Same Dam Story

Lake Powell's high waters are flushing the Grand Canyon again. Is it Mother Nature's fault or the Bureau of Reclamation's?

Through May and June, as the late-spring melt flooded into Lake Powell, scientists, environmentalists and river runners all wondered aloud if the water level would reach the top of the Glen Canyon Dam spillway gates, which serve about the same purpose as the overflow drain on a bathroom sink.

Everyone but Bureau of Reclamation staffers was thinking back to 1983, when Reclamation had to open those gates to keep the lake from going over the top of the dam; the resultant flow broke through the spillway walls into the canyon sandstone, jeopardizing the dam and everything downstream.

This year Reclamation had gauged--or gambled--that the water would peak just four or five feet shy of the top, that it wouldn't even have to open the dam's "jet tubes," those big pipes in the spectacular TV footage of March 1996, when Interior Secretary Bruce Babbitt flipped a switch to start the controlled flood that "fixed" the Grand Canyon. Reclamation hates to open the tubes because they bypass the power-plant turbines, spilling water that otherwise might have generated electricity.

Babbitt's deluge last spring helped rebuild the eroded sand beaches of the canyon. Sediment that had come into the river from the streams and rivers that run into it was scoured up and redeposited on the sides of the canyon. It was a final experiment in a decade's worth of research that resulted in a new plan to run the Glen Canyon Dam, a plan that was supposed to be less damaging to the Grand Canyon.

However, because the lake is so high now, Reclamation will have to release heavier water flows than called for in the new plan all through the summer and again next spring to avoid catastrophe next year. The turbines will run at full throttle, generating watts and profits. The beaches will wash away.

And the scientists and environmentalists, dredging up years of experience and cynicism, assume that just as the Colorado River relentlessly flows and erodes the canyon, so does Reclamation's old way of doing business.

"The record of decision [which came out of the Environmental Impact Statement] that was signed into law basically said we will start to manage Lake Powell and Glen Canyon Dam differently to minimize the effect on the environmental resources downstream," says Dave Wegner, who headed Reclamation's research in the Grand Canyon until he was mysteriously transferred and subsequently quit at the end of last year ("Water Over the Dam," March 27). "But they followed the exact same mandates they have always followed, which is water and power come first. So the risk is still on the environmental resources."

Ironically, at a time when David Brower, the former Sierra Club archdruid, and Wegner, the Canyon's most experienced scientist, are calling to drain Lake Powell altogether, Reclamation has allowed it to fill to the brim.

When the Environmental Impact Statement was written in 1995, Lake Powell was so low that the document's authors at Reclamation speculated that it would take four or five years to "reach full elevation." That time cushion would allow the bureau to contemplate flood-control measures, such as raising the height of the spillway doors.

It took less than two years for the lake to fill.
"Right now they're pushing the levels at all of the dams," says Dave Hogan of the Southwest Center for Biological Diversity. "I think they'll wait until it's a crisis."

The Southwest Center filed suit against Reclamation in April over the levels of Lake Mead, just on the other side of the Grand Canyon from Lake Powell. The suit alleges that the high water was drowning habitat for the endangered Southwestern willow flycatcher.

Rob Smith of the Sierra Club, like Wegner, speculates that the high levels are "for the sake of the water and power interests, to make sure Lake Powell is as full as it can be."

Mark Manone, a geologist at Northern Arizona University who has researched the sediment levels in the Grand Canyon in the ongoing studies there, adds, "My personal opinion is, yes, absolutely, they keep it high just so they can go around [the rules]. It's one way for the dam to reclaim control."

But in reality, Reclamation doesn't need a full lake to generate electricity, nor a full basin to meet water demand.

"I would have thought they would have been more informed," Reclamation's Randy Peterson says of the Bureau's critics. "We don't have the option of releasing half the lake under current statutes. We can only release water in three situations: to avoid spills, to equalize water levels in Lake Mead, and to meet water demand."

The high levels, Peterson says, are the plain and simple result of high run-off years. And there have been worse years.

In June of 1983, Lake Powell rose to within four feet of the top of the spillway gates with plenty of water still raging into the lake from the Colorado River, and Reclamation opened the gates.

The spillways are long tunnels drilled through the sandstone canyon walls on either side of the dam. They were originally built to temporarily route the river around the dam construction site, then were kept as emergency drains. Four days after they were opened in 1983, dam workers saw giant chunks of concrete and stone flushing out the bottom of the spillway tunnels into the river, which meant that the rushing water had broken through the spillway walls and was washing away the rock at the base of the dam, threatening its very foundations. The spillway was shut, and after several shaky days, a crisis averted.

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