Historic Return of Chinook Salmon to Stuart Creek After PCI's Fish Passage Restoration
We're pleased to share significant news from Stuart Creek in the Sonoma Creek Watershed. In 2024, Chinook salmon have returned to their historic breeding grounds, marking a milestone achievement exactly 10 years after PCI Ecological's fish passage barrier removal project was completed.
Step Pool
A Decade in the Making
In 2014, PCI Ecological partnered with Sonoma Land Trust (SLT) to design and implement improvements for fish passage along Stuart Creek within SLT properties. The project addressed three critical human-made barriers that had long prevented steelhead and Chinook salmon from reaching essential spawning habitat:
Arnold Drive Culvert: We constructed a specialized low-flow channel or "fishway" to regulate water depths and velocities, with baffles installed to reduce water velocity during high flows while maintaining adequate depth during low flows.
Bridge Failure Site: At a location where channel downcutting had created a 5-foot drop, we designed a series of chutes with pools, creating a passable channel with rock-stabilized steps that ensure fish passage while preventing further erosion.
Glen Oaks Dam: This 10-foot-high historical structure presented the most significant challenge. Working within constraints to preserve the dam's historical significance, we widened a notch and lowered the spillway, reducing the drop to just over 1 foot while maintaining the high-quality perennial pool downstream.
Stuart Run Overview
Stuart Run Before
Stuart Run After
Success in Action
The recent sighting of Chinook salmon upstream of these removed barriers demonstrates the effectiveness of these restoration efforts. After a decade, these fish have found their way back to their ancestral spawning grounds, with expectations that steelhead will soon follow.
This project expanded the window of opportunity for salmonid spawners to reach previously inaccessible habitat. In total, we restored access to one mile of high-quality habitat upstream of Stuart Creek and 0.75 miles upstream of Glen Oaks Dam.
Glen Oaks Dam Before Restoration
Glen Oaks Dam After Restoration
Looking Ahead
Our work on Stuart Creek continues. One final fish passage barrier remains in the watershed, and PCI has already completed 100% design plans for its removal. We're currently working with Audubon Society and other partners to secure funding to implement this project in 2026. Once completed, this final barrier removal will restore access to an additional 0.5 miles of stream channel, opening the entire Stuart Creek watershed to migrating salmon.
The Power of Focused Restoration
This project exemplifies the significant gains possible when focusing on strategic sections of our streams. By removing key barriers, we can restore access to extensive high-quality habitat, making a substantial difference for threatened and endangered species.
At PCI, this kind of outcome validates our ecological restoration approach. We appreciate the opportunity to collaborate with excellent partners like Sonoma Land Trust and to observe such tangible results from our work.
The Sonoma Land Trust has produced a video showing Chinook salmon successfully passing the Glen Oaks Dam structure. This footage captures the fish utilizing the passage we designed, accessing the 0.75 miles of habitat that had been inaccessible for decades before our project.
Photo Descriptions:
SLT Video: Chinook swimming in the creek (video by Sonoma Land Trust)
Stuart Run Overview
Chinook Salmon in the creek (photo by Sonoma Land Trust)
Stuart Run before project implementation
Glen Oaks Dam after restoration