WSP10382

• File Number: 8200.760
• Description: Yampa River
• State: CO
• Basin: Yampa/White
• Water Division: 1
• Date: 6/27/1984
• Author: USGS
• Title: Sediment Transport in Lower Yampa River, Northwestern Colorado
• Water Supply Pro - Doc Type: Report/Study

Table 1.--Hgdraulic geometrg relations at station Q9260050 Yampa River
at Daerlodge Park

[W, channel width in feet; 5, mean depth in feet; a, mean velocity in feet
per second; Af' cross-sectional area in square feet; Q, instantaneous
discharge in cubic feet per second; R2, coefficient of determination;
SE, standard error of estimate in percent; n, sample size]

Regression equation R2 SE n
W = 178 QO.OS9____________~-------- 0.18 12 35
5 = 0.0227 QO.64___________________ .96 13 35
,
Q = 0.251 QO.30____________________ .91 9 35
Af = 4.04 QO.70_____________________ .98 10 35

Water surface slope varied about a mean of 0.00069, with standard deviation of
0.00014 and n of 12.

at the Maybell and Lily gages. Linear regression of log-transformed discharge
data resulted in the equation:

QO = 1.74 QrO.94, R2 = 0.98, SE = 18 ,

where:

Qo = daily mean discharge of Yampa River at Oeerlodge Park, in
ft3/s,
Qr = sum of daily mean discharges of Yampa River near Maybell
and Little Snake River near Lily, in ft3/s,
R2 = coefficient of determination, and
SE = standard error of estimate, in percent.

The regression equation gives about the same answer as simply summing the
upstream discharges when the discharge at Oeerlodge Park is about 10,000
ft3/s. However, when the discharge at Deerlodge Park is near 400 ft3/s, the
equation overestimates discharge by about 25 percent. Consequently, historic
discharges at the Deerlodge Park gage were estimated by summing historic
discharges of the' '{amp a River near ;"1aybel] gage and the Little Snake River
neat' Lily gage. The historic hydrograph of mean daily discharges for the
Yampa River at Deerlodge Park is presented in figure 5.

Water years 1982 and 1983 were characterized by high peak discharges, and
above-average annual streamfl ows. The 1982 instantaneous peak di scharge at

9