Does research suggest that removing dams on the Snake River could help revive fish populations?

Dams disrupt the migration patterns of salmon and steelhead born in fresh water that travel downstream to live their adult lives in the ocean before returning upstream to lay their eggs. Dams block their paths, slow water flow and raise water temperatures, attracting predators.

In February, 2021, 68 fisheries researchers from the Pacific Northwest called for the removal of four federally-operated dams along the Snake River in southeastern Washington, citing research about survival rates for salmon as the number of dams in their path increases. Regional political leaders disagree about the best way to proceed.

Yale Environment 360 reported in 2019 that the dams “are prime targets for removal because their economic value has diminished and their absence would inordinately benefit salmon.” Other energy sources have undercut hydroelectric power in the region, and freight volume on the river has declined 70%, Yale noted. A 2017 study cited by Yale estimated as much as a threefold increase in the area’s salmon population were the dams to be removed.