir water available for the 15 Mile
Reach to benefit endangered fish. The first, executed in 1990, is a forty-year contract with the
CWCB for 10,000 of of water for the 15 Mile Reach. The contract stipulates that 5,000 of will
be made available annually, and an additional 5,000 of will be made available at least 4 out of 5
years through re-regulation. The second contract is a short-term (one-year) agreement with the
CWCB and the Service to make 10,825 of of water available to the 15 Mile Reach. This short-
term agreement would be replaced by the agreement identified in the proposed action of this
Environmental Assessment.
There are several other contracts and agreements associated with other reservoirs that directly
and indirectly enhance endangered fish habitat in the 15 Mile Reach, such as the Municipal
Recreation Agreement among Reclamation and the municipalities of Grand Junction, Palisade
and Fruita, and the west and east slope Water Users' Agreements to make 10,825 of available for
the 15 Mile Reach. These contracts deliver water from a variety of water sources including
Green Mountain, Wolford Mountain, and Williams Fork Reservoirs.