One year after four dams were removed on the Klamath River spanning the Oregon-California border, fall Chinook salmon have made it into previously inaccessible spawning grounds. Earlier this month, biologists confirmed that multiple Chinook have made it past the old dam sites and into tributaries of Upper Klamath Lake—the longest spawning migration recorded in the drainage for over a century, according to the local Yurok tribe. All said, about 440 miles of new spawning habitat were made available by the dam removals.
“The speed and scale of the river’s recovery has exceeded our expectations and even the most optimistic scientific modeling, proving that when the barriers fall, nature has an incredible power to heal itself,” said Barry McCovey Jr., director of the tribal fisheries department. Biologists were expecting it to take several years for sediment to clear out of the system, but the river has rebounded much faster than expected.
On September 24, the Oregon Department of Fish & Wildlife (ODFW) captured a video of a Chinook overtopping the Keno Dam fish ladder. The fish isn’t the first one to have made it over the dam (in fact, the camera was installed just one day before), but it’s exciting footage for those involved in the restoration. According to ODFW, several fish made it over Keno Dam last year too, just weeks after the demolition was complete. The entire run was around 700 fish, with most spawning in a section of river that was previously inundated by the backwaters of J.C Boyle Dam.
In this fall’s spawning migration, the king salmon have made it even further, passing the uppermost Link River Dam as well. The passage allows access into Upper Klamath Lake and several historical spawning tributaries, including the Williamson and Sprague rivers. In the preceding months, there was concern that toxic levels of cyanobacteria in the lake could have impacted the run (the state issued a “do not swim, do not drink” water advisory), but the fish appeared to have no problem. Several were detected in tributary streams to the reservoir within the last two weeks.
In addition to increased salmon returns, overall water quality in the lower Klamath River has improved substantially since the dam removals. Not only are summer and fall water temperatures colder, but the river has also seen lower algae concentrations. According to data collected by the Karuk Tribe, 58% of water samples collected prior to dam removal exceeded public health limits for toxic algae. Post removal, all water samples have tested below the limit.
Despite the success, restoration efforts could see less money in the coming years for continued monitoring. In late September, the Department of Interior revoked a $2.1 million grant to the Mid Klamath Watershed Council, part of which was dedicated to Chinook spawning surveys and habitat restoration. According to the department, the projects “no longer match its goals.”
Until now, however, there has been plenty of federal money available in the Klamath watershed. Oregon and California utility companies footed the $500 million bill for the dam removals, but the Department of Interior pledged $162 million toward restoration projects over a period of five years, thanks to the 2021 Bipartisan Infrastructure Law. The last of the money was awarded this year, with nearly $28 million being spent on everything from moving sediment to replanting floodplains to establishing stream gauges. Almost $2 million of that was spent implanting radio tags in Chinook salmon and establishing arrays throughout the basin to detect the tagged fish. The project is, in part, a major reason why such detailed data exists on how and where salmon are recolonizing the basin.
Going forward, it’s too early to tell how successful the spawning salmon will be. Juvenile Chinook spend one to two years rearing in freshwater streams before migrating to the ocean, so it will be several years until offspring from this year’s salmon run return to the Klamath.
The population will also be supplemented by heavy hatchery production. Last spring, the California Department of Fish and Wildlife released 400,000 fall Chinook fry into the river as well. The fish came from the brand new Fall Creek Fish Hatchery, which the state eventually hopes will produce 3.25 million fall-run chinook a year. PacifiCorp, the utility company that operated the Klamath dams, is set to fund the hatchery for eight years, after which biologists hope the fish will have established a self-sustaining population.
For the conservation community, the Klamath is a rare success story. Ultimately, the dams came down because it would have been more expensive for PacifiCorp to maintain them than to tear them apart, but it took prodding and collaboration from dozens of organizations to make it happen, and to subsequently restore the river to health. Watching salmon return to the drainage represents an important milestone and is a tangible result from years of groundwork.
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