Officials Fear Arizona Dam Release Harmed Lake's Fish Species

Published: Tuesday, December 4, 2018 - 9:18am

Wildlife officials are working to figure out the impact of a release of more than 9 billion gallons of water from a dam in western Arizona.

The Arizona Department of Game and Fish conducted a study of the March water release from Alamo Dam months ago, and the results will be available early next year. Officials fear the worst for the lake's fish species, Today's News-Herald reported.

The release of water by the U.S. Army Corps of Engineers was needed to provide long-overdue maintenance to the 50-year-old dam, the agency said.

Chris Cantrell, fisheries manager with Game and Fish, said the release reduced Alamo Lake's elevation by 10 feet in about 20 days, which might have harmed fish in the reproductive stage.

"Most if not all current spawning areas and eggs may have been lost, leading to fewer young fish and declines in recruitment," Cantrell said. "Even if spawning nests remained submerged during the lake level declines, the changing lake environment may have caused largemouth bass or black crappie to abandon the spawning nests, making their eggs vulnerable to predators."

Cantrell said the lower lake levels also might have resulted in a loss of underwater vegetation that protects younger fish against predation.

Game and Fish sought unsuccessfully to stop the lake from being drained.

The Arizona Game and Fish Commission is scheduled to meet Friday to consider a memorandum of understanding between the department and the Army Corps, which is evaluating if operational changes are needed at the dam. The Army Corps held meetings earlier this year and is reviewing comments from anglers, environmentalists, utility companies and off-road vehicle enthusiasts.

The meeting will help inform future maintenance and drainage of the water in the dam, and keep the Game and Fish Department in the loop for any planned water releases.

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