Big Bar Landslide remediation

In 2019, a significant landslide was discovered on the Fraser River that created an impassable barrier to several key salmon populations that spawn in the Upper Fraser watershed. The landslide occurred in a remote canyon near Big Bar Creek, British Columbia, on the traditional territory of several First Nations. More than 110,000 cubic metres of rock and debris sheared off a 125-metre high cliff and crashed into the river below. Without immediate intervention, these early migrating salmon stocks would be irreparably harmed.

An emergency response effort involving First Nations, the Province of BC, and the Government of Canada was initiated, with support from other agencies, stakeholder groups, and geotechnical and hydrological experts. Through this tripartite governance significant resources were mobilized to lessen the impact of the landslide on migrating salmon. The emergency response included rock scaling to stabilize the cliffs above, extensive blasting and removal of slide material, and intensive enhancement and biological monitoring work. A notable achievement was the creation of a permanent “nature-like” fishway that helps salmon migrate upriver by reducing the speed of water on the west side of the canyon.

The tripartite governance is an integral component of the ongoing planning and decision-making process at Big Bar. It continued to lead the effort to remediate the effects of the landslide and execute operational field work for enhancement and fish tracking in 2022. The Joint Executive Steering Committee and the First Nations Leadership Panel are examples of the committees engaged in the response.

Since the completion of the large engineering works at site, early migrating salmon are successfully navigating through the canyon and using the “nature-like” fishway. In 2022, salmon passage through Big Bar occurred without significant delay and an estimated 2.9 million Pacific salmon passed through the slide site.

In 2022, the enhancement program collected some 400,000 Chinook eggs and 618,500 sockeye eggs to rear into fry and smolts before their eventual release back into the Upper Fraser watershed. An additional release of 180,000 sockeye into both the Takla and Stuart Lakes at Fort St. James will support rebuilding the highly affected Early Stuart population that was decimated in 2019 and 2020.

Fiscal year 2022-23 marked the fourth season of Pacific salmon recovery efforts at the site. The trilateral governance structure is reviewing next steps at the conclusion of a recent strategic decision-making process. The plan includes the continued monitoring of passage conditions, the tracking and monitoring of spawning salmon, and the ongoing enhancement of at-risk populations.

Videos

• Salmon fry releases with First Nations
• Big Bar landslide response: 2021 roadwork operations
• Trilateral partnership: The Big Bar landslide response in British Columbia
• An ever-changing landscape: The Big Bar landslide response in British Columbia
• 2020 Fish wheel operations at the Big Bar landslide response in British Columbia
• The science behind monitoring at the Big Bar landslide response in British Columbia
• Alternative fish passage systems at the Big Bar landslide response in British Columbia
• Emergency salmon conservation enhancement at the Big Bar landslide response in British Columbia