Wild Salmon Migration and Hydropower Impacts

How hydropower dams impede wild salmon migration, the welfare consequences for individual fish, and mitigation approaches including fish passage technology.

Key Facts

Salmon have declined dramatically in rivers with impassable dams that block migration routes
Migrating salmon may travel thousands of kilometres and face multiple dam barriers in a single migration
Fish ladders and other passage structures vary enormously in effectiveness for different species and life stages
Turbine mortality affects downstream migrating juveniles — smolts may be killed or injured passing through turbines
Dam removal has produced rapid and dramatic salmon population recovery in multiple river systems

Welfare Considerations

Dam barriers create welfare harms for individual salmon at multiple life stages — adults unable to reach spawning grounds, juveniles injured or killed passing through turbines, and fish expending enormous energy attempting to ascend impassable barriers. The welfare dimension complements the conservation concern: individual fish experience genuine suffering during failed migration attempts. Fish passage technology can mitigate but not eliminate these harms. Dam removal, where feasible, offers the most complete welfare and conservation solution by restoring natural migration corridors.

What You Can Do

Support dam removal campaigns on rivers where salmon populations could benefit from restored passage
Advocate for effective fish passage requirements as conditions of hydropower licensing renewals
Donate to organisations working on river restoration and fish passage improvement projects
Choose electricity providers committed to hydropower practices that minimise impacts on migratory fish
Learn about fish passage science and engage with river management decisions in your region