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Grand Canyon in deep trouble
It's hard to get the sense that anything is wrong in the Grand Canyon while floating it. On a recent spring morning, the Colorado River was cool and calm. Trout leapt, splashing back into the river with a loud plop. Stands of salt cedar trees lined the banks, offering shade from the desert heat. But all is not well in this crown of America's national park system. The salt cedar and trout are invaders, part of a wave of alien fish and plants that have moved in and devoured or crowded out the species. The sandy shorelines are washing away. And once-buried Indian archaeological sites are slipping the river. The Grand Canyon is in deep trouble, and the government-appointed panel assigned to come up with solutions is torn by competing interests and cannot muster the political will to act decisively. "The best that we can do is keep slapping on as many Band-Aides as we can and hope the patient survives,” complained Pam Hyde, one of two environmentalists on the panel.
The Colorado is a different river from one explored by the one-armed Civil War veteran John Wesley Powell, who in 1869 the first expedition through the Grand Canyon. The landscape and biology transformed by the Glen Canyon Dam, built upstream in 1963 to generate power and store water. Before the dam was erected the Colorado would fill with snowmelt and flood violently in the early summer, then dwindle to a trickle in the winter. The dam smoothed the flow. In Powell's day, the Colorado was warm and muddy. Now it runs cold and clear, because sediment gets caught behind the dam in Lake Powell and because the water released through the dam comes from the reservoir's lower, cooler depths.
Over the years, nearly $200 million assessing what the dam has done to the Grand Canyon and exploring what can be done to fix it. In an ambitious experiment to see whether Glen Canyon Dam can help solve the very problems it has created, the U.S. Geological Survey has unleashed floods, released short pulses of water and even simulated a summer drought to see if this build up the sandbars and restore the river in other respects. Also, lasers a
nd sonar map the canyon's loss of sand. Implanted microchips allow scientists to monitor endangered fish and follow the movements of boulders downstream. But an overall plan for saving the Grand Canyon has yet to emerge and much of the research merely confirms what scientists already know.