7798

• UCREFRP Catalog Number: 7798
• Author: Richardson, S.
• Title: Conceptual Management Plan for Razorback Sucker Habitat Enhancement in Flooded Bottomlands, Escalante Ranch, Jensen, Utah.
• USFW Year: 1994.
• USFW - Doc Type: \
• Copyright Material: NO

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Green River at Jensen

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1995

Figure 11. Maximum Flows (cfs) for May and June 1946 - 1993
(From Cooper and Severn 1994b)

Tremendous variability characterizes maximum flows prior to 1963,
when Flaming Gorge Dam went into operation. since that time,
peak flows have been reduced and fluctuation in flows have been
controlled. This has tremendous ramifications for larval
razorback suckers which are dependent on high flows of sufficient
duration to provide access to flooded bottom lands and other off-
channel habitats.

An estimated 40,000 cfs flow in the Green River would be required
to overtop the banks and dike which presently exist on the study
site. Even if the dike were removed, flows of 25/000 to 30,000
cfs may be necessary to overtop the banks and flood the wetland
area. This is due to incision of the river channel and bank
stabilization caused by the salt cedar invasion (FLO Engineering
1993). Flows of this magnitude have occurred only twice in the
past ten years. If, as proposed in this plan, an inlet structure
is designed to provide access to the river, flows between 12,000
and 14,000 cfs would provide flow into the wetland area of the
site (FLO Engineering 1993).

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