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Federal appeals court OKs boosting water spill to aid salmon, steelhead at Northwest dams

UMATILLA, OREGON - JUNE 7: A Chinook salmon passes through the viewing room at McNary Lock and Dam on the Columbia River, June 7, 2005 near Umatilla, Oregon. In late May 2005, a federal judge in Portland, Oregon rejected the Bush administration's $6 billion plan to improve dams on the lower Snake River and Columbia River ruling it failed to protect threatened and endangered salmon under the Endangered Species Act. An estimated 53,000 chinook salmon have passed through the two fish ladders at McNary to date in 2005. (Photo by Jeff T. Green/Getty Images)

PORTLAND, Ore. (AP) — A U.S. appeals court on Monday affirmed an order to spill more water over Columbia and Snake river dams to help protect salmon and steelhead and aid their migration to the sea.

The decision came after U.S. District Court Judge Michael Simon of Oregon ruled last spring that the U.S. Army Corps of Engineers must spill more water through spillways rather than turbines that pose a danger to the fish.

He sided with conservationists who say allowing extra water to flow between April and mid-June will help young salmon.

The Army Corps, National Marine Fisheries Service and another federal agency appealed Simon’s ruling.

A three-judge panel of the 9th U.S. Circuit Court of Appeals said Monday that Simon rightly concluded that the salmon and steelhead are imperiled and will remain so without further conservation efforts.

The judges also pointed to decades of studies that show higher spill volumes lead to increased survival rates.

“At best, federal defendants establish uncertainty about the benefits of increased spill, but the existence of scientific uncertainty does not render the district court’s findings clearly erroneous,” Chief Judge Sidney Thomas wrote in the opinion.

The new spill operations are set to begin Tuesday at some dams on the Snake River and next week on some dams in the Columbia, one of the largest rivers in North America. The Snake is its largest tributary.

Conservation groups said it’s the fourth time since 2005 that increased spill has been mandated by the district court.

“It’s tragic that the federal agencies are still ignoring their own science in fighting spill at every step of the way,” said Glen Spain, Northwest regional director of the Pacific Coast Federation of Fishermen’s Associations.

The corps did not have an immediate statement on the ruling. Agency spokesman Tom Conning said it may respond later in the day.