The next time the Cascadia fault along the West Coast unleashes a magnitude-9 earthquake, the dams in east Skagit County could fail, dozens of bridges and overpasses could collapse on major roadways, and utilities could shut down.

The region's earthquake risks have been known for years, but gained additional attention following a July 2015 article in the New Yorker magazine that pointed out the devastation that could be caused by a severe quake.

"The article in the New Yorker last summer opened a lot of eyes. It was not bedtime reading," U.S. Rep. Derek Kilmer, D-Gig Harbor, said during a White House summit Feb. 2 on earthquake resilience. "The threat of an earthquake and a tsunami looms very largely in our lives."

Various levels of government, along with help from private investors and university researchers, are working on developing safeguards, including an earthquake early-warning system that could prevent damage and save lives.

The Cascadia fault is a subduction zone where one piece of the Earth's crust is sliding under another in the Pacific Ocean just off the West Coast. It stretches about 700 miles along from southern British Columbia to northern California. 

After decades of research, scientists concluded the last magnitude-9 earthquake along the Cascadia fault was in January 1700, and it sent a tsunami across the ocean to Japan.

It's impossible to say when the next Cascadia earthquake may come.

"We could be good for another 160 years or it could shake tomorrow," Skagit County Department of Emergency Management Director Mark Anderson said.

When it does strike, millions of people in Western Washington, Oregon and California will be at risk, said John Holdren, director of the White House Office of Science and Technology.

U.S. Secretary of the Interior Sally Jewell, who lives in Seattle, said during the summit that the region's last large earthquake — the Nisqually quake 15 years ago today — "rock and rolled our world." It had a magnitude of 6.8.  

The Nisqually quake damaged a historic smokestack along Anacortes' waterfront, shook bricks loose in downtown Mount Vernon's Pine Square and cracked walls at Madison Elementary School. 

The Nisqually earthquake caused about $654,000 in damages in Skagit County, according to county Emergency Management records. 

A magnitude-9 Cascadia earthquake could cost billions. 


Washington ranks second in the nation when it comes to being susceptible to severe earthquakes, according to FEMA. California, with the San Andreas fault, is No. 1.

A magnitude-9 earthquake along the Cascadia fault could cost Skagit County a handful of casualties, dozens of injuries, $114 million in building damage and $8 billion in total economic losses, according to the Washington State Seismic Hazards Catalog map.

The map, which is managed by the state Department of Natural Resources, shows that the oil refineries on March Point in Anacortes, several wastewater treatment systems in the county and the Northwest Pipeline that moves natural gas near Sedro-Woolley and Clear Lake could be damaged.

The floodplains of the Skagit and Samish rivers could liquefy, turning the land from solid ground to mush, according to the county Emergency Management's Natural Hazards Mitigation Plan.

Within two hours after the shaking stops, tsunami waves between 5 and 55 feet high could reach Skagit County's shorelines, according to the plan. That could put parts of Bow, Edison, Bay View, Fir Island, Samish Island and Anacortes underwater.

Existing infrastructure isn't expected to hold up, and Anderson said transportation is a particular concern.

County Emergency Management staff said a major Cascadia earthquake will damage the region's economy — perhaps 100 times worse than when the Interstate 5 bridge fell into the Skagit River on May 23, 2013.

It cost $19.8 million to replace the collapsed portion of the bridge. That cost doesn't include the impact on local businesses and interstate commerce.

The monthlong bridge closure impacted the more than 71,000 vehicles per day that use that route, according to the state Department of Transportation. 

"That was one bridge on one roadway. There are going to be multiple overpasses down on multiple roadways (following a major earthquake)," county Emergency Management Coordinator Dale Kloes said.

Kloes and Anderson said they also expect utilities, including communication, electricity, water, sewer and gas will be down, possibly for months.

"A major earthquake is going to take out all of it," Anderson said.

Early warning, combined with personal preparedness and infrastructure updates, could reduce the impact of a major earthquake.

“Washington state takes very seriously the risks that earthquakes and tsunamis pose to our people and communities. Being prepared makes all the difference between lives lost and lives saved,” Gov. Jay Inslee said in a prepared statement prior to the White House summit earlier this month.


For a surgeon performing an open-heart procedure, a school bus driver approaching a bridge, or a construction worker standing alongside heavy machinery, knowing an earthquake is coming can make a big difference. 

"Even a handful of seconds warning can mean the difference between life and death," Kilmer said. 

An early-warning system could detect the first waves of energy released by an earthquake and notify those in the danger zone. The warning could pop up on cellphones, computer screens and other devices.

"There's an app for that," Kilmer said.

At least there will be.

The U.S. Geological Survey, in partnership with other government and private organizations, has developed a program called ShakeAlert. It's the initial version of an app that could warn West Coast communities that a major earthquake is coming seconds or minutes before it strikes.

An early-warning system for the Cascadia region is expected to cost $38.3 million, according to project partners. Operating and maintaining the system is estimated to cost $16.1 million a year.

Experts say the expense would be worth it.

"It's going to give people enough notification to stop what they're doing ... If you've got 30 seconds to react, it could reduce the damage impact," Anderson said.

Tyler Dalton, disaster preparedness coordinator for Skagit Regional Health, said any advanced warning could help Skagit Valley Hospital staff, especially surgeons in the operating room. 

"If they realized the ground was going to start shaking they could stop whatever procedure they were working on to make sure they are safe and the patient is safe," he said. 

Even 30 seconds could be long enough to set down sharp objects such as scalpels, and secure large machinery such as portable X-ray machines, Dalton said.

The alert system could give those in the Pacific Northwest up to 5 minutes to take precautions, according to the Pacific Northwest Seismic Network.

Berkeley Seismology Lab Director Richard Allen said that's enough time to reduce earthquake injuries by up to 50 percent, which could save billions in medical costs.

Rebekah Paci-Green, director of the Resiliency Institute at Western Washington University, said an early-warning system could also be programmed to automatically shut down systems working with hazardous chemicals or important data, or stop trains in motion.

That could be key to preventing additional damage from derailments and explosions, she said.

Japan's early-warning system automatically stops trains and reduces the pressure of gas lines, said Paci-Green, who took a class on a visit to the country a year after it was struck by an earthquake and tsunami in March 2011.

Paci-Green and her students were impressed to see that the damage from the earthquake — which was about the same magnitude as the one that is expected along the Cascadia fault — was almost nonexistent. The majority of the damage Japan came from the tsunami that followed, she said.


While early warning has great potential for preventing damage during an earthquake, preparation is key to surviving the aftermath.

Individuals and families can take steps before, during and after an earthquake to protect themselves.

Residents should consider securing furniture that could fall during an earthquake, Kloes said. Doing that will prevent injuries and damage to the home.

Paci-Green said the biggest hazards during the actual shaking are shattered glass and falling objects such as books, furniture, soft ceilings, air ducts and lighting.

During the shaking, the basic rules are to drop, cover and hold.

If you're driving, stop and stay in the car. If you're at work or school, get under a desk. If you're outside, move away from buildings and get down on the ground.

After the shaking stops, there will be more hurdles ahead.

Kloes said he recommends households stock at least two weeks worth of supplies. Water, food, medications and supplies for babies and pets are among the most important things to have on hand during a disaster, he said.

"There's a misconception that the government will be right there at your doorstep, and in reality the services we use everyday just won't be available," Kloes said.

Anderson said with bridges down and electricity out, everything from fire and police response to grocery store services may be difficult, if not impossible, to access.

Phone systems likely will be overloaded, as they were following the Skagit River Bridge collapse in 2013.

Skagit County Community Emergency Response Team Coordinator Krista Salinas said after the bridge collapse callers got busy signals for hours because so many people were making calls at the same time. 

When that happens, text messaging is the best way to reach others, she said.


An early-warning system isn't worth much without infrastructure that can withstand what's ahead.

Paci-Green said while the risks posed by the Cascadia fault are gaining attention, more needs to be done to prepare.

"I'm hoping we won't get the earthquake before we have enough time to do so," she said.

Retrofits are needed to bring aging bridges, buildings and utilities up to current building codes.

Paci-Green estimates a Cascadia earthquake could damage thousands of buildings in the Puget Sound region, and leave dozens of bridges and freeway ramps unusable. Repairs could take years.

"Skagit County knows all about what happens when a bridge falls down ... getting supplies in and out gets problematic," she said.

Damaged utilities will further complicate recovery.

If water treatment plants aren't functioning, a boil advisory could be in place, but if electricity is down, many won't have access to working stoves.

"All of these things fit together. If the roads are damaged, crews can't get to repairs ... It starts to snowball pretty quickly," Paci-Green said.

Still, Skagit County will likely be better off than other areas.

Being fairly far inland from where the fault lies, most of Skagit County will experience moderate shaking, experts say. With islands blocking and breaking up waves before they arrive along Skagit County's shorelines, tsunami impacts shouldn't be too severe, either. 

Paci-Green said that means emergency responders and resources aren't likely to be focused here first. It also means that if prepared, north Puget Sound could help more severely-hit communities during the recovery process.

"It's going to be bad for us, but nothing compared to what our coastal communities are going to face," she said. 

— Reporter Kimberly Cauvel: 360-416-2199,, Twitter: @Kimberly_SVH,

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