9612

• UCREFRP Catalog Number: 9612
• Author: N.A.
• Title: Flaming Gorge Flow Recommendation Investigation FG-1 Technical Integration and Final Report - Hydrology and Physical Science Chapter - Draft.
• USFW Year: 1998.
• USFW - Doc Type: \
• Copyright Material: NO

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DRAFT February 25, 1998
H. Channel Flow and Habitat
A. Annotated Abstracts - Flaming Gorge 5-Year Research Studies
The 1992 Biological Opinion established a reasonable and prudent alternative for operating
Flaming Gorge Dam to assist in recovery of the endangered fishes. Included in this reasonable
and prudent alternative was further examination after a five-year research program (which began
in 1992) for additional refinement of flows for the endangered fishes. The research summarized in
these abstracts has been conducted to provide a basis for refinement of operations at Flaming
Gorge by describing details of channel morphology and hydrology data that are important
considerations in describing habitat.
Allred, T. M. 1997. Channel Narrowing of the Green River near Green River, Utah;
History, Rates and Processes of Narrowing. M.S. Thesis, Utah State University,
Department of Geography and Earth Resources, Logan, Utah. 115 p.
Previous scientific research has documented channel narrowing on the Green River near
Green River, Utah, but the exact timing, rates, and causal mechanisms of that narrowing
have been the source of disagreement in the scientific literature. This paper demonstrates
• that the Green River has narrowed in two separate periods during the last 100 years. The
narrowing is driven primarily by changes in the hydrologic regime and not by the invasion
of saltcedar. The channel narrowed between 1930 and 1938, when a shift from wetter
than normal conditions to a period of draught led to a reduction in river discharge.
Channel vadth then remained relatively stable until construction of Flaming Gorge Dam in
1962, despite the presence of saltcedar. Narrowing has occurred since dam construction.
Detailed analysis of the formation of an inset floodplain deposit indicates that it formed by
a process of vertical accretion, during incremental events. Inset bank deposits within the
study area are composed primarily of particles smaller than 0.125 mm. Measurement of
suspended sand distribution within the water column shows that particles of this size are
carried in suspension by the 2-yr flood. Continued vertical accretion over time elevated
the floodplain surface until inundation rarely occurs.
Bell, A. 1997. Green River Flooded Bottomlands and Backwater Habitat Mapping.
Technical Memorandum No. 8260-97-01. U.S. Bureau of Reclamation, Technical Service
Center, Denver, Colorado. 7p.
Color infared 1:24,000 scale aerial photography was collected over the Green river on
Both May 18 and May 20, 1996. On May 18 the Green River near Jensen gage recorded
a daily mean discharge of 20,000 ft /s. On May 20 the daily mean discharge mesured at
• Jensen was over 22,000 W/s. Both dates of aerial photography were interpreted to
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