Bridge Canyon Dam
Encyclopedia
Bridge Canyon Dam is a proposed dam in the lower Grand Canyon
of the Colorado River
, in northern Arizona
in the United States
. It would be located near Bridge Canyon Rapids in an extremely rugged and isolated portion of the canyon, roughly 235 miles (378.2 km) downstream of Lee's Ferry
and 30 miles (48.3 km) upstream of the current extent of Lake Mead
.
The project was considered seriously by the U.S. Bureau of Reclamation for a period of over twenty years from the early 1950s to 1968. If built, the dam would tower 740 feet (225.6 m) high, forming a reservoir stretching more than ninety miles (150 km) upstream, including thirteen miles (21 km) inside Grand Canyon National Park
. The dam would serve mainly for hydropower production and sediment retention in conjunction with several others further upstream including Marble Canyon Dam, on the Colorado, Green and other rivers.
Due to its enormous potential for environmental destruction and the dwindling flows of the Colorado River, the project stalled in 1968 after years of public opposition. However, the location is considered one of the best remaining sites for a large dam in the western United States.
Bridge Canyon Dam was first seriously considered in the 1940s as part of the Bureau of Reclamation's cascade of high power dams along the Colorado River system. Up to seven dams were proposed on the Colorado River alone, including Hoover
, Bridge Canyon, Marble Canyon (Redwall) and Glen Canyon
, and perhaps an additional one or two within Grand Canyon National Park. However, only Hoover and Glen Canyon were eventually built, as well as several others on tributaries.
In the 1940s, Reclamation began investigating potential sites for a dam in the lower Grand Canyon near the river's confluence with Diamond Creek, 25 to 40 mi (40.2 to 64.4 km) upstream of Lake Mead. A small tent city was erected along the Colorado River near Bridge Canyon, complete with "a tar-paper cook shack with tables, a walk-in refrigerator attached, and tents or sleeping accommodations for the men… a small generating plant which furnished lights and fans for the swamp-type air conditioners which were a necessity in this canyon." The site was only accessible by a 30 miles (48.3 km) boat trip up the Colorado River from Lake Mead, and was plagued by torrid heat, poor access, floods and long working hours.
After more than four potential damsites were investigated, the best one was found at a location called the "Lower Gneiss" site below the confluence of Gneiss Canyon, a small tributary, and 19 miles (30.6 km) northwest of the small town of Peach Springs
. The dam was proposed as a concrete arch-gravity structure 736 to 740 ft (224.3 to 225.6 m) high above its foundations, with a hydraulic head
from 666 to 672 ft (203 to 204.8 m). It would raise the water behind it for 93 miles (149.7 km) upstream to an elevation of 1876 feet (571.8 m) just below the mouth of Kanab Creek
.
The dam was also considered part of a massive proposal designed to bring Colorado River southwards out of the Grand Canyon into the Salt River
Valley in central Arizona known as the Central Arizona Project, the most expensive single project constructed by the Bureau of Reclamation. Along with Marble Canyon Dam further upstream, it would generate a portion of the massive power required to pump-lift the Colorado River five thousand feet out of the Grand Canyon. From there, the water would flow via a gravity canal south towards Arizona's primary agricultural regions in the Salt and Gila River
valleys.
, as well as an outcry from recreation-minded general public. The reason for this was because the dam would back water up for 13 miles (20.9 km) into Grand Canyon National Park, and 40 miles (64.4 km) through Grand Canyon National Monument. The resistance was strengthened by previous controversies pertaining to the construction of dams in national parks, such as the O'Shaughnessy Dam
in Yosemite National Park
which was built in 1925.
All of the proposals thus far for the dam have failed for one reason or another. In 1938, the state of Arizona attempted to gain federal permission to build the dam. Again in 1950, a bill was introduced in Congress for a Bridge Canyon Dam that would serve the water diversion purposes of the CAP. This time, it was not activists who killed it but rather representatives from California
in the United States House of Representatives
. This was because California did not want Arizona's utilization of its share of the Colorado River to increase, which would mean possible shortfall of water supplies in that state.
Even though the hypothetical dam and its reservoir lie along a remote, seldom seen or visited reach of the Colorado River, it would still destroy many well-known landmarks and points of interest. These include lower Havasu Creek, famed for its travertine formations and waterfalls, and Lava Falls, one of the most spectacular rapids on the Colorado. Opponents state that the meager storage capacity of the dam, as well as its potential to evaporate more than 85000 acre.ft of water per year, do not justify the dam's destruction of natural features and disruption to both the river ecology and recreational activities.
Because of the high silt load of the Colorado, the Bridge Canyon Reservoir would eventually fill with sediment, rendering it useless. Estimates by the Sierra Club suggest a useful life span of 60–160 years, while the Bureau of Reclamation predicts 163 years. Reclamation suggested building additional dams on Kanab Creek, the Little Colorado River
and Paria River
to act as silt traps in order to prolong the life span up to 250 years. These proposals, however, were not enough to save the dam. As a result, the Bridge Canyon project officially stalled in 1984.
Grand Canyon
The Grand Canyon is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona. It is largely contained within the Grand Canyon National Park, the 15th national park in the United States...
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 northern Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. It would be located near Bridge Canyon Rapids in an extremely rugged and isolated portion of the canyon, roughly 235 miles (378.2 km) downstream of Lee's Ferry
Lee's Ferry
Lee's Ferry is a site on the Colorado River in Coconino County, Arizona, United States, about 7.5 miles southwest of the town of Page, Arizona and the Glen Canyon Dam, and about 9 mi south of the Utah-Arizona border. It is the former location of a ferry established by John D. Lee, a Mormon...
and 30 miles (48.3 km) upstream of the current extent of Lake Mead
Lake Mead
Lake Mead is the largest reservoir in the United States. It is located on the Colorado River about southeast of Las Vegas, Nevada, in the states of Nevada and Arizona. Formed by water impounded by the Hoover Dam, it extends behind the dam, holding approximately of water.-History:The lake was...
.
The project was considered seriously by the U.S. Bureau of Reclamation for a period of over twenty years from the early 1950s to 1968. If built, the dam would tower 740 feet (225.6 m) high, forming a reservoir stretching more than ninety miles (150 km) upstream, including thirteen miles (21 km) inside Grand Canyon National Park
Grand Canyon National Park
Grand Canyon National Park is the United States' 15th oldest national park and is located in Arizona. Within the park lies the Grand Canyon, a gorge of the Colorado River, considered to be one of the Wonders of the World. The park covers of unincorporated area in Coconino and Mohave counties.Most...
. The dam would serve mainly for hydropower production and sediment retention in conjunction with several others further upstream including Marble Canyon Dam, on the Colorado, Green and other rivers.
Due to its enormous potential for environmental destruction and the dwindling flows of the Colorado River, the project stalled in 1968 after years of public opposition. However, the location is considered one of the best remaining sites for a large dam in the western United States.
Background
The Colorado River has one of the steepest gradients among major rivers in the United States in relation with its flow. In the late 1800s and the early part of the 1900s, the river's annual discharge exceeded 22000 cuft/s. From Glen Canyon to the mouth of the Grand Canyon (Lower Granite Gorge) near present-day Lake Mead, the Colorado drops a total of 1950 feet (594.4 m), giving it tremendous potential for hydroelectricity generation.Bridge Canyon Dam was first seriously considered in the 1940s as part of the Bureau of Reclamation's cascade of high power dams along the Colorado River system. Up to seven dams were proposed on the Colorado River alone, including Hoover
Hoover Dam
Hoover Dam, once known as Boulder Dam, is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the US states of Arizona and Nevada. It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President...
, Bridge Canyon, Marble Canyon (Redwall) and Glen Canyon
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...
, and perhaps an additional one or two within Grand Canyon National Park. However, only Hoover and Glen Canyon were eventually built, as well as several others on tributaries.
In the 1940s, Reclamation began investigating potential sites for a dam in the lower Grand Canyon near the river's confluence with Diamond Creek, 25 to 40 mi (40.2 to 64.4 km) upstream of Lake Mead. A small tent city was erected along the Colorado River near Bridge Canyon, complete with "a tar-paper cook shack with tables, a walk-in refrigerator attached, and tents or sleeping accommodations for the men… a small generating plant which furnished lights and fans for the swamp-type air conditioners which were a necessity in this canyon." The site was only accessible by a 30 miles (48.3 km) boat trip up the Colorado River from Lake Mead, and was plagued by torrid heat, poor access, floods and long working hours.
After more than four potential damsites were investigated, the best one was found at a location called the "Lower Gneiss" site below the confluence of Gneiss Canyon, a small tributary, and 19 miles (30.6 km) northwest of the small town of Peach Springs
Peach Springs, Arizona
Peach Springs is a census-designated place in Mohave County, Arizona, United States. The population was 600 at the 2000 census. Peach Springs serves as the administrative headquarters of the Hualapai people, and is located on the Hualapai Reservation.-Geography:Peach Springs is located at ...
. The dam was proposed as a concrete arch-gravity structure 736 to 740 ft (224.3 to 225.6 m) high above its foundations, with a hydraulic head
Hydraulic head
Hydraulic head or piezometric head is a specific measurement of water pressure above a geodetic datum. It is usually measured as a water surface elevation, expressed in units of length, at the entrance of a piezometer...
from 666 to 672 ft (203 to 204.8 m). It would raise the water behind it for 93 miles (149.7 km) upstream to an elevation of 1876 feet (571.8 m) just below the mouth of Kanab Creek
Kanab Creek
Kanab Creek is one of the many tributaries of the Grand Canyon. It begins in Kane County, Utah, just south of the watershed to the Great Basin and flows south to the Colorado River. It passes Kanab, Utah, crossing the border to Arizona near Fredonia...
.
The dam was also considered part of a massive proposal designed to bring Colorado River southwards out of the Grand Canyon into the Salt River
Salt River (Arizona)
The Salt River is a stream in the U.S. state of Arizona. It is the largest tributary of the Gila River. The river is about long. Its drainage basin is about large. The longest of the Salt River's many tributaries is the Verde River...
Valley in central Arizona known as the Central Arizona Project, the most expensive single project constructed by the Bureau of Reclamation. Along with Marble Canyon Dam further upstream, it would generate a portion of the massive power required to pump-lift the Colorado River five thousand feet out of the Grand Canyon. From there, the water would flow via a gravity canal south towards Arizona's primary agricultural regions in the Salt and Gila River
Gila River
The Gila River is a tributary of the Colorado River, 650 miles long, in the southwestern states of New Mexico and Arizona.-Description:...
valleys.
Defeat
After proposals for the dam surfaced, they met with almost immediate opposition from environmental groups such as the Sierra ClubSierra 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...
, as well as an outcry from recreation-minded general public. The reason for this was because the dam would back water up for 13 miles (20.9 km) into Grand Canyon National Park, and 40 miles (64.4 km) through Grand Canyon National Monument. The resistance was strengthened by previous controversies pertaining to the construction of dams in national parks, such as the O'Shaughnessy Dam
O'Shaughnessy Dam
The O'Shaughnessy Dam is a curved gravity dam on the Tuolumne River in the Hetch Hetchy Valley of California's Sierra Nevada. The dam is located in Yosemite National Park, and creates the Hetch Hetchy Reservoir. It is named for former San Francisco chief engineer and the original chief engineer of...
in Yosemite National Park
Yosemite National Park
Yosemite National Park is a United States National Park spanning eastern portions of Tuolumne, Mariposa and Madera counties in east central California, United States. The park covers an area of and reaches across the western slopes of the Sierra Nevada mountain chain...
which was built in 1925.
All of the proposals thus far for the dam have failed for one reason or another. In 1938, the state of Arizona attempted to gain federal permission to build the dam. Again in 1950, a bill was introduced in Congress for a Bridge Canyon Dam that would serve the water diversion purposes of the CAP. This time, it was not activists who killed it but rather representatives from California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
in the United States House of Representatives
United States House of Representatives
The United States House of Representatives is one of the two Houses of the United States Congress, the bicameral legislature which also includes the Senate.The composition and powers of the House are established in Article One of the Constitution...
. This was because California did not want Arizona's utilization of its share of the Colorado River to increase, which would mean possible shortfall of water supplies in that state.
Even though the hypothetical dam and its reservoir lie along a remote, seldom seen or visited reach of the Colorado River, it would still destroy many well-known landmarks and points of interest. These include lower Havasu Creek, famed for its travertine formations and waterfalls, and Lava Falls, one of the most spectacular rapids on the Colorado. Opponents state that the meager storage capacity of the dam, as well as its potential to evaporate more than 85000 acre.ft of water per year, do not justify the dam's destruction of natural features and disruption to both the river ecology and recreational activities.
Because of the high silt load of the Colorado, the Bridge Canyon Reservoir would eventually fill with sediment, rendering it useless. Estimates by the Sierra Club suggest a useful life span of 60–160 years, while the Bureau of Reclamation predicts 163 years. Reclamation suggested building additional dams on Kanab Creek, the Little Colorado River
Little Colorado River
The Little Colorado River is a river in the U.S. state of Arizona, providing the principal drainage from the Painted Desert region. Together with its major tributary, the Puerco River, it drains an area of about in eastern Arizona and western New Mexico...
and Paria River
Paria River
The Paria River is a tributary of the Colorado River, approximately long, in southern Utah and northern Arizona in the United States. It drains a rugged and arid region northwest of the Colorado, flowing through roadless slot canyons along part of its course....
to act as silt traps in order to prolong the life span up to 250 years. These proposals, however, were not enough to save the dam. As a result, the Bridge Canyon project officially stalled in 1984.