7087

• UCREFRP Catalog Number: 7087
• Author: Elliot, J. G., J. E. Kircher and P. V. Guerard.
• Title: Sediment Transport in the Lower Yampa River, Northwestern Colorado.
• USFW Year: 1984.
• USFW - Doc Type: Denver, CO.
• Copyright Material: NO

Table 3.--Sediment-transport equations derived from sediment discharges
measured at station 09260050 Yampa River at Deerlodge Park
[Qs, sediment discharge in tans per day; Q, water discharge in cubic feet per
second; R2, coefficient of determination; SE, standard error of
estimate in percent; n, sample size; mm, millimeter]
Type of sediment
discharge Regression equation R2 SE n
Total----------------------- Q = 0.290 Qz.2s
s
Suspended------------------- Q = O.I25 Qi•3s
s
Bedload--------------------- Qs = 0.702 Qo.so
Sand and gravel-------------
Silt and clay---------------
0.062-0.25 mm---------------
0.25-1.0 mm-----------------
Q =
s 0.0160 Qi.4s
Q =
s 0.486 Qi.i2
Q =
s 0.004545 Qi.77
Q =
s 0.0904 Qi.is
0.79 67 31
0.76 $8 33
0.54 79 31
0.82 73 31
0.56 116 31
0.88 65 31
0.55 130 31
Coarser than 1.0------------ Qs = 0.147 Q°•76 0.24 201 31
Juan River near Bluff, Utah (Leopold and others, 1964, p. 230}, exhibit con-
spicuous differences in the relation of sediment discharge to water discharge
during rising spring flows and recessional summer flows. As a result of
obser"vations during the 1982 field season, in which suspended sediment concen-
trations during rising streamflows appeared to be generally higher than
concentrations during recessional streamflows, it was suspected that seasonal
differences in sediment discharge may be typical of the Yampa River at
Deerlodge Park.
Streamflow and sediment discharge data were reexamined to determine the
significance of seasonality on sediment transport through Deerlodge Park.
Sediment discharge and water discharge data from 1982 and 1983 were subdivided
into groups on the basis of occurrence during the rising hydrograph or the
recessional hydrograph. Measurements made from February through May were
categorized as rising-hydrograph measurements, and those made from June
through July were categorized as recessional-hydrograph measurements. ~east-
squares linear-regression equations describing measured sediment discharge as
a function of water discharge, similar to those in table 3, were recomputed
from data in the subgroups. The regression equation slope and intercept
values from both subgroups were analyzed with a Student t-test to determine
whether significant differences existed between sediment discharge relations
associated with rising and recessional hydrographs. At the 95-percent level
of significance, no differences between the sediment transport equations
representing rising and recessional hydrographs were confirmed for total
sediment discharge, suspended-sediment discharge, or the discharge of sediment
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