Science Fair Project Encyclopedia
Glen Canyon Dam
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.
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.
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details