The ruling requires federal stakeholders to rework the 2004 Biological Opinion that outlines the ecological rationale for the $600 million per year proposed to protect 13 threatened salmon species. The National Oceanic and Atmospheric Administration’s Marine Fisheries Service, along with other federal agencies, asserted that protection proposals could ignore dam operations because their permanence placed them beyond regulatory purview, much as a waterfall would be exempt. The May 26 ruling by Judge James Redden of U.S. District Court in Portland, Ore., called the interpretation legally flawed and inconsistent with ESA precedent.

The ruling does not immediately affect hydroelectric operations. The environmental consortium’s lawsuit is aimed at temporarily suspending operations and spilling water through the dams to improve survival of juvenile salmon during the downstream summer migration.

"If the plaintiffs’ motion were granted by the court, we expect the cost of this year’s operation for our system would go up over $100 million," said Bonneville Power Administration Administrator Steve Wright, Portland. The 14 dams subject to the ruling generate 19,690 MW of BPA’s total of 20,444 MW of hydroelectric power.

The U.S. District Court has set a hearing for June 10 in Portland on the latest suit.

n environmental consortium has filed suit to change operations at eight dams following a federal court ruling that the 14 dams of the Federal Columbia River Power System are not immutable features of the landscape and federal agencies are required by the Endangered Species Act to mitigate the impact on salmon.