‘Massive’ B.C. landslide break expected in next 24 to 48 hours, officials say

Emergency officials said the massive landslide that is blocking the Chilcotin River, in B.C.’s central interior, prompting the evacuation of dozens of properties, is expected to cause flash flooding downstream when the river breaches the slide area.

Margo Wagner, chair of the Cariboo Regional District, said in an update on Thursday morning that the timeline of the breach is unknown but that a breach is expected.

“We don’t know exactly when this landslide is going to give way,” she said, “but we have heard it could be between the next 24 to 48 hours.”

Wagner added that the water will either rise above the top of the debris pile and flow over the top or it will cause a fissure to form through the debris field and eventually break through.

Rocks, mud and clay are blocking the major tributary to the Fraser River after a landslide came down overnight Tuesday about 60 kilometres from Williams Lake. Wagner said the slide occurred in a burned area from a 2017 wildfire that roared through the area.

An evacuation order is in place for 60 properties, including 13 homes.

A flood warning, flood watch and high streamflow advisory are also in effect.

“Water has been backing up behind the landslide,” Bowinn Ma, B.C.’s minister of emergency management and climate readiness, said.

“At this time it is only growing.”

Ma confirmed on Thursday that the province is coordinating with impacted communities and helicopters have been dispatched to help with technical assessments.

One person was hurt in the slide and was airlifted to the hospital with non-life-threatening injuries.

Evacuees were told to head north to Highway 20 and go to Williams Lake.

Loren Doerkson, MLA for the Cariboo-Chilcotin, said in an update posted to X that the debris slide is massive.