Lake Powell is a tourist mecca, drawing some three million visitors a year for its watersports and spectacular scenery. But it wasn't always this way: forty years ago, Glen Canyon was mostly dry, with the Colorado River cutting a path on the canyon floor. Lake Powell didn't even exist.

The flooding of Glen Canyon was a result of the construction of Glen Canyon Dam in 1963. Standing 710 feet tall, the broad, thick dam impedes the progress of the Colorado River as it travels from the Rocky Mountains to the Gulf of California. The dam was constructed to generate electricity and to create a reservoir, Lake Powell, for irrigation. It took 17 years for the canyons to flood and for Lake Powell to reach its maximum depth. Today, narrow canyons that could once only be reached by hiking can be accessed with a lazy cruise on a houseboat.

While navigating the canyons by boat makes for a fun holiday, many people mourn the loss of Glen Canyon to water. They also say that the price the dam exacts on the river itself is too high.

So, the debate is not over whether the dam has changed the complex river habitat and the canyons. The debate is over whether the changes are for better or for worse.

"The Place No One Knew"
David Brower spent some 40 years agonizing over Glen Canyon. "Glen Canyon died, and I was partly responsible for its needless death," Brower wrote in the book The Place No One Knew, published in 1963. Brower was the executive director of the Sierra Club, one of the United States' major environmental organizations, when Glen Canyon Dam was constructed. At the time, he voted "yes" to the project, despite the fact that he had serious worries about its potential impact. Over 30 years later, in his 1997 essay "Let the River Run Through It," Brower wrote, "I have worn sackcloth and ashes ever since, convinced that I could have saved the place if I simply got off my duff."

Brower, a leading environmentalist, died in 2000. Part of his legacy is that the Sierra Club now supports his motion to decommission the dam. It says that draining Lake Powell would have the dual benefits of restoring Glen Canyon and a huge section of the Colorado River's ecosystem to their former states; in addition, it would give the river back some of the power it has lost due to dam-controlled flows. "The river has become a stream that can barely continue carving the Grand Canyon," the Club's Colorado River Task Force says.

Before his death, Brower wrote eloquently about bringing "lost paradises" back by draining Lake Powell. He longed for Glen Canyon's natural formations — such as desert varnish — to be revealed again; for the river to snake along the canyon floor at its own pace; for the return of plant and animal species that have been "exiled" by the lake; for the pictographs etched by early settlers to be revealed once more. "The canyon's music will be known again," he said.

Should the dam be torn down? Brower didn't think so. Instead, he suggested opening up its gates to allow water and silt to come through as nature dictates. "The dam itself would be left as a tourist attraction, like the Pyramids, with passers-by wondering how humanity ever built it, and why."

But what of the energy that the dam supplies and the water drawn from the lake for agriculture? According to Brower, when it comes to electricity, Lake Mead's Hoover Dam can pick up the slack. And Lake Powell actually loses so much water each year — up to one million acre-feet, worth as much as $1 billion — that it is not a viable reservoir. "Hoover Dam can control the Colorado River without Lake Powell and can produce more power if Powell's water is stored behind it — saving massive amounts of money, water, and wild habitat. Economics and ecology are ready to team up on this one."

For every argument Brower, the Sierra Club, and others make in favor of draining Lake Powell, FOLP has a response. For instance, it says that Lake Powell's water loss is minimal in comparison with its actual volume. It also applauds Glen Canyon Dam for relatively "clean" power generation — compared with, say, a coal-fired power station.

But perhaps the most compelling argument in favor of keeping Lake Powell intact is the economic one. Page has grown because of Lake Powell. The annual influx of three million tourists — most of whom indulge in watersports — is the very livelihood of Page's 9,000 citizens. FOLP says that "current lake-based recreational activities contribute an estimated $400 million into the local economy each year." It's likely that this income would be drastically reduced if the lake were drained.

FOLP also claims that the government would lose millions of dollars in electricity revenue if the dam were decommissioned. On top of that, the profitable Navajo Generating Station, a steam-driven power station that relies on water from Lake Powell, would have to be shut down. In all, FOLP says, "countless jobs would be lost and local property values would plummet. In the end, the tremendous economic cost of draining Lake Powell would fall squarely on the shoulders of the American taxpayer."

For now, the American taxpayer need not worry about footing the bill: the government has no plans to decommission Glen Canyon Dam or to drain Lake Powell.

• Which argument do you think is more valid — that of the Sierra Club or of Friends of Lake Powell? Or do you think that each side has a good case? You can learn more about each side's perspective from their Web sites.
• You can also visit the Web site of the Glen Canyon Institute which campaigns to drain Lake Powell. The site contains many interesting essays and interviews on the debate.
• Some interesting projects are going on downriver from Glen Canyon Dam, where scientists are trying to repair the Colorado River's damaged ecosystem. They are running experiments and plan to put warmer, siltier water through the dam with the aim of reviving native fish populations and rebuilding beaches along the river banks. They also want to decrease the numbers of nonnative trout which are in abundance in the cold, silt-free water. The method is called "adaptive management." Learn more from the Adaptive Management Work Group's Web site and "Canyon flooding could restore beaches," an article from The Arizona Republic.
• The balance among fish species downriver has been upset by the dam. Five native species are on the endangered list; it's thought that nonnative trout might actually be eating some of the native fish, such as the humpback chub. You can learn more about the balance among species in an ecosystem — and what happens when the balance is upset — in our series of science simulations, Exploring Populations.
• Read about David Brower's legacy in the CNN article, "Environmentalist David Brower dead at 88."
• This article features many quotes from David Brower's essay, "Let the River Run Through It." You can read the complete essay on the Sierra Club's Web site.