Experts say the Pacific Northwest has a 10-15% chance of a major earthquake in the next 50 years.
PORTLAND, Ore. — It started as a normal Thursday morning at Lincoln High School in Southwest Portland for senior Sarah Kane.
Then, just after 9:45 a.m., a voice came over the loudspeaker and her teacher instructed all the students to “duck, cover and hold on.”
Kane’s whole class, some of them giggling as they did it, scrambled under the desks and waited while the Great ShakeOut, a yearly earthquake drill, ran its course.
“It was definitely a little bit chaotic,” Kane said after the drill, noting that it was much more reassuring being in a new building. Lincoln HIgh School was just rebuilt with doors opening to students earlier this year.
“I remember in the last building, it felt like if I went under my desk it would have broken anyways even if there wasn’t an earthquake,” she said.
Thousands of Oregon residents and many more around the world registered to take part in the yearly exercise. The drill aims to remind people that while a major earthquake might not be at the top of everyone’s list of concerns, it’s something all of us should be prepared for.
Chris Goldfinger, a marine geologist and professor at Oregon State University, said the Cascadia Subduction Zone, the 600-mile long fault that runs from northern California to British Columbia, has produced 20 major earthquakes over the last 10,000 years.
“Those are the magnitude-9s, the so-called big ones, so that gives us a 10-15% chance in the next 50 years,” Goldfinger said.
An earthquake of that size could produce a devastating tsunami on the coast, Goldfinger said, but in Portland, the biggest concern is unreinforced masonry buildings, of which there are roughly 1,600 within city limits.
“Those structures are really quite fragile,” he said, adding that a Cascadia quake could produce strong shaking for three to five minutes. “They have no ability to withstand earthquake loadings at all.”
The students at Lincoln High should feel relatively at ease if that kind of quake strikes while they’re in school, according to David Mayne, communications manager for the Portland Public Schools’ bond program.
The school is brand new and was built to some exacting specifications.
“Lincoln is our newest high school. It’s our most modernized school,” Mayne said. “Part of the building is set at emergency level 4 which is like hospitals and police stations and fire stations. After a major event it’s a place where students can gather and safely occupy the building.”
Lincoln is one of 13 schools in the district that have either been fully retrofitted or completely rebuilt to withstand a major quake, Mayne said.
Many other schools have had incremental upgrades. The district, however, still has work to do.
“Most PPS schools were built before World War II, so they are very old. And they were built before a time when big seismic events were known about here,” Mayne said. “They’re beautiful old buildings but they aren’t modern to our times and the world we live in now. So it’s really important that we continue to upgrade these schools.”