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Know the West

Not such a cold fish

  When the Endangered Species Act was signed 25 years ago, one of the first species to gain protection was the humpback chub. The chub, a warm-water fish native to the Colorado River system, has been headed downhill since 1967, when the construction of Glen Canyon Dam near the Arizona-Utah border cooled the downstream section of the river.


Now, after years of prodding from the Fish and Wildlife Service, the Bureau of Reclamation is proposing to make the Colorado River more hospitable to the chub. Modifications to a set of intake pipes on Glen Canyon Dam would draw water from a higher level in the reservoir, sending warmer water downstream.


"We think we've got a pretty good product," says Barry Wirth, spokesman for the Bureau. He says the $15 million modifications would raise the water temperature by about 13 degrees, making the river more tolerable for both the chub and the non-native rainbow trout.


Some researchers are more cautious. "The concept is good, but (the agency's) implementation is poor," says Joseph Shannon, an aquatic biologist with the Grand Canyon Monitoring and Research Center, a publicly funded research agency in Flagstaff, Ariz. He points out that the modifications will only be in operation for 30 days each year, and will be shut down completely if there's a drought. "They think that's good enough," he says. "It just isn't logical."


David Orr, a board member of the Glen Canyon Institute, a nonprofit group studying the possibility of draining Lake Powell, also says the changes are a case of too little, too late. "This is not a really serious effort to address the very serious effects that Glen Canyon Dam has on the river," he says.


The Bureau of Reclamation has released an environmental assessment on the proposed modifications, and is accepting public comments on the plan until the end of March. The agency hopes the changes will be in place by 2002.


*Michelle Nijhuis