Salmon rely on cold water. On the Columbia and Snake rivers, dams and climate change create lethal conditions for key species.
Conditions
Dams on the Columbia and Lower Snake Rivers create large, stagnant reservoirs that soak up the sun’s energy, making the water too hot for salmon. Climate change makes this bad situation even worse.
Scientists predict that heat pollution will cause the extinction of Snake River sockeye and other salmon runs—unless we address how the dams warm the Columbia and Snake rivers. Without the four dams, the Lower Snake River would stay cool enough for most sockeye salmon to migrate safely, even in very hot years.
About the Issue
Narrated by Don Sampson of Northwest Tribal Salmon Alliance: “The sockeye here are dying. They are suffocating. You can see they are in lethally hot water. We’re in a salmon crisis and it’s time for Congress to act.” (Video produced by Modoc Stories.)
Columbia Riverkeeper Fights for Cold Water
For over a decade, Columbia Riverkeeper has used science and the Clean Water Act to ratchet up pressure on the U.S. Army Corps of Engineers (Corps) to reduce heat pollution caused by its dams.
A quick history of this issue:
- 2014: Columbia Riverkeeper sues the Corps for discharging oil and heat pollution into the Lower Snake River without Clean Water Act Permits.
- 2015: 96% of adult endangered Snake River sockeye salmon die because of hot water in the Lower Snake and Columbia rivers. Major temperature-related fish kills occur in the summers of 2013, 2021, and 2023.
- 2016: Columbia Riverkeeper and allies sue under the Clean Water Act to require EPA to create a pollution budget (called a Total Maximum Daily Load analysis, or TMDL) for heat pollution in the Columbia and Lower Snake rivers.
- 2017: Columbia Riverkeeper uses computer modeling to show that, without the dams, the Lower Snake River would be cool enough for salmon to migrate safely.
- 2019: Ninth Circuit Court of Appeals sides with Columbia Riverkeeper and allies, and orders EPA to write a temperature TMDL for the Lower Snake and Columbia Rivers.
- 2021: EPA releases a final temperature TMDL for the Lower Snake and Columbia rivers. The TMDL identifies the dams and reservoirs as major sources of heat pollution, and sets numeric temperature reduction targets for each dam.
- 2022: As a result of Columbia Riverkeeper’s original suit against the Corps, EPA finally issues Clean Water Act discharge permits for the Corps’ Lower Snake River dams. These permits require the Corps to make a plan (called a Water Quality Attainment Plan) to achieve the temperature reductions mandated by the TMDL.
- 2025: The Corps and the Washington Department of Ecology will study potential actions—like drawing down reservoir levels for part or all of the year—to keep the water cool enough for salmon.
