WSP07706

• File Number: 8200.765
• Description: White River General
• State: CO
• Basin: Yampa/White
• Water Division: 6
• Date: 1/1/1993
• Author: USGS
• Title: Sediment Transport and Water-Quality Characteristics and Loads - White River - Northwestern Colorado - Water Years 1975 through 1988
• Water Supply Pro - Doc Type: Report/Study

nrJ'7S5

Table 3. Regression Information used to determine suspended-sediment loads in the White River at sites 1-4,
water years 1975-88, sites 5 and 6, water years 1983-88, and station 09306300, water years 1975-81

[Lsd. daily suspended~sediment load in tons per day; ~. daily discharge in cubic feet per second. Hydrologic events are: (l) Rising and peak Sb'eamOows
during spring and summer from snowmelt or storm runoff; (2) receding streamftows during spring and summer that follow peak runoff conditions; (3) base or near
constant streamRows during fall and winter]

Logarithm form (base 10)
log Lsd = a + b log Qd

Site

Hydro-
logic
event

Coefficients
(a) (b)

Standard
error
(SE)

Number
of
samples

Antlloga~thmdorm
lsd=10 Qd Cb

Variance
(S2)

Bias
correction
factor
(Cb)

I 1 14 -2.67 1.62 0.192
I 2,3 47 -3.04 1.65 0.267
2 1 12 -1.96 1.40 0.199
2 2,3 45 -3.17 1.68 0.378
3 1,2,3 59 -4.67 2.24 0.345
4 1 37 -1.11 1.27 0.313
4 2,3 103 -2.75 1.67 0.294
5 1 11 0.81 0.89 0.305
5 2,3 21 -3.26 1.93 0.349
6 I 60 -0.98 1.47 0.352
6 2 97 -2.66 1.87 0.407
6 3 121 -4.55 2.44 0.393
09306300 1 52 om 1.13 0.445
09306300 2 45 -1.36 1.45 0.349
09306300 3 130 -1.28 1.29 0.342
horizontal width of the sampler intake (Sw)' in feet;
number of verticals (N); and the time of sampling per
vertical (T), in seconds. Instantaneous bedload is cal-
culated as:
Lb = WbDwO.0952
SwNT (6)
Instantaneous bedload was compared with
instantaneous suspended-sediment load (table 4) to
determine if bedload was a substantial component of
sediment transport in the White River. For a stream-
discharge range of371 to 1,580 ft'!s, bedload in six
of the seven measurements at sites 1-4 was 3.3 percent
or less of the total sediment load. The bedload of
13.1 tons!d measured at site 3 on June 3, 1988, was
8.3 percent of the total sediment load. Although the

0.037 1.103 Lsd = 10-2.67 Q/621.1 03
0.071 1.207 Lsd = 1O-3.04Qdl.651.207
0.040 1.112 Lsd = 10- l.96Q/401.112
0.143 1.461 Lsd = 10-3.17 Q/681.461
0.119 1.371 Lsd = 1O-4.67Ql241.371
0.098 1.297 Lsd = 1O-t.1tQdl.271.297
0.086 1.256 Lsd = 1O-2.75Q/671.256
0.093 1.279 Lsd = 100.81QdO.891.279
0.122 1.382 Lsd = 1O-3.26Q/931.382
0.124 1.389 Lsd = 10-ll.98Q/471.389
0.166 1.553 Lsd = 1O-2.66Q/871.553
0.154 1.504 Lsd = 1O-4.55Ql441.504
0.198 1.690 Lsd = 100.01Q/131.690
0.122 1.381 Lsd = 10- l.36Q/45 1.381
0.117 1.363 Lsd = 1O-l.28Q/291.363

quantity of bedload measured at site 3 was not large
compared with the downstream bedload at site 6, the
percentage bedload of the total sediment load at site 3
seems unusually large; the measurement may represent
conditions of local, short-term, bedload movement.
Stream discharge in the data set for site 6 (table 4)
ranged from 599 to 6,090 ft'!s. Bedload at site 6 was
1.3 percent or less of the total sediment load for all
18 measurements. Because the measured bedload in
the White River generally was a small component of
the total sediment load in comparison with the
suspended-sediment load, it was not included in the
estimates of annual sediment loads or annual capacity
losses in reservoirs at sites 1-6.

Because values of daily stream discharge were
unavailable at sites 5 and 6 for water years 1975-82,
regressions and data comparisons were used to develop

SEDIMENT TRANSPORT 17