Four dams built on the Klamath River between 1918 and 1966 made power, not water storage; in 2024, the last came down, reopening 420 miles of salmon habitat

At times, the best way to move forward can be by taking something down. Four hydroelectric dams operated in California and Oregon’s Klamath River, the oldest of them for more than a century, altering the water body that had long been home to salmon and native populations, as well as a significant part of their livelihood and culture. And in 2024, the last of the four dams was removed. According to a NOAA Fisheries press release, the removal of these dams opened up roughly 420 miles of salmon habitat.

However, the project on the Klamath River wasn't only about demolishing four dams and allowing the water to flow freely. The effort that went behind it was a product of decades of negotiations between tribes, local communities, governmental agencies, conservation organizations, and even the utility company that owned the dams. It stands as the biggest dam removal project in history.

Four dams and barely any reason to keep them standing


The four dams on the lower Klamath, namely Copco No. 1, Copco No. 2, J.C. Boyle, and Iron Gate, constructed between 1918 and 1962, had never held water for drinking, irrigation, or flood control. These dams served only one purpose: production of hydroelectric power. By the 2010s, they did even that poorly; together, they generated less than 2 percent of PacifiCorp's total energy output. When the federal government ordered upgrades so that the dams would comply with the new standards regarding fish passage and water quality, the utility calculated the cost and found that it would be cheaper to demolish them.

A century of damage, and a 2002 disaster that lit the fuse

The Klamath River was once the third-largest producer of salmon on the West Coast of North America. The dams blocked all that productivity, and salmon populations declined drastically to levels of only a fraction of their previous numbers by the early 2000s. Finally, the last straw occurred in 2002, when the lack of water flow from Iron Gate Dam led to the death of about 30,000 to 70,000 adult salmon. This incident compelled the Yurok and associated tribes, such as the Karuk and Klamath Tribes, to launch a twenty-year battle for removal of the dams. Removal finally commenced in 2023 and was completed on October 2, 2024, ahead of schedule.

Why scientists are cautiously optimistic

This is not the first attempt by the US to do this. In 2014, two dams in the Elwha River in the state of Washington were removed to allow access to more than 70 miles of new habitat. According to a 2021 peer-reviewed study titled “Reconnecting the Elwha River: Spatial Patterns of Fish Response to Dam Removal,” published in the journal Frontiers in Ecology and Evolution, eight species of migratory fish, including Chinook and steelhead, had colonized the area upstream of where the dams previously stood in just two and a half years; some density of Chinook even surpassed the highest levels ever recorded downstream before removal.

This is the best precedent the Klamath project has to offer, which seems quite promising. However, the 2021 study makes one thing clear: recovery took years, not months, and that some species, such as pink and chum salmon, are still struggling to survive on the Elwha even more than ten years after the demolition of the dams. NOAA scientists expect an equally long timeline for the Klamath, aiming to restore approximately four to five self-sufficient salmon generations, or takes about 12 to 25 years. Under favorable conditions, their models project that Chinook salmon returns could climb by up to 80 percent over the next 30 years.

The work isn't finished when the concrete is gone

Rather than declare victory and move on, the federal agency invested around $20 million into post-removal restoration efforts: $18 million into floodplain and cold-water tributary restoration for the Yurok Tribe, and almost $2 million to allow wildlife officials from Oregon to study fish passage at the Keno Dam, an obstacle further upstream that blocks access to another 350 miles of river beyond the 420 miles already reopened by the removal of the lower four dams.

In this regard, the Klamath River project is perhaps an example of how a country that dammed many of its rivers in the 20th century in the name of progress and development is now required to undertake projects that serve as a tacit acknowledgement that some forms of progress may need to be undone in the future. It is not just a solution, but rather an extremely costly and extremely belated apology to both the salmon and the native populations.