March 5, 2008—It's the little Dutch boy's worst nightmare.

Three hundred thousand gallons (1,135,623 liters) of water per second gush from Arizona's Glen Canyon Dam during a media event on Wednesday—enough to fill the Empire State Building in 20 minutes, U.S. Interior Secretary Dick Kempthorne said.

The gathering trumpeted a three-day controlled flood that is designed to help restore Colorado River habitats for endangered species in the Grand Canyon, U.S. Department of the Interior officials say.

Completed in 1963, the dam did away with the river's natural spring floods and generally caused the water to become cooler and clearer, sending some native fish species to extinction.

This week's torrent should temporarily raise the river a few feet and stir up sediments, thereby restoring sandbars and side pools needed by at-risk fish and plant species—as well as beaches beloved by rafters.

But not everyone is going with the flow.

Grand Canyon National Park Superintendent Steve Martin told the Los Angeles Times he was given only a day to review an environmental assessment of the project.

He added that additional flooding was needed and that the timing was designed to please hydroelectric power producers, whose turbines see less action when a large volume of water from behind the dam is released into the Colorado River.

—Ted Chamberlain

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