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Pemberton, SLRD prepare for Great BC Shakeout

BC gets ready for the largest earthquake drill in its history



Drop... and cover.

It's a tactic familiar to children of the Cold War and it's being used again as the province prepares for the 2011 Great British Columbia ShakeOut, to take place January 26 at 10 a.m. in 101 communities.

The event is basically a province-wide earthquake drill with participation voluntary. A website states that 290,000 people are participating including 431 schools, 138 provincial government institutions and 69 federal government ministries and Crown corporations.

The Squamish-Lillooet Regional District, alongside the Village of Pemberton and the District of Squamish, is one of three Sea to Sky governments taking part in the drill. The SLRD administers unincorporated areas throughout the Sea to Sky region including Furry Creek, Britannia Beach and Birken.

"We have areas at risk for earthquakes," said SLRD administrator Paul Edgington. "An earthquake could occur anywhere based on the Juan de Fuca fault and other things. "Greater areas at risk are in Howe Sound. The other thing would be earth movements that would impact some of the mountains such as Mount Meager (and) the Barrier. They're higher order of magnitude risks."

British Columbia has been raring for a big quake since January 26, 1700. Back then an 8.7 to 9.2 megathrust earthquake rocked the province, causing a tsunami that reached as far as Japan. A megathrust earthquake occurs at subduction zones, when one tectonic plate is forced under another.

Dr. John Cassidy, a geoscientist with the Pacific Geoscience Centre on Vancouver Island, said that such earthquakes happen once every 250 to 850 years, which means coastal British Columbia has been overdue for its next quake since about 1950.

The Great ShakeOut is actually timed to the anniversary of the great quake that hit B.C. so long ago.

"We have a relatively short history," said Cassidy. "Sometimes it's 250 years between those earthquakes and other times it's about 850 years, so we can't predict them and we can't say when that might occur, but we're certainly into the time window when we could expect that type of an earthquake.

"Certainly, these giant offshore earthquakes are similar to the ones in Sumatra and Chile recently."

Cassidy estimates the earthquake would happen somewhere offshore, perhaps just west of Vancouver Island. It would extend from northern Vancouver Island along a 1,000 kilometre-long fault to northern California and they can happen anywhere along the fault.

In 2001 Seattle, Washington experienced a 6.8 earthquake that collapsed sections of a highway. Sometimes earthquakes help relieve tension along a fault that can build for centuries, but Cassidy said there's no way to know how much tension was relieved in that shakeup.

One of the biggest earthquake risks for Sea to Sky residents is a landslide, living as most of them do in the shadows of mountains. A landslide with enough debris flow, falling fast enough could cause a tsunami in Howe Sound.

Further north in Pemberton, an earthquake with enough strength could shake more debris off Mount Meager, which bore witness to the second biggest landslide in Canadian history last summer. Edgington said there's more that could come off the mountain yet.

"It would really depend on, I think, the time of year it occurred and the extent of material that might come down," he said.

"If an earthquake occurred in relatively dry weather, the impoundment and the threat of dam breach, temporary dam breach that we had last year, I guess during the freshet it could be significant."

Village of Pemberton Mayor Jordan Sturdy, meanwhile, said the local government is participating in the drill in order to create awareness of different kinds of hazards that can arise due to earthquakes.

"We want an opportunity to think about it and prepare for it," he said. "I think it's necessary for everybody. We live in a very geologically active area, I think to believe that nothing will ever happen is a bit naïve."

To find out more about the drill go to