For seven days, it will flood
"The ecosystem of the Grand Canyon is based on disturbance," says Tom Moody, a former river guide who now works for the Grand Canyon Trust. Historically, silt-heavy flows "ripped the beaches out" and created new ones. But ever since Glen Canyon Dam was built in the 1960s, river sediment has been trapped behind the concrete barrier.
The Bureau of Reclamation expects the controlled flood, which begins March 27, to clear closed backwaters favored by the endangered humpback chub. River sandbars and camping beaches, which buffer archaeological sites from the river's current, will also benefit from the 2 to 4 feet of new sand the flood will leave behind.
Environmentalists have been pressing the Bureau of Reclamation for five years to let the river rip, but opposition from hydropower interests delayed action. Now, there's a compromise, says Wayne Cook, executive director of the Upper Colorado River Commission. After this year's experimental flow, future releases will occur only when Lake Powell is high enough to spill on its own. But if this release is successful, environmentalists hope the BuRec will send the floodwaters through the canyon about every 10 years.
* Dustin Solberg