Here’s an in-depth report about decommissioning Glen Canyon Dam from Krista Langlois writing for The High Country News. Click through and read the whole article. Here’s an excerpt:
For wilderness lovers, the 710-foot-tall concrete wall stuck out of the Colorado River like a middle finger — an insult that helped ignite the modern environmental movement. In 1981, the radical group Earth First! faked a “crack” on the dam by unfurling a 300-foot-long black banner down the structure’s front. The Sierra Club’s first executive director, David Brower, considered the dam’s construction a personal failure and spent the rest of his life advocating for its removal. And in his iconic novel The Monkey Wrench Gang, author Edward Abbey imagined a group of friends secretly plotting to blow up the dam and free the Colorado River.
In real life, though, Glen Canyon Dam and Lake Powell made it possible for millions of people to live and grow food in the arid Southwest. Together, the dam and the reservoir store precious snowmelt for year-round use, help generate electricity for 5.8 million homes, and enable states from the Upper Colorado River Basin to fulfill their legal obligation to deliver water to downstream states. Last year, the federal government underscored its support for the dam by finalizing a plan that will guide management for the next two decades.
Even so, an unprecedented interest in dam removals and the specter of climate change have created fresh hope for those who want to see the drowned canyon resurrected. From 1990 to 2010, the population of the American Southwest grew by 37 percent, even as the amount of water flowing into the Colorado River system shrank amid a historic drought. More people using fewer resources means that neither Lake Powell nor Lake Mead, the downstream reservoir created by Hoover Dam, have been full since 1999. And climate change promises to squeeze the water supply even further, with future droughts expected to bring even hotter and drier conditions.
Meanwhile, Lake Powell may be squandering the very resource it was designed to protect. Every day, water slowly seeps into the soft, porous sandstone beneath the reservoir and evaporates off its surface into the desert air. When more water flowed in the system, this hardly mattered. But in an era where “every drop counts,” says Eric Balken, executive director of the nonprofit Glen Canyon Institute, it calls for a drastic re-evaluation of the Colorado River’s plumbing. “The Colorado River can no longer sustain two huge reservoirs,” Balken says. “There isn’t enough water.”
That’s one reason the Glen Canyon Institute is pushing an audacious proposal called “Fill Mead First,” which calls for the U.S. Bureau of Reclamation to drain Lake Powell and send the water downstream to Lake Mead. In theory, combining two reservoirs into one would shrink their surface area, reducing the amount of water that’s lost to evaporation. It would also mitigate seepage, since Lake Mead is surrounded by hard volcanic rock rather than sandstone. The Colorado River would run freely through Glen Canyon and the Grand Canyon, but Glen Canyon Dam would stay in place to store water if cooler, wetter conditions return — a compromise of sorts.
Not long ago, the idea of breaching Glen Canyon Dam was laughably unrealistic. Since 1999, though, more than 850 dams have been removed from U.S. rivers, and ecological restorations that once seemed pie-in-the-sky are looking increasingly probable. There’s just one problem: The science behind Fill Mead First is as muddy as the Colorado River itself.