Visitors to the majestic Grand Canyon next year may get to see something that has happened only a few times in the past half-century.
The Colorado River, restrained in its flow through the canyon since the 1960s, will be allowed to gush in semi-flood conditions again, beginning next year under an Interior Department plan to protect native fish and naturalize the river.
Interior Secretary Ken Salazar said the decision to conduct high-volume releases from Glen Canyon Dam, which has drawn concern from the power industry and Native American tribes, represents "a milestone in the history of the Colorado River" that will enhance conservation and scientific knowledge. Simulated floods in the canyon are planned through 2020.
Leslie James, executive director of the Colorado River Energy Distributors Association, a non-profit coalition of electric companies, said she has "serious concerns" about the high-flow protocols: "I think the devil's in the details of how it will be implemented."
James said the release of surge water through spillways - bypassing hydroelectric turbines - is expected to cost power companies $8 million to $120 million over the next eight years. She said there is scientific evidence that surges from the dam during spring runoff might produce huge spawns of trout, the primary predator of the native humpback chub. "I think it raises a lot of questions," James said.
The first controlled flood could occur next spring. Interior Department protocols call for releases of up to 45,000 cubic feet per second during March-April and October-November, each lasting up to four days.
Until the Colorado River was dammed in the 1960s, it flowed through the Southwest, especially during flood seasons, when it carried sediment that formed sandbars and created eddies critical to native fish such as the humpback chub. Completion of Glen Canyon Dam in 1966 allowed regulation of the river's flow for hydroelectric production but eliminated natural beaches and created a haven for predatory species such as rainbow trout.
Environmentalists always argued the dam should be opened occasionally to emulate the Colorado River's naturally occurring floods. Power industry officials resisted, saying lost hydroelectricity production would cost consumers millions of dollars.
Salazar said his decision was based on results from high-flow tests conducted in 1996, 2004 and 2008.
Nikolai Lash, a program director with the Grand Canyon Trust, a conservation organization, said man-made floods may help save a devastated river. "They're especially critical now because the Colorado system is in a severely depleted state," he said.
Kurt Dongoske, historic preservation officer for the Pueblo of Zuni, said the tribe will watch closely out of concern that artificial floods may damage religious sites.
The National Park Service issued a notice that says river rafters will be advised when high flows are planned. Rafters may travel at double the normal speed, and some camp areas may be inundated. Jonathan Jarvis, director of the National Park Service, said the research will be critical to preserving the Grand Canyon's "awesome resources and visitor experience."
By Dennis Wagner