What to do when Cascadia hits

It’s not that simple, according to Chris Goldfinger, a professor of marine geology at Oregon State University, who is considered one of the world’s foremost experts on earthquakes.
Goldfinger was interviewed for the PBS Terra program “Weathered,” hosted by weather expert Maiya May, which, according to the show’s synopsis, “helps explain the most common natural disasters, what causes them, how they’re changing, and what we can do to prepare.”
“What you do the instant an earthquake hits matters a lot,” said May in her opening monologue. “The right decision could save your life, but if you watch the first 100 videos on YouTube that capture the exact moment an earthquake hits, almost no one does the three things that authorities tell us to do: drop, cover and hold on.”
On a previous episode of “Weathered,” Goldfinger asserted that the Cascadia Subduction Zone megaquake, anticipated by scientists to hit the Pacific Northwest in the next few decades, will be the “worst disaster in modern history.”
During the Oct. 18 episode of “Weathered,” Goldfinger returned to relay his findings on what the best course of action is in the face of a quake, and what scenarios the “duck, cover and hold” method does not cover. He said “there wasn’t scientific literature underlying” duck, cover and hold. “That’s kind of what got me started wondering how well that would work out in a real situation.”
Goldfinger’s research yielded that American society first embraced duck, cover and hold during the Cold War, when paranoia was widespread that nuclear war would break out between the U.S. and Soviet Union. The OSU scientist traced the first use of the phrase “duck and cover” to a 1952 Civil Defense cartoon depicting Bert the Turtle. “When danger threatened him he never got hurt; he knew just what to do,” a jingle in the toon harmonized. “He’d duck – and cover.”
“We were trained as kids to get under our desks in case of nuclear attack during the Cold War, and along the way that ‘get under your desk’ concept was just transferred from nuclear attack to just multi-hazard,” Goldfinger said. “So now it’s taught universally as the protective action for earthquakes.”
Whether or not duck, cover and hold is the right strategy for one to employ in the event they find themself in the midst of an earthquake depends on two crucial factors, according to experts: what type of earthquake and what type of building they’re in.
Surface level earthquakes start shaking the ground at full power almost instantaneously, so victims will have no time to decide whether to stay put or evacuate their current position.
However, subduction zone earthquakes, which take place at fault lines separating the earth’s tectonic plates, “actually give us a warning because the vibrations they cause travel at different speeds,” said May.
P-Waves travel faster than the other waves produced by earthquakes, and they cause a lighter shaking, meaning that Oregonians will feel a light shaking briefly before the more devastating waves of Cascadia wreak havoc upon their communities. So if they are in a weaker building that’s more likely to collapse, they can use this warning to evacuate.
May stressed, “That’s crucial time you don’t want to waste because all the bridges in places like Portland and Seattle will collapse. Whole neighborhoods and industrial buildings that were built on liquefiable soil will slough into waterways. Landslides, oil spills, explosions – it’s really an apocalyptic scenario.”
The fact that the impending Cascadia will be a subduction zone quake means you will be posed with the question of whether to stay put or get up and go by those initial P-Waves. So what determines the answer?
“What type of building you’re in when the big one hits plays a big role in whether or not you survive,” said May.
According to the “Weathered” host, 70% of the West Coast’s infrastructure is not up to modern standards if you exclude wood frame houses. OSU professor of structural engineering Erica Fischer says she would be concerned that any building constructed before the mid-90s is at risk of collapsing, as the Cascadia subduction zone was not discovered until 1988, and therefore seismic resilience was not factored in by architects until that time.
“The deciding factor for whether to evacuate or duck, cover and hold is situational awareness,” said Fischer. She added that knowing where you are going is just as important as knowing where you are when Cascadia hits. For example, if you are in a vulnerable building, but running outside means being below other vulnerable buildings that may collapse on you, it probably isn’t any safer to go outside than stay put where you are.
The documentary concludes that single family homes are among the safest places you can find yourself when Cascadia strikes, which is why a nighttime earthquake is said to be the best case scenario: Most people will be at home in bed.
“They are very flexible,” Fischer said of stick-built single family homes. “And so there are very specific details that we’re concerned about as it pertains to life safety. We’re concerned about chimneys, our bookshelves, overhead light fixtures that could fall and we’re concerned about porches.”
May added, “Because falling objects are the major concern in homes, ducking and covering might be the safest thing to do.”
Some dangerous spots many will inevitably find themselves in during Cascadia are non-ductile concrete buildings and unreinforced masonry buildings.
On the former, Fischer commented, “(Concrete) is very brittle. It’s like glass. It will fail suddenly. You’d see crushing of the concrete at the base of our columns. We would see damage at the joints between our beams and our columns.”
May concluded, “All that could add up to the building collapsing.”
Fischer remarked, “The most dangerous buildings that we’re concerned about are the unreinforced masonry buildings. All of the timber framing for the floors are pocketed into the masonry wall. So there’s no mechanical connection; as the building shakes back and forth, the two will separate. The wall will fall, usually outwards onto the street. There’s nothing holding up the floors themselves and those will collapse.”
Unfortunately, there are a great many unreinforced masonry buildings in larger cities. But on a positive note, most buildings erected since the mid-90s will “perform really well in an earthquake,” according to Fischer, and many buildings built before then have been or will be retrofitted to withstand seismic activity.
So the short answer to what you should do in an earthquake: Drop, cover and hold if you are in a house or newer building; get yourself outside if you are in an older building.
If scientists’ predictions come to fruition, the Cascadia subduction zone megaquake will be the worst natural disaster in modern history. For context, the death toll of the 2011 Tohoku, Japan earthquake was 19,747 and the 2004 Indonesia earthquake killed 227,898. Both were Category 9 subduction zone quakes, the same as Cascadia is anticipated to be.
Using situational awareness, you can avoid becoming part of Cascadia’s statistics when it hits.
“Humans are pretty smart,” said Goldfinger. “We are capable of learning complicated things, and learning what to do in an earthquake is far easier than learning how to drive a car. You have to learn to drive a car properly or you may not survive. And I think people have to learn how to deal with earthquakes, or we may not survive either.”