8188

• UCREFRP Catalog Number: 8188
• Author: Muth, R. T., et al.
• Title: Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Forge Dam.
• USFW Year: 2000.
• USFW - Doc Type: \
• Copyright Material: NO

Final Report

3-26

September 2000

Table 3.9.-Peak flow estimates (m3/s) for major tributaries of the Green River basin down-
stream of Flaming Gorge Dam. a

Yampa Little
Recurrence Interval River at Snake Duchesne White Price San Rafael
(Years) Maybell River Riverb River River River
2 286 138 108 110 116 45
5 368 207 187 153 195 68
10 419 252 232 181 246 85
25 479 314 286 215 306 105
50 521 360 320 238 345 119
100 564 411 348 261 382 140
200 603 462 374 283 416 150
a Periods of record for USGS stream gages are presented in Table 3.3.
b Peak flow estimates for the Duchesne River have not been adjusted to remove the effects of
regulation, although the ability to regulate the magnitude of peak flows through reservoir operations
is limited.

The Yampa River is essentially unregulated. Total reservoir-storage capacity in the Yampa
River basin is only 110 million m3, but in the Green River upstream of the Yampa River confluence,
there is approximately 5,200 million m3 of reservoir-storage capacity. Because there is limited
regulation in the Yampa River basin, the river maintains a natural seasonal pattern of flow. Peak
spring flows, which usually occur in late May, are high (Table 3.9), and base flows from August
through February are usually low. The large flow contribution from the Yampa River, with its natural
seasonal flow pattern, serves to ameliorate some of the effects of flow regulation in the Green River.

The Duchesne River basin is located entirely in Utah, and flow originates primarily from
the southern Uintah Mountains. A number of south-flowing tributaries combine to form the
Duchesne River, which then flows east and joins the Green River near Ouray, Utah. Unlike the
Yampa River, the Duchesne River is highly regulated and greatly depleted. Numerous water-
development projects alter the flow of the Duchesne River, including the Moon Lake Project,
Strawberry Valley Project, Provo River Project, Uintah Indian Irrigation Project, and Central Utah
Project. On the basis of estimates of irrigated acreage and consumptive-use calculations, the
Duchesne River historically produced about 947 million m3 of water annually. Federal projects and
private uses of Duchesne River basin water have resulted in an average annual depletion of 676
million m3 (USFWS 1998b).

The White River originates in the Flat Top Mountains in Colorado, flows in a westerly
direction, and joins the Green River near Ouray, Utah, just downstream of the confluence of the