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Big Water: Will the Real Colorado River Please Rise Up?

A $4.5 million experiment unleashes a deluge of habitat-restoring froth
By Rob French

It will begin with the touch of a human finger. An engineer will press a red button deep inside Glen Canyon Dam. Hydraulic wedges will heave against the massive steel gate that holds back Lake Mead. Water will seep, and then spurt, through the opening valve. Minutes later and about 18 miles downstream, decades of riparian frustration will be unleashed on the Grand Canyon as the
Colorado River, swollen to twice its normal size, marauds through, rolling boulders as if they were Easter eggs and ripping trees from the banks. A week later, the river will be switched back to “low,” where it’s been since the dam was built in 1963.

What’s this roiling Armageddon all about? “Science,” beams Ted Melis, a hydrologist with the Bureau of Reclamation, which has authorized $4.5 million to flood the canyon beginning March 26. Out of character though it may seem for an agency that has spent 50 years and billions of dollars building dams and disrupting ecosystems, the bureau hopes to find out whether “supervised”
floods can help restore riparian habitats to pre-dam conditions. Specifically, will an extra 35,000 cubic feet per second of water drive off non-native fish species and replenish the river’s rapidly disappearing sand beaches, stomping grounds to dozens of native species? If the experiment works, the bureau says it may flood the river regularly in a sort of engineered mimicry of
nature’s own springtime floods.

Interestingly, the plan is drawing praise from both environmentalists and utility companies–the latter being paid for lost power production. But perhaps no one is more thrilled about the coming flood than a handful of Top-Gun-caliber whitewater rafters, who in the last few decades have grown accustomed to a kinder, gentler stream. “It’s hard to even predict what the water will
be like,” says Andre Potochnik, who’s guided on the Colorado for 23 years. “Big whirlpools and boils, waves crashing off the walls, waves that come out of nowhere.” Lava Falls, which routinely dunks rafters during “normal” conditions, is expected to become a roaring 18-foot breaker.

So who’ll get to go? The Grand Canyon River Guides Association has permission to hold its annual training program during the high waters. Otherwise, access will be tightly controlled–with amateurs strictly forbidden unless they’re part of a scientific team or booked on one of the seven scheduled raft trips.

“You won’t want to be out there if you don’t know what you’re doing,” says Potochnik. “We’re finally going to see the real Colorado River–not a shy imitation.”