Nearly a dozen chinook salmon have swum the 12 miles upstream from the San Francisco Bay through Alameda Creek into Niles Canyon—likely the first salmon to spawn there in 30 years, according to Jeff Miller, founder of the Alameda Creek Alliance. 

From its mouth in the East Bay, between the San Mateo and Dumbarton bridges, Alameda Creek leads forty miles east into the Sunol Wilderness through abundant potential spawning grounds. But dams, pipelines, bridges, and other human structures in the creek blocked fish from that potential paradise in 1967. Since 1998, the Alameda Creek Alliance, a grassroots advocacy group, has worked alongside agencies, nonprofits, and community members to take down these barriers one by one. Two multimillion-dollar fish ladders opened the route to Niles Canyon in 2022. This September, the mainstem creek’s last remaining barrier, a concrete mat over a PG&E gas pipeline, was removed. Bay Nature featured the watershed moment—and the decades of advocacy that led up to it—in a May 2025 story, “After 28 Years, Alameda Creek Opens Up to Fish.” 

On Wednesday, Claire Buchanan, CalTrout’s central California regional director, spotted one chinook that went even farther—it was crossing the former pipeline, some 20 miles upstream from the mouth. 

A chinook salmon crosses a former fish barrier. (Claire Buchanan, CalTrout)

These chinooks are likely hatchery strays, says Miller. But they are still an ecosystem boon, bringing nutrients into the stream. They also serve as flaming-bright symbols of restoration-at-work to the public—proof that salmon can find their way to new spawning grounds. Chinook salmon males redden as they prepare to spawn and develop a characteristic hooked jaw. Volunteers spotted both males and (hopefully egg-laden) females crossing the former barriers on the lower creek last week.

Volunteers with the Alameda Creek Alliance as well as agency staff are watching the creek for salmon and trout—and now looking for where they might have spawned. (Left, David Young; right, Dan Sarka)

As the fish now swim up through Niles Canyon, the females will search for quiet spots to lay their eggs, which males will then fertilize. This part, Miller doesn’t worry about helping along. “They’re pretty good at what they do,” he says.