Flaming Gorge Unit

On May 24, 1869, Major John Wesley Powell and his crew of nine men began a daring three-month expedition down the Green and Colorado rivers. On May 27, three days after they set out from Green River, Wyoming, they reached the Uinta Mountains in their small wooden boats and were impressed by the beauty of the sun’s reflection off the brilliant red gorge that looked from a distance as if it were on fire. Powell and his men named the canyon ‘Flaming Gorge’ then continued their successful trip downstream completing their journey in the late summer.

Construction of Flaming Gorge Dam, as part of the Colorado River Storage Project, began in June 1958 with the last bucket of concrete placed on November 15, 1962. The 502 foot-high thin-arch concrete dam is located on the Green River in northeastern Utah about 32 miles downstream from the Utah-Wyoming border. Flaming Gorge Dam is one of the four units of the CRSP, which provides vital water storage and hydropower generation as well as many recreation benefits.

On December 10, 1962, the waters of the Green River began filling the reservoir behind Flaming Gorge Dam and nearly a year later on September 27, 1963, President John F. Kennedy initiated the first power generation at Flaming Gorge Powerplant. The dam was dedicated on August 17, 1964, by former First Lady, Claudia “Lady Bird” Johnson.

There are three generating units in the Flaming Gorge Powerplant, with a total installed capacity of about 150 megawatts. The powerplant produces approximately 500,000,000 kilowatt hours of energy annually which is enough to serve about 50,000 households. The power produced by Flaming Gorge Powerplant is distributed by the Western Area Power Administration to Wyoming, Utah, Colorado, New Mexico, Arizona, Nebraska, and Nevada.

Flaming Gorge Reservoir extends as far as 91 mi upstream and is part of Flaming Gorge National Recreation Area, administered by the U.S. Forest Service. When the reservoir is full at elevation 6,040 feet above sea level, it has a capacity of 3,788,900 acre-feet and a surface area of 42,020 acres.Within the reservoir area, there are two distinct types of land: a mountainous area in Utah composed of benches, canyons, and forest; and a desert area in Wyoming composed of low hills, shale badlands, and desert shrubs. These diverse areas provide habitat for a variety of birds and animals such as deer, elk, bighorn sheep, pronghorn antelope, prairie dogs, Steller’s jays, Clark’s nutcrackers, and eagles.

The community of Dutch John, Utah, located about two miles northeast of the dam, was founded by the Secretary of the Interior in 1958 as a community to house personnel, administrative offices, and equipment for construction and operation of Flaming Gorge Dam and Powerplant. The community was named for a pioneer settler of the area. Dutch John was managed by Reclamation as a residential area to house staff involved in the operation, maintenance, and administration of the dam, until 1998 when it was transferred to the local government.

Related Resources
Colorado River Storage Project

Looking for water data? WATER OPERATIONS

Flaming Gorge Dam is a water storage unit of the Colorado River Storage Project (CRSP). The CRSP was authorized on April 11, 1956 to regulate the flow of the Colorado River; provide for flood control; provide for storage and delivery of water for irrigation, municipal, industrial, and other beneficial purposes; and generate electrical power. The CRSP also provides for recreation and improves conditions for fish and wildlife. Construction of the CRSP ater storage facilities, including Flaming Gorge Dam, was critical to the development of the Upper Colorado River Basin’s water and power resources.

Flaming Gorge Dam and Powerplant were constructed by the Bureau of Reclamation and were dedicated in 1964. The powerplant consists of three hydroelectric generating units with a combined capacity of about 151 megawatts and is part of the CRSP power resources. The capacity of the generating units has been increased from the original capacity through the application of new technology and other worked performed in the powerplant as repair or replacement of equipment occurred due to normal “wear and tear” and aging. For the period between 1964 and 2006 the average annual generation from the powerplant was 497,129,000 kilowatt-hours which is enough electricity to supply the annual needs of about 50,000 households. Operation and maintenance of the dam and powerplant are performed by employees of the Flaming Gorge Field Division of the Power Office and are funded from revenues received from the sale of CRSP power.

The initial operation of Flaming Gorge Dam focused primarily on regulating the flow of the Green River and generating hydroelectric power. However, the storage and use of water altered natural flow patterns, water temperatures, and water quality of the Green River. While non-native fish (trout) populations downstream of the dam flourished, native fish populations and their habitat were modified or adversely affected in part by construction and subsequent operation of the dam. Except for high flows in the springtime to encourage geese to nest at high ground, there were no environmental constraints on water storage and power generation. Generally, downstream releases fluctuated to meet power demands. In 1974, a 400 cubic-feet per second minimum release was established; but under normal conditions a minimum release of 800 cubic-feet per second was implemented to improve the tailwater trout fishery and boating. In 1977 and 1978, the dam was retrofitted with a selective withdrawal structure to increase water temperatures for the tailwater trout fishery.

Under the Endangered Species Act of 1973, operations began to change to accommodate endangered fish research and recovery efforts. In 1985, an interim flow agreement was established between Reclamation and the U.S. Fish and Wildlife Service to change releases from the dam to protect critical nursery habitats for endangered fishes in the Green River downstream from Jensen, Utah. In general, flows became more stable with less fluctuation to meet power demands. Along with these changes, numerous research releases took place to support preparation of the Final Biological Opinion on the Operation of Flaming Gorge Dam which was issued by the Service on November 25, 1992. The opinion stated that the operation of Flaming Gorge Dam at that time was likely to jeopardize the continued existence of the endangered fish in the Green River and outlined elements of a Reasonable and Prudent Alternative that would offset jeopardy to the endangered fishes.

In 1993, Reclamation began making releases from the dam in an attempt to meet the flow and temperature recommendations outlined in the 1992 Biological Opinion issued by the Service. These recommendations were based on the most current scientific data available at that time. One of the actions identified in the opinion was to collect more information about the flow and temperature needs of the endangered fishes to refine or modify the recommendations in the 1992 opinion. A five-year research study began in 1992 resulting in additional data and flow and temperature refinements that were included in the 2000 Flow and Temperature Recommendations published by the Upper Colorado River Endangered Fish Recovery Program (Recovery Program). Established in 1987, the Recovery Program is a cooperative effort among the states of Utah, Colorado, and Wyoming, environmental and water user organizations, federal agencies including the National Park Service, Reclamation, Service, and Western Area Power Administration (Western), and the Colorado River Energy Distributors Association.

Under the National Environmental Policy Act, Reclamation undertook preparation of an environmental impact statement (EIS) on the operation of Flaming Gorge Dam in 2000 to describe the effects of operating the dam to achieve the temperature and flows specified in the Recovery Program’s September 2000 Flow and Temperature Recommendations, and to comply with Section 7 of the Endangered Species Act. The EIS was completed in November 2005 and the Record of Decision (ROD) was signed February 16, 2006. Implementation of the ROD began with the spring 2006 runoff season.

The operational changes made to accommodate the flow recommendations, beginning with the 1992 Biological Opinion and followed by the ROD in 2006, have impacted power generation at Flaming Gorge Dam by reducing flexibility and changing generation patterns. Water that bypasses the powerplant cannot generate power resulting in a loss in revenues. Water moved from the summer and winter peak power demand seasons to provide high spring flows for the endangered fishes may necessitate increased generation from coal or other non-hydro generation resources and could have other cost and environmental impacts. The capacity of the powerplant and load following is restricted except for response to power system emergencies.

A Flaming Gorge Technical Work Group was established by the ROD in 2006 consisting of biologists and hydrologists from the Service, Western, and Reclamation. Its objective is to consider flow requests from the Recovery Program and provide proposals to Reclamation for flow and temperature regimes to best achieve ROD objectives for the endangered fish based on current year hydrologic conditions.

The Flaming Gorge Working Group, formed in 1993, meets three times a year to provide a forum for information exchange and for public or special interest groups to express their views on the operation of Flaming Gorge Dam. Information from the Flaming Gorge Technical Work Group and Recovery Program is also available to the Flaming Gorge Working Group. Reclamation considers input from the Flaming Gorge Working Group in its decision to operate Flaming Gorge to best achieve ROD objectives for the endangered fish consistent with CRSP purposes.

Related Resources
Colorado River Storage Project
Flaming Gorge Operational Data

The Green River's headwaters are in the Wind River Mountains in Wyoming. Sixty miles below Green River, Wyoming, the river enters the first of many deep canyons, including Flaming Gorge. The name Flaming Gorge was given when Major John Wesley Powell and his company saw the sun reflecting off the brilliant, flaming red rocks as they explored the Green and Colorado Rivers. The waters of the Green River are stored behind Flaming Gorge Dam as part of the Colorado River Storage Project. Flaming Gorge Reservoir extends as far as 91 miles to the north and provides many recreational opportunities as part of the Flaming Gorge National Recreation Area.

Flaming Gorge Dam History
Construction authorized April 11, 1956
First construction contract award (temporary access road) January 4, 1957
Prime contract award June 18, 1958
Diversion of Green River around damsite August 17, 1959
First bucket of concrete September 18, 1960
Last bucket of concrete November 15, 1962
Start of storage in reservoir December 10, 1962
First power generated September 27, 1963
Last generator completed February 12, 1964
Dedicated by Claudia “Lady Bird” Johnson August 17, 1964
Flaming Gorge Dam
Height above bedrock 502 feet (153 meters)
Height above original river channel 455 feet (139 meters)
Crest length ( arch length at axis of dam) 1,285 feet (392 meters)
Volume of concrete:
Dam only
Powerplant & misc.
Total concrete

Dam only
54,843 cubic yards (41,930 cubic meters)
1,041,487 cubic yards (796,274 cubic meters)
Cost of dam $49,600,000
Flaming Gorge Powerplant
Number of generating units 3
Installed capacity 150 megawatts
Average annual power generation 500,000 megawatt hours
Cost of powerplant & switchyard $65,300,000
Flaming Gorge Reservoir
Capacity, full (6,040 feet total) 3,788,799 acre-feet (4,674 million cubic meters)
Active capacity J3,749,000 acre-feet (4,624 million cubic meters)
Depth of water at dam (when full) 436 feet (133 meters)
Miles of shoreline (when full) 375 miles (604 kilometers)

From 1979 to 1984, Flaming Gorge Dam operations were evaluated for potential effects on four endangered fish species found in the Green and Colorado River basins: Colorado pikeminnow, humpback chub, razorback sucker, and bonytail. Releases from the dam were modified from 1985 to 1991 in an effort to benefit the endangered fish and allow summer flow regimes in the Green River that could be tested and evaluated. In 1987, the Upper Colorado River Endangered Fish Recovery Program (Recovery Program) was initiated to protect and recover the endangered fish species of the Upper Colorado River Basin so they no longer require protection under the Endangered Species Act (ESA). The states of Colorado, Wyoming and Utah; Reclamation, Western Area Power Administration, U.S. Fish and Wildlife Service; and environmental, water and power user organizations, are all participants in the Recovery Program.

Flaming Gorge Dam

In 1992, the U.S. Fish and Wildlife Service issued a Biological Opinion on the operation of Flaming Gorge Dam which contained a reasonable and prudent alternative (RPA) to current operations of the dam which would not jeopardize the endangered fish. Reclamation operated Flaming Gorge Dam to achieve the objectives described in the RPA from 1992 until February of 2006. Part of this RPA was to conduct additional research to determine what flow and temperature conditions were necessary for the recovery of the endangered fish. In September of 2000, the recovery program issued the Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Gorge Dam (2000, Muth et. al.)

A Final Environmental Impact Statement (EIS) on the Operation of Flaming Gorge Dam was finalized in November 2005 with a Record of Decision (ROD) following in February 2006. The EIS describes the effects of operating Flaming Gorge Dam to achieve the temperature and flows recommended in the September 2000 Flow and Temperature Recommendations (2000, Muth et. al.) and to comply with Section 7 of the ESA. Part of the commitments outlined in the ROD include implementation of an adaptive management approach for the long-term management of the dam to allow for future operational modifications based on continued research and new scientific information.

Implementation of an adaptive management process provides a framework for a collaborative, iterative process of experimentation, evaluation, and modification necessary to achieve improved results over time. As new knowledge is gained through the adaptive management process, operations can be refined to improve conditions for the four endangered fish while maintaining the authorized purposes of the dam.

The adaptive management process for Flaming Gorge Dam will rely on on-going or additional Recovery Program activities to monitor, study, and test the outcomes of flow modifications and release temperatures from Flaming Gorge Dam. The Flaming Gorge Working Group, which meets twice a year, will continue to function as the primary means of information gathering and dissemination with stakeholders, interested parties and the public. The Flaming Gorge Working Group is a forum where stakeholders and the public can share concerns and comments with Reclamation regarding the operation of Flaming Gorge Dam.

Reclamation follows four planning steps when developing an operational plan for Flaming Gorge Dam. These steps are intended to integrate the concept of adaptive management into the planning process:

  • Request for research flows from the Recovery Program
  • Development of spring proposal from the FGTWG which incorporates the request with ROD objectives
  • Solicitation of comments from the Flaming Gorge Working Group regarding the spring proposal
  • Final decision from Reclamation on how best to achieve the objectives of the proposal

Related Resources
Colorado River Storage Project

Flaming Gorge Dam Environmental Impact Statement

The Bureau of Reclamation prepared an environmental impact statement (EIS) on the operation of Flaming Gorge Dam. The EIS describes the effects of operating Flaming Gorge Dam to achieve the flows recommended by the Recovery Implementation Program for Endangered Fish Species in the Upper Colorado River Basin (Recovery Program) and comply with Section 7 of the Endangered Species Act.

The purpose of the proposed action is to protect and assist in the recovery of the populations and designated critical habitat of the four endangered fishes found in the Green and Colorado River Basins:

  • razorback sucker (Xyrauchen texanus)
  • Colorado pikeminnow (Ptychocheilus lucius)
  • humpback chub (Gila cypha)
  • bonytail (Gila elegans)

This action is necessary so that, along with other activities of the Recovery Implementation Program Action Plan (Recovery Action Plan), the fish no longer require protection under the Endangered Species Act, while continuing the other authorized purposes of the Flaming Gorge Unit of the Colorado River Storage Project.

The Flaming Gorge National Recreation Area was established by Congress in October 1968. The NRA encompasses approximately 201,000 acres of scenic land surrounding Flaming Gorge Reservoir’s 375 miles of shoreline which extends as far as 91 miles to the north.

Flaming Gorge Recreation Area

The recreation facilities at Flaming Gorge Reservoir are managed by the U.S.Forest Service as part of the Ashley National Forest, and include boat ramps, marinas, and campgrounds. The NRA offers numerous and varied recreation activities such as fishing, boating, swimming, camping, rock climbing, windsurfing, water skiing, scuba diving. Fishing, however, is by far the most popular activity. Flaming Gorge Reservoir has become nationally known for the spectacular fishing available in the reservoir’s cool clear water which is ideal for growing large trout. The famous angling waters of the reservoir have produced state and world record size lake trout, German brown trout, and rainbow trout. The reservoir also supports cutthroat trout, kokanee salmon, smallmouth bass, and channel catfish.

Below the dam, the Green River is famous for its blue-ribbon trout fishing and white water rafting opportunities. The scenic beauty of the canyon setting enhances the experience of rafting the white water rapids, fishing, or hiking the Little Hole National Trail. One of the most breath-taking scenes in the area is Firehole Canyon, south of Rock Springs off US Highway 191, which features beautiful formations reflecting in the blue water of the reservoir.

Flaming Gorge Visitor Center/Guided Tour Schedule

Flaming Gorge Dam Visitor Center will be closed for the season beginning October 16 and will reopen April 15.

When the visitor center is open, the public will be able to access exhibits inside the visitor center and use facilities during normal hours. Guided tours of the dam will not be offered, but a portion of the walkway will allow visitors to view the riverside of the dam.

April 15 to Memorial Day Weekend:
Visitor center open daily from 9 a.m. - 4 p.m.

Memorial Day Weekend Through Labor Day Weekend:
Visitor center open daily from 9 a.m. - 5 p.m.

Labor Day Weekend to October 15:
Visitor center open daily from 9 a.m. - 4 p.m.


For more information, contact the Flaming Gorge Field Division at (435) 885-3106 or the Flaming Gorge Visitor Center at (435) 885-3135.

Related Resources
Colorado River Storage Project
Ashley National Forest

Last Updated: 11/2/23