Fraser Canyon Slides & Impacts on Salmon
As so many saw in the fall of 2021, landslides can have serious impacts on BC's communities, infrastructure and transportation routes.
Slides can also have serious impacts on waterways — such as how and where rivers flow and how passable they become following a slide. One of the most serious of such recent slides was discovered in 2019 on the Fraser River near Clinton, known as the Big Bar Slide when salmon were obstructed from moving upstream, triggering a large response effort: see background. The project “Landslide impact on flow dynamics, fish migration and genetics of Fraser River salmon” examines how past and present slides in the Fraser River Canyon have affected river flows and migrating salmon populations.
A Fraser Landslides research site is now live on the SFU website. Stay current on the research underway on landslides, canyons of concern, hydraulics and flow dynamics, and salmon migration.
Late in 2018, a large amount of material broke away from the cliffs above the Fraser River, southwest of Clinton, BC, in a remote section of the river. The Big Bar Slide, as it was called, created a blockage in the river that significantly and negatively affected migrating salmon due to adverse water flows, and cost millions of dollars in ongoing mitigation costs. The slide was discovered in the summer of 2019, triggering response effort, including cliff stabilization and transfer of fish past the slide.
The impacts of another slide similar to the Big Bar Slide could be catastrophic. Migrating Fraser River salmon populations are at record low numbers, and another significant slide blocking migration could spell disaster for these already stressed and vulnerable salmon populations. However, the likelihood of a similar slide occurring again is unknown.
The project, “Landslide impact on flow dynamics, fish migration and genetics of Fraser River salmon” is a collaboration between academia and First Nations, and aims to understand how past and present slides in the Fraser River Canyon have affected river flows and subsequent migrating salmon populations. Analysis of past slide dynamics will be used to develop a predictive model of potential future slide activity, and may inform potential future slide response. Indigenous Knowledge holders will be engaged to assess the understanding of past slide events and their impacts on salmon migration in Fraser Canyon First Nations communities.
This three-year project will ultimately aim to assess the potential and risk of another slide blocking the Fraser River, and the impact of such a slide on migrating salmon.
Video Story - Bare Earth: Saving the Fraser River Salmon Migration
Thanks to the Hakai Institute team members who joined the Fraser Landslides Research team on the river in the summer of 2022. They are helping tell the story of saving the Fraser River salmon from the impacts of future landslides.
Jeremy Venditti [Principle Investigator], Elizabeth Dingle, Shawn Chartrand and Jon Moore - Simon Fraser University (SFU)
Brian Menounos - University of Northern British Columbia (UNBC)
Derek Heathfield - Hakai Institute (HI)
Greg Owens - University of Victoria (UVic)
Isaac Larsen - University of Massachusetts (UMass)
David Patterson, Kendra Robinson, Ben Sutherland, Mike Hawkshaw - Fisheries and Oceans Canada (DFO)
Kimberly Sivak - Project Manager, SFU
Erin Seagren - Research Manager, SFU
Facilitation, Engagement and Communications Team
Greg Witzky - Fraser Salmon Management Council
Kim Menounos and Lindsay Sackett - Fraser Basin Council
A look at the project research in action as Fraser River water loggers (pressure sensors) downstream of Hells Gate are used to measure water depth. These were installed along the Fraser to give the project research team a better idea of the water surface elevation and flow conditions at different river discharges (e.g., how does the water surface change across a rapid). The information will help determine how fish can potentially use flow conditions to migrate past problematic areas in the canyon, such as high velocity zones. Photo: Erin Seagren, Simon Fraser University
The project team is grateful for the contributions that make the project possible.
Kim Menounos, Northern Interior Regional Manager