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In B.C. it’s a given that all buildings
be engineered and designed to be earthquake-resistant. But
what about Alberta?
Many Albertans might think that ours is an earthquake-free
province. But, as Dr. Garry Rogers reminds us, this has not
always been the case.
Rare earthquakes do occur in Alberta, usually along the
ancient fault lines of the Rocky Mountains and foothills.
The last one, in 1984 in the Crowsnest Pass, measured 4.7
but did little damage.
“Alberta is just outside the edge of where most of
the damaging earthquakes occur,” says Dr. Rogers. “But
you still get the odd earthquake. And if they occur, they
can shake and damage large high-rise buildings many miles
away in cities like Calgary. So it’s necessary to put
earthquake-resistant design into those buildings.”
Dr. Rogers says most of today’s buildings are well
designed to withstand earthquakes.
“The buildings and structures that have gone up in
the last few decades are really state-of-the-art. And they’re
constantly getting better, as we learn more. The real vulnerability
in our cities right now isn’t the new buildings, but
the older structures, 50 years or more. And there are quite
of few of these throughout our cities.”
According to Dr. Rogers, advanced earthquake design can
also protect oil and gas pipelines and the like.
“Generally, oil and gas pipelines survive shaking
very well, unless they’re on a fault rupture or are
buried by a landslide. But even in these cases, industry
is taking steps to address this. In Alaska, the pipeline
that moves from the north slope down to Valdez has been designed
to allow the pipeline to move up to 15 metres in an earthquake,
using large Teflon sliders, so that it doesn’t break.
“And thanks goodness they did that. Otherwise, last
year’s earthquake in Alaska would have caused a major
oil spill.”
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