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
This article appeared in the print edition of the magazine with the headline Not such a cold fish.
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