Salmon return to the river after America’s largest dam demolition project

Biologists with the Oregon Department of Fish and Wildlife (ODFW) discovered Chinook salmon at the site of the former JC Boyle Dam on the upper Klamath River, Smithsonian reported on October 25. This is one of four dams that block salmon migration between the Klamath Basin and the Pacific Ocean. All four of these dams were recently demolished in the largest dam demolition project in American history, restoring the river to its natural, free-flowing state.

At first, biologists even wondered if they would actually see salmon. “We saw a large fish floating on the surface of the Klamath River the other day, but only the dorsal fin was visible,” said Mark Hereford, ODFW’s Klamath Fisheries Reintroduction project team leader.

Then, when they returned to the river, the team of experts was able to confirm that it was the fall migrating Chinook salmon. This made them the first to discover Chinook salmon in the region since 1912.

The return of salmon comes less than two months after dam removal projects in California and Oregon were completed. This is the result of a decades-long advocacy effort by conservation groups and many neighboring tribes – including the Yurok, Karuk, Shasta, Klamath, Hoopa Valley and several others – who are committed to with Chinook salmon.

Ron Reed, a member of the Karuk tribe and a traditional fisherman, joined the campaign in favor of removing the dam. He believes that restoring the river will help restore salmon and it is not surprising that after the project, they quickly returned to their ancestral waters. Reed and many others can now return to the fishing tradition.

The dams, built from the early 1900s to 1962, contributed to algae outbreaks and disease, blocking the annual salmon migration. By November 2022, the Federal Energy Regulatory Commission approved a $500 million dam demolition project. The first dam was destroyed in the fall of 2023. Starting in January of this year, the reservoirs of the remaining three dams were drained and the infrastructure demolished. At the end of August, for the first time in more than a century, the river flowed freely again.

Now that the dam system is gone, indigenous tribes are excited to see salmon return, able to swim in more than 640 km of river. Biologists believe the salmon discovered in Oregon likely swam about 370 kilometers from the Pacific Ocean to get there. However, most scientists believe it could take 3-5 generations for Chinook salmon to fully recover in this basin.