Judge Orders Dam Adjustments to Aid Salmon Migration

A federal judge in Portland, Oregon, ordered limited adjustments to operations at hydropower dams on the Columbia and Snake rivers late Wednesday, aiming to protect declining salmon populations in the Pacific Northwest. The ruling rejected the federal government's proposed changes, which the judge said would endanger migrating fish runs already vanishing from the region.

U.S. District Judge Michael Simon issued the preliminary injunction in response to a lawsuit brought by the state of Oregon, along with conservation groups, fishing organizations and Native American tribes. The plaintiffs argued that the dams kill large numbers of salmon as the fish navigate through turbines and reservoirs during their migration. Supporting the case as friends of the court were Washington state, the Nez Perce Tribe and the Yakama Nation.

The dispute centered on reservoir water levels and spill volumes over the dams. The plaintiffs sought lower reservoir levels to speed fish passage and higher spill amounts to allow more salmon to bypass turbines by traveling over the structures. Federal officials, representing the Trump administration, requested higher reservoir levels to support power...