Flaming Gorge Dam
Encyclopedia
The Flaming Gorge Dam is a concrete thin-arch dam in the Flaming Gorge of the Green River
, a major tributary of the Colorado River
, in the U.S. state
of Utah
. One of the largest dams in the American West, Flaming Gorge Dam forms the Flaming Gorge Reservoir
, which extends 91 miles (146.4 km) into southern Wyoming
, submerging four distinct gorges of the Green River. The dam stores water for the Colorado River Storage Project
, which stores and distributes upper Colorado River Basin water. The dam's hydroelectric power plant generates 151.5 MW.
Situated in Flaming Gorge, a canyon of the Green River named by John Wesley Powell
, the dam was built and is operated by the U.S. Bureau of Reclamation. Groundbreaking for the structure began in 1958 and was completed in 1964. The completed structure is 502 feet (153 m) high and 1180 feet (359.7 m) long, with three hydroelectric generators. With no fish ladder
s, elevators or any means of passage for aquatic species, the dam has severely hurt native species. By creating a standing-water pool on a sediment-laden river, the dam has caused the lower Green to lose its sediment load and decrease in temperature, further hurting the native ecosystem.
The Flaming Gorge Reservoir is a popular recreation spot, although it is nowhere as well known as Lake Powell
around 400 miles (643.7 km) to the south. Below the dam, although the morphology and flows of the river now depend on peaking power releases, the Green River is still an excellent stream for whitewater rafting and is a "Blue Ribbon Trout Fishery".
, primarily south to its confluence with the Colorado River in Canyonlands National Park
. Near the town of Green River, Wyoming
, the river continues south through four major canyons - including Red Canyon and Flaming Gorge - then makes a great bend to the east, and then west and south past the Uinta Mountains
. The largest and most important tributary of the Colorado River, the Green's watershed is actually larger than that of the Colorado upstream of their confluence.
Specifically about 10 miles (16.1 km) west of the present-day town of Dutch John, the Green River enters a steep and narrow gorge that winds eastward in several trapped meander
s. Just downstream of the confluence with Cart Creek, where Cart Creek Bridge now stands, the Green turns south and enters a section where the canyons become extremely narrow, only 1000 to 1500 ft (304.8 to 457.2 m) wide. The Flaming Gorge Dam was built in this canyon in 1964.
, which hunted game near Flaming Gorge, during prehistoric periods. The Ute
tribes came later and spread throughout mountainous regions in what are now the present-day states of Colorado
and Utah
. In the early 19th century, fur trappers began searching the area for beaver
. This led to the first exploration of the Green River, by William H. Ashley
, one of the organizers of the Rocky Mountain Fur Company
. Far later, in 1869, famed explorer John Wesley Powell
and nine men started an expedition of the Green River and the Colorado River
. Powell gave Flaming Gorge its present name after seeing the "sun reflecting off the red rocks", although Red Canyon, was to them, more impressive than Flaming Gorge, with its far more dangerous rapids. With new knowledge of the area, ranchers and pioneers moved to the area beginning in the 1870s. Many outlaws and fugitives, including Butch Cassidy
and the Wild Bunch
, would hide in isolated canyons along the Green River.
The cancellation of Echo Park Dam, a proposal in the scenic downstream Green River canyon of Echo Park
, was won by environmentalists primarily from the Sierra Club
, at that time led by David Brower. Having never seen Flaming Gorge and Glen Canyon
until construction had begun on both dams, Brower had suggested that a "sacrifice" should be made in order to preserve Echo Park. The famous quote:
prompted Congress to reject this proposal. However, when both dams had already begun construction, it was said that Brower vowed to
Although Flaming Gorge is nowhere as well known as Glen Canyon, he had still quoted it as "part" of the sacrifice. While Glen Canyon was the primary "replacement", Flaming Gorge provided additional storage.
Construction of the Flaming Gorge Dam began in 1958 under the direction of the Bureau of Reclamation, and ended in 1964 with the completion of its three generators, each rated at 36,000 kilowatts. The town of Dutch John, with a population of three thousand at the peak of construction, was a company town
built to house construction workers. The reservoir first filled to its highest capacity in August 1974. The construction of the dam resulted in permanent changes to the ecosystem of the Green River. 91 miles (146.4 km) of the river was flooded to become Flaming Gorge Reservoir
. Prior to the construction of the dam, the Green was a highly seasonal, silty and warm river, with greatly fluctuating flows throughout the year. After the dam was built, the river temperature dropped and silt was trapped in the reservoir. Sandbars downstream of the dam ceased to replenish and the habitat of native fish disappeared, in similar fashion to the Grand Canyon when Glen Canyon Dam
was built. Despite the lower Green being a "Blue Ribbon Trout Fishery", many native fish have been lost.
On August 11, 1977, one of the turbines, Unit 2, jammed after one of the sealing rings on the penstock failed. This event led to the seal rings on all three penstocks being replaced. These seal rings also failed, and were replaced again. However, no major structural damage to the dam occurred. The generators were each uprated to 50,650 kilowatts each from August 1990 to April 1992.
The Flaming Gorge Dam is 502 feet (153 m) high above the Green River. It measures 1180 feet (359.7 m) long along its crest and its maximum base thickness is 131 feet (39.9 m), while its crest thickness is 27 feet (8.2 m). The dam contains about 987000 cubic yards (754,615.6 m³) of concrete. The reservoir of the dam is approximately 6040 feet (1,841 m) in elevation at full pool.
The dam's hydroelectric power plant is located at its base. It consists of three 50,650 kilowatt generators, powered by three Francis
design turbines of 50000 hp. The total nameplate generating capacity of the Flaming Gorge Dam is 151,950 kilowatts. Three 10 feet (3 m) diameter penstock
s feed water to the power plant. The Bureau of Reclamation operates the power plant, and the Western Area Power Administration
markets the power generated by the dam.
Excess water is spilled through a 675 feet (205.7 m) long tunnel spillway that runs through the left abutment of the dam. Controlled by two 16.75 feet (5.1 m) by 34 feet (10.4 m) gates, the tunnel has a capacity of 28800 ft3 per second. At its upstream end it is 26.5 feet (8.1 m) in diameter, and at the discharge point is 18 feet (5.5 m) in diameter. The dam also has an outlet works, which consists of two 72 inches (1.8 m) diameter steel pipes through the dam. The discharge capacity of the outlet works is 4000 ft3 per second.
, and as a result crucial habitat of four species of native fish, in the lower Green River. Introduced brown trout
, rainbow trout
, and lake trout
have caused increased damage to these habitats. On August 28, 2008, the Bureau of Reclamation prepared an EIS (Environmental Impact Statement) on the operation of the dam to meet the river flow required by the Recovery Implementation Program for Endangered Fish Species and Section 7 of the Endangered Species Act
. The four native fishes affected by Flaming Gorge and Glen Canyon dams are: the razorback sucker
, Colorado pikeminnow
, humpback chub
, and bonytail chub
.
In 2006, the dam began a release pattern more similar to historical discharges along the Green River, intended to assist the dropping native fish populations.
Green River (Utah)
The Green River, located in the western United States, is the chief tributary of the Colorado River. The watershed of the river, known as the Green River Basin, covers parts of Wyoming, Utah, and Colorado. The Green River is long, beginning in the Wind River Mountains of Wyoming and flowing...
, a major tributary of the Colorado River
Colorado River
The Colorado River , is a river in the Southwestern United States and northwestern Mexico, approximately long, draining a part of the arid regions on the western slope of the Rocky Mountains. The watershed of the Colorado River covers in parts of seven U.S. states and two Mexican states...
, in the U.S. state
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...
of Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
. One of the largest dams in the American West, Flaming Gorge Dam forms the Flaming Gorge Reservoir
Flaming Gorge Reservoir
Flaming Gorge Reservoir is a reservoir in Wyoming and Utah, on the Green River, created by Flaming Gorge Dam. Construction on the dam began in 1958 and was completed in 1964...
, which extends 91 miles (146.4 km) into southern Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
, submerging four distinct gorges of the Green River. The dam stores water for the Colorado River Storage Project
Colorado River Storage Project
The Colorado River Storage Project is a United States Bureau of Reclamation project designed to oversee the development of the upper Colorado River basin...
, which stores and distributes upper Colorado River Basin water. The dam's hydroelectric power plant generates 151.5 MW.
Situated in Flaming Gorge, a canyon of the Green River named by John Wesley Powell
John Wesley Powell
John Wesley Powell was a U.S. soldier, geologist, explorer of the American West, and director of major scientific and cultural institutions...
, the dam was built and is operated by the U.S. Bureau of Reclamation. Groundbreaking for the structure began in 1958 and was completed in 1964. The completed structure is 502 feet (153 m) high and 1180 feet (359.7 m) long, with three hydroelectric generators. With no fish ladder
Fish ladder
A fish ladder, also known as a fishway, fish pass or fish steps, is a structure on or around artificial barriers to facilitate diadromous fishes' natural migration. Most fishways enable fish to pass around the barriers by swimming and leaping up a series of relatively low steps into the waters on...
s, elevators or any means of passage for aquatic species, the dam has severely hurt native species. By creating a standing-water pool on a sediment-laden river, the dam has caused the lower Green to lose its sediment load and decrease in temperature, further hurting the native ecosystem.
The Flaming Gorge Reservoir is a popular recreation spot, although it is nowhere as well known as Lake Powell
Lake Powell
Lake Powell is a huge reservoir on the Colorado River, straddling the border between Utah and Arizona . It is the second largest man-made reservoir in the United States behind Lake Mead, storing of water when full...
around 400 miles (643.7 km) to the south. Below the dam, although the morphology and flows of the river now depend on peaking power releases, the Green River is still an excellent stream for whitewater rafting and is a "Blue Ribbon Trout Fishery".
Site
The Green River flows 730 miles (1,174.8 km) from its headwaters in the Wind River Mountains of WyomingWyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...
, primarily south to its confluence with the Colorado River in Canyonlands National Park
Canyonlands National Park
Canyonlands National Park is a U.S. National Park located in southeastern Utah near the town of Moab and preserves a colorful landscape eroded into countless canyons, mesas and buttes by the Colorado River, the Green River, and their respective tributaries. The park is divided into four districts:...
. Near the town of Green River, Wyoming
Green River, Wyoming
Green River is a city in and the county seat of Sweetwater County, Wyoming, United States, in the southwestern part of the state. The population was 11,808 at the 2000 census....
, the river continues south through four major canyons - including Red Canyon and Flaming Gorge - then makes a great bend to the east, and then west and south past the Uinta Mountains
Uinta Mountains
The Uinta Mountains are a high chain of mountains in northeastern Utah and extreme northwestern Colorado in the United States. A subrange of the Rocky Mountains, they are unusual for being the highest range in the contiguous United States running east to west, and lie approximately east of Salt...
. The largest and most important tributary of the Colorado River, the Green's watershed is actually larger than that of the Colorado upstream of their confluence.
Specifically about 10 miles (16.1 km) west of the present-day town of Dutch John, the Green River enters a steep and narrow gorge that winds eastward in several trapped meander
Meander
A meander in general is a bend in a sinuous watercourse. A meander is formed when the moving water in a stream erodes the outer banks and widens its valley. A stream of any volume may assume a meandering course, alternately eroding sediments from the outside of a bend and depositing them on the...
s. Just downstream of the confluence with Cart Creek, where Cart Creek Bridge now stands, the Green turns south and enters a section where the canyons become extremely narrow, only 1000 to 1500 ft (304.8 to 457.2 m) wide. The Flaming Gorge Dam was built in this canyon in 1964.
History
The Flaming Gorge area was prehistorically inhabited by people of the Fremont cultureFremont culture
The Fremont culture or Fremont people is a pre-Columbian archaeological culture which received its name from the Fremont River in the U.S. state of Utah where the first Fremont sites were discovered. The Fremont River itself is named for John Charles Frémont, an American explorer. It inhabited...
, which hunted game near Flaming Gorge, during prehistoric periods. The Ute
Ute Tribe
The Ute are an American Indian people now living primarily in Utah and Colorado. There are three Ute tribal reservations: Uintah-Ouray in northeastern Utah ; Southern Ute in Colorado ; and Ute Mountain which primarily lies in Colorado, but extends to Utah and New Mexico . The name of the state of...
tribes came later and spread throughout mountainous regions in what are now the present-day states of Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
and Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
. In the early 19th century, fur trappers began searching the area for beaver
Beaver
The beaver is a primarily nocturnal, large, semi-aquatic rodent. Castor includes two extant species, North American Beaver and Eurasian Beaver . Beavers are known for building dams, canals, and lodges . They are the second-largest rodent in the world...
. This led to the first exploration of the Green River, by William H. Ashley
William Henry Ashley
William Henry Ashley was a pioneering fur trader, entrepreneur, and politician. Though a native of Virginia, Ashley had already moved to St. Genevieve in what was then called Louisiana, when it was purchased by the United States from France in 1803...
, one of the organizers of the Rocky Mountain Fur Company
Rocky Mountain Fur Company
The Rocky Mountain Fur Company, sometimes called Ashley's Hundred, was organized in St. Louis, Missouri in 1823 by General William H. Ashley and Major Andrew Henry . They posted advertisements in St. Louis newspapers seeking "One Hundred enterprising young men . ....
. Far later, in 1869, famed explorer John Wesley Powell
John Wesley Powell
John Wesley Powell was a U.S. soldier, geologist, explorer of the American West, and director of major scientific and cultural institutions...
and nine men started an expedition of the Green River and the Colorado River
Colorado River
The Colorado River , is a river in the Southwestern United States and northwestern Mexico, approximately long, draining a part of the arid regions on the western slope of the Rocky Mountains. The watershed of the Colorado River covers in parts of seven U.S. states and two Mexican states...
. Powell gave Flaming Gorge its present name after seeing the "sun reflecting off the red rocks", although Red Canyon, was to them, more impressive than Flaming Gorge, with its far more dangerous rapids. With new knowledge of the area, ranchers and pioneers moved to the area beginning in the 1870s. Many outlaws and fugitives, including Butch Cassidy
Butch Cassidy
Robert LeRoy Parker , better known as Butch Cassidy, was a notorious American train robber, bank robber, and leader of the Wild Bunch Gang in the American Old West...
and the Wild Bunch
Wild Bunch
The Wild Bunch, also known as the Doolin–Dalton Gang or the Oklahombres, was a gang of outlaws based in the Indian Territory that terrorized Kansas, Missouri, Arkansas, and Oklahoma Territory during the 1890s—robbing banks and stores, holding up trains, and killing lawmen. They were...
, would hide in isolated canyons along the Green River.
The cancellation of Echo Park Dam, a proposal in the scenic downstream Green River canyon of Echo Park
Echo Park (Colorado)
Echo Park is a remote river bottom surrounded by canyon walls on the Green River in Dinosaur National Monument. It was first mapped and given its name by the Powell Geographic Expedition in 1869. A proposed dam at Echo Park turned into a nationwide environmental controversy in the early 1950s...
, was won by environmentalists primarily from the Sierra Club
Sierra Club
The Sierra Club is the oldest, largest, and most influential grassroots environmental organization in the United States. It was founded on May 28, 1892, in San Francisco, California, by the conservationist and preservationist John Muir, who became its first president...
, at that time led by David Brower. Having never seen Flaming Gorge and Glen Canyon
Glen Canyon
Glen Canyon is a canyon that is located in southeastern and south central Utah and northwestern Arizona within the Vermilion Cliffs area. It was carved by the Colorado River....
until construction had begun on both dams, Brower had suggested that a "sacrifice" should be made in order to preserve Echo Park. The famous quote:
prompted Congress to reject this proposal. However, when both dams had already begun construction, it was said that Brower vowed to
Although Flaming Gorge is nowhere as well known as Glen Canyon, he had still quoted it as "part" of the sacrifice. While Glen Canyon was the primary "replacement", Flaming Gorge provided additional storage.
Construction of the Flaming Gorge Dam began in 1958 under the direction of the Bureau of Reclamation, and ended in 1964 with the completion of its three generators, each rated at 36,000 kilowatts. The town of Dutch John, with a population of three thousand at the peak of construction, was a company town
Company town
A company town is a town or city in which much or all real estate, buildings , utilities, hospitals, small businesses such as grocery stores and gas stations, and other necessities or luxuries of life within its borders are owned by a single company...
built to house construction workers. The reservoir first filled to its highest capacity in August 1974. The construction of the dam resulted in permanent changes to the ecosystem of the Green River. 91 miles (146.4 km) of the river was flooded to become Flaming Gorge Reservoir
Flaming Gorge Reservoir
Flaming Gorge Reservoir is a reservoir in Wyoming and Utah, on the Green River, created by Flaming Gorge Dam. Construction on the dam began in 1958 and was completed in 1964...
. Prior to the construction of the dam, the Green was a highly seasonal, silty and warm river, with greatly fluctuating flows throughout the year. After the dam was built, the river temperature dropped and silt was trapped in the reservoir. Sandbars downstream of the dam ceased to replenish and the habitat of native fish disappeared, in similar fashion to the Grand Canyon when Glen Canyon Dam
Glen Canyon Dam
Glen Canyon Dam is a concrete arch dam on the Colorado River in northern Arizona in the United States, just north of Page. The dam was built to provide hydroelectricity and flow regulation from the upper Colorado River Basin to the lower. Its reservoir is called Lake Powell, and is the second...
was built. Despite the lower Green being a "Blue Ribbon Trout Fishery", many native fish have been lost.
On August 11, 1977, one of the turbines, Unit 2, jammed after one of the sealing rings on the penstock failed. This event led to the seal rings on all three penstocks being replaced. These seal rings also failed, and were replaced again. However, no major structural damage to the dam occurred. The generators were each uprated to 50,650 kilowatts each from August 1990 to April 1992.
Dimensions and operations
The dam's hydroelectric power plant is located at its base. It consists of three 50,650 kilowatt generators, powered by three Francis
Francis turbine
The Francis turbine is a type of water turbine that was developed by James B. Francis in Lowell, Massachusetts. It is an inward-flow reaction turbine that combines radial and axial flow concepts....
design turbines of 50000 hp. The total nameplate generating capacity of the Flaming Gorge Dam is 151,950 kilowatts. Three 10 feet (3 m) diameter penstock
Penstock
A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydraulic turbines and sewerage systems. It is a term that has been inherited from the technology of wooden watermills....
s feed water to the power plant. The Bureau of Reclamation operates the power plant, and the Western Area Power Administration
Western Area Power Administration
The Western Area Power Administration markets and delivers hydroelectric power and related services within a 15-state region of the central and western U.S. It is one of four power marketing administrations within the U.S...
markets the power generated by the dam.
Excess water is spilled through a 675 feet (205.7 m) long tunnel spillway that runs through the left abutment of the dam. Controlled by two 16.75 feet (5.1 m) by 34 feet (10.4 m) gates, the tunnel has a capacity of 28800 ft3 per second. At its upstream end it is 26.5 feet (8.1 m) in diameter, and at the discharge point is 18 feet (5.5 m) in diameter. The dam also has an outlet works, which consists of two 72 inches (1.8 m) diameter steel pipes through the dam. The discharge capacity of the outlet works is 4000 ft3 per second.
Environmental impacts
The cold and sediment-lacking water released from the Flaming Gorge Dam, which averages from 800 ft3 to 4700 ft3 per second, has caused loss of sandbars, sedimentSediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
, and as a result crucial habitat of four species of native fish, in the lower Green River. Introduced brown trout
Brown trout
The brown trout and the sea trout are fish of the same species....
, rainbow trout
Rainbow trout
The rainbow trout is a species of salmonid native to tributaries of the Pacific Ocean in Asia and North America. The steelhead is a sea run rainbow trout usually returning to freshwater to spawn after 2 to 3 years at sea. In other words, rainbow trout and steelhead trout are the same species....
, and lake trout
Lake trout
Lake trout is a freshwater char living mainly in lakes in northern North America. Other names for it include mackinaw, lake char , touladi, togue, and grey trout. In Lake Superior, they can also be variously known as siscowet, paperbellies and leans...
have caused increased damage to these habitats. On August 28, 2008, the Bureau of Reclamation prepared an EIS (Environmental Impact Statement) on the operation of the dam to meet the river flow required by the Recovery Implementation Program for Endangered Fish Species and Section 7 of the Endangered Species Act
Endangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
. The four native fishes affected by Flaming Gorge and Glen Canyon dams are: the razorback sucker
Razorback sucker
The razorback sucker, Xyrauchen texanus, is an endangered fresh water sucker of rivers in the Colorado River drainage of western North America.-Description:...
, Colorado pikeminnow
Colorado pikeminnow
The Colorado pikeminnow Ptychocheilus lucius is the largest cyprinid fish of North America and one of the largest in the world, with reports of individuals up to 6 ft long and weighing over 100 pounds...
, humpback chub
Humpback chub
The humpback chub Gila cypha, is a federally protected fish that lived originally in fast waters of the Colorado River system in the United States. This species takes its name from the prominent hump between the head and dorsal fin, which is thought to direct the flow of water over the body and...
, and bonytail chub
Bonytail chub
The bonytail chub or bonytail, Gila elegans, is a cyprinid freshwater fish native to the Colorado River of Arizona, California, Colorado, Nevada and Utah in the southwestern United States...
.
In 2006, the dam began a release pattern more similar to historical discharges along the Green River, intended to assist the dropping native fish populations.