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Hold onto your butts, people. Scientists have found that the shaking likely to be generated by a big-ass earthquake on the Cascadia subduction zone is worse than previously thought—and Seattle's current building codes aren't equipped to handle it.

The study, which was presented at the 2019 Seismological Society of America Annual Meeting last month, is based on the work of Nasser Marafi, a PhD candidate and structural engineer at UW. Marafi is part of UW's M9 Project (as in, “magnitude 9”), a team of researchers from physical sciences, mathematics, engineering, urban planning, and social sciences who are working together to try to figure out what the fuck is going to happen around here when the really big one hits. And the chances that it’s going to hit should have all of us in this region shaking in our fruit boots: Experts from the U.S. Geological Survey say there is a 14 percent chance that a magnitude 9 quake will hit in the next 50 years. That’s 14 times higher than Donald Trump’s chance of winning the 2016 Republican nomination.

Marafi told me in a phone interview that he used simulated 9.0 earthquakes by the USGS/UW to see how they would affect building structures located in “deep sedimentary basins” like the geological formations most Western Washington cities and towns are built on. During the last Ice Age, Marafi explained, layers of sediment were compacted between the Cascades and the Olympics. Now, that basin—basically all the land between the two mountain ranges—is home to lots and lots of people. And that’s a problem. “When seismic waves enter the basin, they amplify in intensity,” Marafi said. “And this effect isn’t considered in current building codes.”

As of December 2018, Seattle building codes were updated so that all buildings over 240 feet (or 24 stories) tall must consider the effects of deep sedimentary basins. But Marafi’s study found that it’s not just tall-ass buildings that could be affected. Turns out, reinforced concrete buildings shorter than 240 feet are also impacted by this phenomenon. The M9 Project has been working with the city to reform building codes, but the next round of updates are unlikely to be incorporated before 2022 or 2023. And some developers, of course, will do what they can to get out of them: Right before the last updates to the city building codes, a rash of building permits were filed.

“All developers are different and some want to build structures that will last for generations. And some want to maximize profit,” Marafi said. “But by [filing before code updates], they basically got a permit for a building that is at higher risk of damage.”

The city can and does update building codes as knowledge about seismic activity and other issues increases, but it can take a while for the slow wheels of bureaucracy to adjust. As for his study, “We knew going that things weren't going to look pretty,” Marafi says, but public awareness can help build momentum for government projects. In addition to putting pressure on developers and builders when investing in real estate, he advises concerned residents to call their elected officials out. “What do we need to do to make sure that once this quake happens, the Pacific Northwest can survive?” he wondered. That’s the question to ask.