Is Vancouver Island Ready for a Large Quake?

September 26, 2017 - 11:00am

As an engineer who advises governments, organizations, and companies on how to prepare their buildings and facilities to survive earthquakes I have visited or sent teams to the aftermath of most key quakes in the world since 1970, observing how new and old buildings performed during the quakes and learning important lessons.

From my perspective, the Magnitude 8.8 quake that hit Chile on February 27, 2010 was the most important earthquake of the last 100 years – and particularly for British Colombia. It was the first mega-quake, its magnitude near 9, to strike a developed country with rigorous building codes. Modern cities full of state-of-the-art buildings were tested by intense ground shaking

that lasted more than 120 seconds — compared to about 40 seconds for the 1906 and 20 seconds for the 1989 San Francisco earthquakes, which had magnitudes of 7.9 and 6.9, respectively.

Unfortunately, despite Chile’s exacting construction codes, which for exceeded those of Vancouver and Western Canada, the performance of numerous new high-rise buildings was poor – two collapsed and many were not repairable. That was not expected.

As most of you know by now, the 600 mile long Cascadia Fault sits just off the west coast of British Columbia. Like the similar offshore fault that caused the quake and tsunami in Chile, Cascadia can produce temblors with magnitudes of 9 or greater, more powerful than anything we’ve experienced or expect from California’s famous San Andreas fault.

Cascadia’s last mega-quake, in January 1700, was approximately as large as Chile’s; it also caused a tsunami that pummeled Japan. Many seismologists and engineers believe the Pacific Northwest is overdue for another mega-quake. Yet in cities like Seattle, Vancouver and Portland, Ore., hardly any larger commercial or residential building is designed to withstand such a huge jolt. It is only a matter of time before a quake like the one in 1700 happens again in the Pacific Northwest — perhaps tomorrow, or not for 20, 50, 100 years. We do not know that precisely. But we do know that the earthquake will happen. And we also know that the consequences of not being ready can be catastrophic.

Is British Columbia ready? No, it is not. Is Vancouver Island ready? No, it is not - despite its even higher risk.

By Peter Yanev, the author of “Peace of Mind in Earthquake Country,” runs an international earthquake and structural engineering and risk consulting firm.

 

Peter will be presenting at the 11th annual Economic Summit in Nanaimo October 25/26 where he will share the top three things any business owner, institutional leader, or local government should do to manage their risk in case of natural disaster. His session is sponsored by the Vancouver Island Real Estate Board.