8259

• UCREFRP Catalog Number: 8259
• Author: Kircher, J. E.
• Title: Sediment Transport and Source Areas of Sediment and Runoff, Big Sandy River Basin, Wyoming.
• USFW Year: 1982.
• USFW - Doc Type: Water-Resources Investigations 81-72,
• Copyright Material: NO

The hydrographs for Pacific Creek and the Big Sandy River below Eden
for water year 1968 (fig. 15) show the coincidence of the spring runoff
from Pacific Creek with the peak flow in the Big Sandy River below Eden.
The hydrographs also show a peak flow during the summer, indicating that
water was released from the Big Sandy Reservoir that year with some flow
coming from irrigation return flows. Little Sandy Creek contributes
little to the flow of the Big Sandy River because flow is diverted to the
Eden Valley Reservoir.
Streamflow data are summarized for seven gaging stations within the
basin in table 4, which shows the period of record for each gaging sta-
tion, the drainage area, the mean annual discharge, and the effects of
man on the individual streams near each gaging station. The mean annual
runoffs are variable within the basin, ranging from rates of about 1.0
cubic foot per second per square mile at station 09214000, Little Sandy
Creek near Elkhorn, to about 0.01 cubic foot per second per square mile
at station 09215000, Pacific Creek near Farson.
CHANNEL SHAPE AND SIZE
The shape of stream channels is highly organized and is similar for
rivers of the same size in comparable climatic and geologic settings.
Channel shape is a complex result of many interacting factors of which
there are two general classes: (1) Factors related to the size, lith-
ology, amount, and depositional forms of the sediment load and (2)
hydraulic factors related to water flow. The channel is formed by the
water in the channel and the sediment it carries.
The hydraulic geometry exhibits the consistent manner in which
natural stream channels are shaped to carry water and sediment load
imposed from upstream. This consistency indicates that natural channels,
self-formed and self-maintained, seek a shape and size consistent with
the sediment yield and water discharge. Alteration in this natural shape
and size will lead to erosion or deposition as the channel processes
operate toward re-establishment of quasi-equilibrium under the new condi-
tions.
Data to prepare relations of hydraulic geometry for all the
streamflow-gaging stations given in table 5 were obtained from discharge
measurements. All open-water discharge measurements for each station
were used with no biasing by elimination of data.
These data were transformed using logarithms and a two-variable
regression run to arrive at the power function of the form y = aXn and,
in this instance:
W = aQb? (1)
D = cQf, and (2)
V=kQm (3),
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