For one week this spring, the Colorado River will
rage through the Grand Canyon much as it did before Glen Canyon Dam
tamed its flow. The remedy for the canyon’s eroding beaches and
silted backwaters was recommended in the 1995 Glen Canyon Dam
Environmental Impact Statement.
“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
This article appeared in the print edition of the magazine with the headline For seven days, it will flood.
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