Why did environmental groups call for removal of dams on the lower Snake River?

Environmental groups have advocated for the removal of dams on the lower Snake River primarily due to the severe negative impact these structures have on native fish populations. Built in the 1960s and 1970s to generate hydroelectric power and facilitate barge navigation to Lewiston, Idaho, these dams have been identified by environmentalists as a primary cause of the destruction and potential extinction of native spawning fish, particularly salmon.1

While these dams are equipped with fish-passage facilities, environmentalists argue that such technologies have proven difficult to sustain, leading to dramatic population declines for migrating fish. Consequently, the dams became the focus of significant removal initiatives in the 1990s, as advocates sought to restore the river's ecosystem and revitalize spawning populations.12