For decades, four dams interrupted the Klamath River’s journey from southern Oregon through Northern California to the Pacific. In 2024, the last of those dams came down, reopening hundreds of miles of river to migrating fish. The change is historic—but it is better understood as the start of a restoration effort than its finish line.
The Klamath’s recovery depends on more than removing concrete. Fish need passable tributaries, suitable water conditions and functioning riverbanks. Newly exposed ground where reservoirs once stood must also develop into living landscapes. Those changes will take time, monitoring and work across a watershed that crosses state and tribal boundaries.
A river divided by dams
The Klamath flows from Oregon into California and reaches the Pacific near the town of Klamath. Its basin includes cold, high-elevation streams, larger rivers and wetlands, as well as drier landscapes. That range of habitats supports fish and other wildlife, while the river and its salmon are central to the histories and lifeways of Indigenous peoples in the region.
Four hydroelectric dams—J.C. Boyle, Copco 1, Copco 2 and Iron Gate—blocked fish from reaching much of the upper river and its tributaries. They were not the only pressures on the ecosystem: water management, degraded habitat and other challenges have also shaped the basin. But the dams formed a major barrier to fish migration.
After years of negotiation and planning, removal work began in 2023. The project was completed in 2024, making it the largest dam-removal project in U.S. history, according to the organizations involved. The removal reconnected reaches of river that had been separated for generations. It also meant that water, sediment and fish could move through places where reservoirs had stood.
Connectivity is an ecological change
For migratory fish, a connected river is not simply a longer route. It can provide access to spawning and rearing areas that were cut off by dams. Chinook salmon, coho salmon and steelhead are among the fish associated with the Klamath system. Lamprey and other aquatic species are part of the broader river community, too.
Reopening habitat does not guarantee that every fish population will rebound. Some fish may need time to find and use newly accessible streams. The condition of those streams matters: water temperature, flow, passage barriers and the availability of suitable spawning gravel can all affect whether a route becomes useful habitat. The river’s connection to the sea is one essential piece of recovery, not a substitute for care throughout the watershed.
The dam removals also changed the landscape of the former reservoirs. As water levels fell, exposed sediments and reservoir footprints required attention. Restoration plans include stabilizing and revegetating areas, with the aim of helping native plant communities take hold and limiting erosion. Those sites will change as vegetation establishes and as the river reshapes its channels and banks.
There is no instant switch from reservoir to mature river habitat. Ecological recovery unfolds through seasons and floods. Some places may green quickly; others may need repeated planting or other management. Monitoring can help show where restoration is taking hold and where additional work is needed.
Tribal leadership and a long view
The Klamath’s dam-removal story cannot be separated from the people who have depended on the river. Tribal nations, including the Yurok, Karuk and Klamath Tribes, have long pressed for a healthier river and the return of salmon to upstream waters. Their concerns involve fisheries, food, culture and the health of a living place—not only the engineering of a dam project.
That history also explains why restoration is larger than a single construction milestone. Removing barriers creates new possibilities, but it does not by itself resolve every issue affecting fish or communities. Work across the basin, including habitat restoration and attention to water conditions, remains important. Indigenous stewardship and knowledge are part of the continuing effort to understand what the river needs.
What comes next
The most meaningful test of the project will come over time: whether fish can reach and use newly accessible habitat, whether restored areas develop into functioning river landscapes, and whether the wider ecosystem becomes more resilient. Those outcomes require observation rather than assumption.
For now, the Klamath has regained something fundamental: a long, connected route through a landscape that dams once divided. The river will still face pressures, and restoration will take years. But a barrier that held back migration is gone, and the work has moved from dismantling dams to helping a river and its habitats recover.
