8188

• UCREFRP Catalog Number: 8188
• Author: Muth, R. T., et al.
• Title: Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Forge Dam.
• USFW Year: 2000.
• USFW - Doc Type: \
• Copyright Material: NO

Final Report

3-51

September 2000

Table 3. 14.-Flows to maintain in-channel and floodplain processes relevant to the life-history
needs of endangered fishes within three reaches of the Green River downstream of Flaming
Gorge Dam.

Flow Condition by Reacha
Process Reach 1 Reach 2 Reach 3
In-Channel Processes
Establish low-velocity Not applicable because Sand-bar topography, and therefore the availability of
habitats (e.g., backwaters) of life history of fishes low-velocity habitats, changes annually in response to
during base-flow period. in reach. the passage of peak flows. As a result, no single base
flow maximizes habitat availability under all
conditions, and the range of measured optimal base
flows varied from 35 to 140 m3/s in the years studied.
Large floods rebuild sand-bar topography and result in
habitat availability being maximized at higher flows.
Subsequent 10w-flood-peak years reduce the flow at
which habitat availability is maximized. The duration
of floods that are less than bankfull but greater than
bar top should be minimized.
Maintain levels of flow Not applicable because Prior to dam Not determined, but
variability during the base- of life history of fishes construction, median presumed similar to
flow period comparable to in reach. coefficient of variation Reach 2.
those that occurred prior to in base flows within a
dam construction. year was about 41 % in
summer and autumn and
about 28% in winter.
Between-day differences
were about 3% pre-dam.
Maintain in-channel 244 m3/s caused some Flows that produce Flows that produce
habitats (redistribute sand channel widening in incipient motion of incipient motion of
deposits, prevent vegetation Lodore Canyon and particles on existing particles on existing
establishment on deposits significant redistribu- deposits have been deposits have been
and channel narrowing). tion of sand. calculated as 2235 m3/s calculated as 2208 m3/s
in the Ouray area. in Canyonlands National
Park.
Maintain clean spawning Flows 2244 m3/s could Sedimentation of Near the head of Gray
substrates. provide suitable spawning bar at RK 504 Canyon, sediments
substrates for potential occurs at flows flushed at flows between
Colorado pikeminnow >340 m3/s; subsequent 79 and 227 m3/s.
spawning in Lodore flows <200 m3/s flush
Canyon; Colorado sediment.
pikeminnow do not
currently spawn in
Lodore Canyon.