Seismic Shift – Part 2: Oregon Scientists Lead Effort to Prepare for Cascadia Earthquake and Tsunami
CORVALLIS, Ore. (KTVZ) — Oregon scientists are leading the world in tsunami research, helping communities better understand and prepare for one of the most destructive natural forces on Earth.
“It has been over 300 years since the last major earthquake rocked the region. And although there is no way to correctly time out the next one. The clock is ticking, and Oregon is in the line of fire,” said KTVZ Meteorologist Shannon Brady.
“And while most people have heard of the San Andreas Fault, the fault closest to Oregon may well be the epicenter for the next big one. It's called the Cascadia Subduction Zone,” said KTVZ Chief Meteorologist John Carroll.
Brady explained, “The Cascadia Subduction Zone is a fault line that lies roughly 100 miles off the Pacific Coast shoreline. Should a major earthquake along the fault line occur, coastal regions would be most impacted.”
Carroll added, “A little known byproduct of the shaking is called liquefaction. And it can cause catastrophic damage.”
“Liquefaction happens like this,” Brady said. “A major earthquake occurs on the ocean floor immediately due to the intense shaking along the loose, sandy shoreline, and how heavily saturated the ground is, the surface would lose its strength and sink. This could cause structures, trees, and anything else atop the shoreline to sink up to six feet.”
“And if that wasn't bad enough. Well, the tsunami off the coast has begun,” Carroll said. “Now, what occurs with that is we see offshore that a series of waves are building and pull the water away from the coast. That's called drawback. Now, the next phase of this is the inundation, where waves get larger and larger as they approach the coast. Energy is forced inland and the waves crash onshore.”
Brady continued, “A devastating tsunami could occur within 10 to 15 minutes after the initial shakes. And the coastlines will be overrun by a powerful wave of devastation.”
Carroll added, “But the first wave isn't always the last or the strongest. Multiple waves would likely hit the coast, and the largest of these could reach heights up to 100ft. The water coming onshore will surge inland. This graphic shows the inland push of water.”
“Fortunately, in Oregon, there are cliffs and mountains near the coastline that will slow down the eastern progression of the water. But the damage to the immediate coast would be incredible,” Brady said.
Carroll concluded, “The combination of the liquefaction process, weakening of any structural footings, and the surge of water inland, the damage from this big one will be catastrophic.”
“Large portions of the coast, including bridges, homes, power stations, sewage plants, and much more would be devastated for the days, weeks, and even months to follow,” Brady said.
Studying Tsunamis at Oregon State
At Oregon State University’s O.H. Hinsdale Wave Research Laboratory in Corvallis, tsunamis aren’t just a theory — they’re a force to understand. Using live model testing, researchers simulate how real tsunami waves might behave.
“We study different aspects of, tsunamis from, how the tsunamis are generated, how they propagate, and as well, how they interact with coastal structures,” said Pedro Lomonaco, director of the Oregon State Wave Research Lab. “If we know how the tsunami arrives, we can translate that into what are the fastest roads or more or safest routes for people or resources, to evacuate the, the coastline.”
It’s complex science with a simple goal: saving lives and livelihoods.
“When you have an improvement in the resilience of a community that impacts the economy and the life, the quality of life of the rest of the population, whether they are subject to that hazard or not,” Lomonaco said.
Turning science into action also means bridging the gap between research and real-world awareness.
“We try to do something that is called a community science, and it's basically, understanding how they understand risk, how, what are their ideas about tsunami risk,” said Erick Velasco, postdoctoral researcher at Oregon State University. “Our work is not only scientific or just, like, very technical, but also applicable to local communities. So we do these through, meetings with them. It's going to happen at some point, maybe tomorrow, maybe in 30 years, maybe in a hundred years, maybe in 400 years. We don't know and nobody knows yet. So the best thing that we can do is be prepared. It is important not to be scared. No, but to be prepared.”
What the Science Shows
Geologic data indicates these massive events typically occur between every 100 and 1,100 years. The last major earthquake along the Cascadia Subduction Zone struck in the year 1700 — more than 300 years ago.
“There’s actually been a tremendous amount of research, in the last five years on on Cascadia, both, looking to improve our understanding of, of the frequency of these events and how how big they are,” said Jonathan Allan, coastal geomorphologist with the Oregon Department of Geology and Mineral Industries.
“So during the actual earthquake itself, we can expect the coastline to subside over, over pretty much the entire length of the Oregon coast,” Allan said. “Then you had the tsunami itself that would eventually reach the coast and, begin inundating, you know, low lying areas, coastal communities, etc.. And of course, the tsunami itself would actually result in and, and catastrophic destruction of whatever it's in its way. You know, this entire landscape here would be completely stripped of, what we see here now.”
The devastation could isolate entire towns for months. With extensive landslides and Highway 101 expected to be cut off, preparing coastal residents is a high priority.
“Geology doesn't play here to any sort of a timetable, so. But this could be tomorrow. This could be in 50 years. But we do know it is coming. So we have to prepare. And we do prepare like it could happen tomorrow,” said Dan Norton, with Lincoln County Public Health’s emergency preparedness and response team. “Sometimes people can't wrap your head around it, and, they choose to just. Well, it's too big a thing to handle. We just won't do anything at all. Some preparation is always better than no preparation.”
Planning for the Future
Local and state agencies are working to ensure coastal communities are ready when disaster strikes.
“Yeah. Our agency really focuses on the long term land use planning side of things,” said Meg Reed, coastal policy specialist with the Oregon Department of Land Conservation and Development. “So it kind of thinking about how we can prepare our communities today for the event so that when it does arrive, they're more resilient. Afterwards they can recover and bounce back a lot faster. I believe it's the most studied, fault line in the world. So we have a lot more information now, but it's still it's getting that information from scientists into regulations, into communities every day lives.”
According to Oregon’s Resilience Plan, coastal residents could be without critical utilities for months or even years:
- Power: 3 to 6 months
- Drinking water and sewer: 1 to 3 years
- Evacuation roads: 6 to 12 months
- Health care facilities: up to 3 years
“They expect it'll take, years, probably to get things back up and operating. because of the challenging nature, it'll be basically like camping on the Oregon coast for a while,” Norton said.
Inland communities, including Central Oregon, are expected to become vital refuge zones for those displaced after a Cascadia event.
While the coast braces for impact, Central Oregon prepares for evacuees — because when the ground shifts, we’re all connected.
KTVZ News presents Seismic Shift, a special four-part series exploring how Central Oregon is connected to — and preparing for — the next major tsunami event along the Oregon Coast.
Part One: Lee Anderson sets the stage, explaining the science behind a potential tsunami and why experts say it’s a matter of when, not if.
Part Two: Claire Elmer takes us to the coast to show how communities and researchers are preparing for the inevitable.
Part Three: Spencer Sacks investigates what would happen next — how mass evacuation and infrastructure challenges would impact Central Oregon.
Part Four: Jillian Fortner highlights Deschutes County’s efforts to prepare as a safe haven, including new emergency operations and response planning.
