BUILT TO BREAK
Historic brick buildings in Bellingham could collapse in an earthquake.
Story by Rachel Hunter | Photos by Katy Cossette
Drop, cover and hold — this is still the standard practice during an earthquake. Possibly the most important part of this instruction is to cover. Cover yourself from things that might be falling: picture frames, bookshelves or maybe even the ceiling and walls around you.
In 2010, the Federal Emergency Management Agency assessed Bellingham, Washington for its earthquake building safety. Bellingham was ranked high risk, scoring a D on a scale from A to F. Many of the riskiest buildings surround shoppers who line the inside of historic shops and walk the cobblestone streets of the Fairhaven neighborhood.
A magnitude 9.0 earthquake, caused by a break of the Cascadia subduction zone where two tectonic plates meet off the Washington coast, would devastate parts of the Pacific Northwest, said Rebekah Paci-Green, director of the Resilience Institute at Western Washington University.
“‘The big one’ could happen next Tuesday, or it could happen in 500 years,” said Jackie Caplan-Auerbach, an associate professor of geology at Western Washington University. “Both would be in the realm of fairly normal.”
Unreinforced masonry buildings would be the most dangerous structures in Bellingham during an earthquake, Paci-Green said. These buildings, built with brick or stone, could crumble off their frames.
Whatcom County didn’t adopt seismic building codes until the mid-1970s, Paci-Green said. Builders didn’t fully understand earthquakes and structural design until the early 2000s. Many Bellingham buildings were built before these codes existed, and few have been retrofitted since their initial construction, she said.
“Earthquakes don’t kill people,” Caplan-Auerbach said. “Nobody dies from shaking to death. People die because buildings fall.”
Unless the building was built or retrofitted in the last 25 years, people living or working in any brick building in the small commercial center of Fairhaven, are at risk, said James Tinner, a building official in the Department of Planning and Development for the city of Bellingham. Nearly all of downtown and Fairhaven are lined with unreinforced masonry buildings.
Imagine a stack of rocks, one on top of the other, all stuck together by a sticky substance called mortar. There’s nothing but mortar to keep these rocks held together. In a big shake, like an earthquake, they will literally shake apart, Tinner said.
The old bank in the center of Fairhaven, now home to the boutique Three French Hens, was built in 1900. This building is a perfect example of an at-risk unreinforced masonry building, Tinner said. In a magnitude 9.0 earthquake, these buildings would collapse, he said.
Owners can retrofit a building, but it can be costly and must be planned far in advance, Caplan-Auerbach said.
Picture a shoe box with no lid. If you push in two opposing corners, it’s flimsy and will begin to cave in, Tinner said. Now put the lid on the shoe box and push in on the corners. The lid, connected to the rest of the box, reinforces it, and the sides no longer cave in. Connecting the roof and floors to the walls can help ensure a building’s survival and safety during an earthquake, he said.
In 2015, Western started renovating Carver Gymnasium. Seismic retrofitting is a major part of the renovation, Paci-Green said. Part of this process is connecting the floors, walls and ceiling together. On the east side of the building are two red diagonal steel beams for seismic support, Paci-Green said.
Unreinforced masonry is the most dangerous type of building, but it’s not necessarily the materials that pose risks; it’s how they’re put together, Paci-Green said. Brick, a very brittle material, is not the best to withstand an earthquake. But if it’s reinforced with steel or retrofitted, brick would hold up better.
In 2010, the National Hazards Earthquake Reduction Program published a formula to calculate the earthquake risk of every city in the United States. The assessment assigned each city a grade based on an equation looking at the safety of its buildings given the possible intensity of ground shaking, the city’s location and population. This assessment gave Bellingham a D grade.
Other states, like California, have stricter seismic codes for homes, offices and schools, Tinner said. If a picture or wall decoration is heavier than about two kilograms, it has to be bolted to the walls. If a hanging plant is connected to the ceiling, it has to be attached with two closed-eye hooks, according to a California schools earthquake guide. Washington does not have any of these strict codes, Tinner said.
The best thing people can do to prepare for an earthquake is to act as though it would happen tomorrow, Caplan-Auerbach said. It’s important for building owners to find out if their structures are seismically sound, she said.
Phyllis McKee does not worry much about ‘the big one.’ McKee owns both buildings in Finnegan’s Alley in Fairhaven. One was built in 2001, and the other was built over 90 years ago, she said. The newer building is up to date with seismic codes and the other was inspected and has no problems, McKee said.
Communities and individuals who assess their risks and make response plans are less likely to be impacted by casualties and damage, according to an earthquake risk assessment by FEMA.
“We need to recognize that this earthquake is going to happen, and that life will be better the better prepared we are,” Caplan-Auerbach said.