7208

• UCREFRP Catalog Number: 7208
• Author: Lyons, J.
• Title: Green River Channel Characteristics Below Flaming Gorge.
• USFW Year: 1989.
• USFW - Doc Type: Denver, Co.
• Copyright Material: NO

5
The median diameter of the bed of the Green River at the Quarry site is
approximately 0.4 mm and about 1 percent of the bed is made up of clay and
silt and about 1 percent of the bed is composed of gravel. At the Ouray
Refuge, the median bed-material size is 0.25 mm with less than 1 percent of
the bed finer than sand and less than 1 percent gravel in the bed. Near
Willow Creek, the median bed material is 0.3 mm with less than 1 percent of
the bed composed of clay and silt and about 3 percent of the bed composed of
gravel. Thus, the bed-material load carried by the Green River is essen-
tially equal to its sand load. Sand load is defined as that portion of the
total sediment load coarser than 0.0625 mm (see figure 7).
Sediment Rating Curves
Using the Modified Einstein procedure (USBR [6]), the sand-load discharge was
computed for each sample collected at the three sampling locations. The com-
puted sand loads for the Dinosaur Quarry and Ouray Refuge sites are plotted in
figures 8 and 9 along with the suspended sand loads measured at the Jensen
Geological Survey gauge from 1951-1986. The data collected from 1986 to 1988
at these two sites fall within the scatter of the gauge data. Thus, a
suspended sand-load rating curve developed for the Jensen gauge was used to
describe the sand-load transport at the Quarry and Refuge sites, see figure 10.
The computed sand loads for the data collected at the site
are plotted in figure 11 along with the suspended sand-loa
Ouray Geological Survey gauge from 1951 to 1966. The data
1986-1988 fall within the scatter of the gauge data so the
rating curve developed for the Ouray gauge (figure 12) was
the sand-load transport at the site below Willow Creek.
below Willow Creek
ds measured at the
collected in
suspended sand-load
used to describe
Only eight data sets applicable to the Modified Einstein procedure were
available for the Geological Survey gauge at Green River, Utah. A suspended
sand-load rating curve was developed from the data collected from 1951 to 1982
at this gauge (figure 13).
Suspended sediment rating curves were developed for the Geological Survey
gauges on the White and Duchesne Rivers. The Duchesne is gauged near
Randlett, Utah, approximately 10 miles upstream of its confluence with the
Green. Suspended sediment data were collected by the Geological Survey at this
site from 1976 to 1987. A suspended sediment rating curve (figure 14) was deve-
loped from 106 data pairs.
The White River has been gauged since 1974 at a location near its confluence
with the Green. A suspended sand-load rating curve was developed from 42 data
pairs for which particle size analysis of the suspended sediment was available
(figure 15).
Effective Discharge
The effective discharge is an index of the range of flows that influence the
shape of a channel. It is defined as the increment of flow that occurs fre-
quently enough and carries sufficient sediment to maximize the sediment
transported by the stream. For his postreservoir period, 1966-1981, Andrews