Glen Canyon Dam
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Glen Canyon Dam is a dam on the Colorado River at Page, Arizona. The dam has been controversial since its inception, because it caused the flooding of Glen Canyon to create a man-made reservoir, Lake Powell.
The dam is 1,560 feet long along its crest, 300 feet thick at the base and 25 feet thick at the top. Its height above the Colorado River is 587 feet. Eight Francis type hydroelectric generators give it a generating capacity of 1,300 Mw.
Its construction began in 1956. Although the dam was not dedicated until 1966, it was able to begin blocking the flow of the river in 1963.
The Sierra Club and other environmental organizations opposed the original plan for damming the Colorado River. When the plan was modified by the elimination of other proposed dams, however, the Sierra Club dropped its objection to the Glen Canyon Dam. Its then Executive Director, David R. Brower, later called this decision one of the biggest mistakes of his career:
- "Glen Canyon died, and I was partly responsible for its needless death. Neither you nor I, nor anyone else, knew it well enough to insist that at all costs it should endure. When we began to find out it was too late."
(From The Place No One Knew, a Sierra Club book published in 1963)
The dam has continued to attract opposition. In the novel The Monkey Wrench Gang, by Edward Abbey, the protagonists believe strongly that the dam has ruined the river. Since 1996, the Sierra Club has called for increasing the release of water, so that a more natural flow of the river is restored and Lake Powell is gradually drained.
Owing to this dam, there had not been the periodic flooding that would wash away and renew sand banks along that portion of the Colorado River that transited the Grand Canyon. Because of the stability of the sand banks, several non-native species of plants became established, adversely affecting the native wildlife. These problems have been recently addressed by the experimental periodic releases of large amounts of water, which appear to have had a beneficial effect upon the downstream ecosystem.
Colorado_River_below_the_Glen_Canyon_Dam.jpg
External links
- Glen Canyon Dam National Recreation Area (http://www.nps.gov/glca/damindx.htm)
- Glen Canyon Dam page from the Bureau of Reclamation (http://www.usbr.gov/dataweb/dams/az10307.htm)
- Images of Glen Canyon before it was flooded (http://www.lib.utah.edu/spc/photo/crampton/crampton2.htm)
- Article by David Brower on restoring Glen Canyon (http://www.sierraclub.org/sierra/199703/brower.asp)
- The Glen Canyon Institute (http://www.glencanyon.org)
- Glen Canyon Dam on Google Maps (http://maps.google.com/maps?ll=36.936089,-111.483775&spn=0.008894,0.009356&t=k&hl=en)