B.C. report warns magnitude 9.0 earthquake could kill thousands, cause $128B in damage

A massive earthquake off the coast of Vancouver Island could result in thousands of deaths and widespread destruction across British Columbia, according to a new provincial risk assessment.

The B.C. government report estimates that a magnitude 9.0 megathrust earthquake could cause more than 3,400 fatalities and leave over 10,000 people injured. Economic losses are projected at $128 billion, with roughly 18,000 buildings destroyed and extensive damage to another 10,000.

The findings are part of the province’s disaster and climate risk assessment, which identifies a large offshore earthquake as one of the more likely seismic threats facing B.C. The report highlights Vancouver Island and a 20-kilometre stretch of the mainland, including Vancouver and communities from the U.S. border to the Sunshine Coast, as areas facing the heaviest impacts.

The scenario also outlines the risk of a tsunami, with waves expected to reach the west coast of Vancouver Island within 10 to 20 minutes of the quake. Coastal areas on the east side of the island and parts of the Lower Mainland could see tsunami impacts between 30 and 60 minutes later.

Beyond shaking and flooding, the report warns that a major earthquake would likely trigger strong aftershocks, landslides, soil liquefaction, fires and flooding, further complicating emergency response and recovery efforts.

According to the assessment, the last earthquake of similar scale in the region occurred in 1700. The province estimates the likelihood of such an extreme event happening in the next 30 years at between two and 10 per cent, underscoring the importance of preparedness and resilience planning for communities across B.C.