UPDATE: Northwest Still Unprepared for Catastrophic Earthquake and Tsunami

On July 20, 2015, The New Yorker magazine ran an article flatly proclaiming that an earthquake caused by an undersea fault lying beneath the coastal areas of Northern California, Oregon and Washington will destroy a sizeable portion of the coastal Northwest.  The only question is “when?”

Cascadia’s Subduction Zone is an undersea fault that divides the Juan de Fuca oceanic tectonic plate from the North America continental plate. It runs from British Columbia down to northern California. It is part of the Pacific “ring of fire,” an area of high seismic and volcanic activity stretching from New Zealand in the South Pacific up through Japan, across to Alaska and down the west coasts of North and South America. So the earthquake prediction isn’t fear-mongering, or hype. It is based on scientific consensus. That’s why it is so frightening.

Other media quickly picked up on the warning, citing projections by the Federal Emergency Management Agency (FEMA) that nearly thirteen thousand people will die in the Cascadia earthquake and resulting tsunami, with twenty-seven thousand injured, up to a million displaced and homeless, and another two and a half million in need of food and water. Kenneth Murphy, who directs FEMA’s Region X, the division responsible for Oregon, Washington, Idaho, and Alaska, was quoted as saying “Our operating assumption is that everything west of Interstate 5 will be toast.”

The terrified public was reassured a week later when the magazine ran a follow-up piece by reporter Kathryn Schulz titled “How to Stay Safe When the Big One Comes” which offered advice on preparing for one of the worst natural disasters in recorded history.  Ms. Schulz explained that the “toast” comment wasn’t as hopeless as it seemed. What Mr. Murphy meant, she said, was that FEMA expected “to see seriously damaged or destroyed eighty-eight per cent of ports and potable water sources; seventy-seven per cent of fire stations and waste-water treatment plants; two-thirds of all airports, hospitals, railways, and schools; almost half of all highway bridges, police stations, and emergency command centers; plus almost three thousand miles of natural gas pipelines, seven hundred and forty-three electric power facilities, and nearly a million residential buildings.”

Oh, that’s all.  

To her credit, Ms. Schulz followed this litany of destruction with an honest assessment: “That does start to seem pretty toast-like.”

The article continued by advising anyone living west of the Cascade Mountains to bolt their house to its foundation, strap down their water heater and get to know their neighbors, since they would be the de facto first responders. People living in the tsunami inundation zone were advised to make an emergency evacuation plan.

After a flurry of interest, the public’s attention turned to other things. But experts know that authorities are still woefully unprepared to respond to an earthquake and tsunami of this magnitude.

Well before the recent publicity, scientists were aware of the danger.

On June 10, 2014, Douglas Toomey, a professor of geophysics at the University of Oregon leading the Cascadia Initiative, a $30 million project funded by the National Science Foundation that features the largest array of onshore‐offshore earthquake‐measuring instruments in U.S. history, testified before the U.S. House of Representatives at an oversight hearing titled “Whole Lotta Shakin’: An Examination of America’s Earthquake Early Warning System Development and Implementation”.  Dr. Toomey was blunt:

“A magnitude 9 (M9) earthquake and tsunami comparable to those that occurred in Alaska in 1964, Sumatra in 2004, Chile in 2010, and Japan in 2011, has, and will again, hit the Pacific Northwest. The source of this devastating earthquake will be the Cascadia Subduction Zone, which lies beneath the coastal areas of Northern California, Oregon and Washington. It’s been more than 300 years since the last great earthquake and tsunami along the subduction zone, and we’re in the window for its recurrence; we know that enough energy has built up as deformation in the rocks around the fault to power a magnitude 9 quake.

“The Pacific Northwest is unprepared for a catastrophe of this scale. FEMA estimates that the direct financial losses would be $60 billion, while the Insurance Bureau of Canada expects losses of approximately $75 billion in Canada. By comparison, the estimated losses from the Christchurch, New Zealand, magnitude 6 earthquake exceeds $18 billion, and in a January 2012 press release, the reinsurer Munich RE estimated Japanese losses at $210 billion.”

Dr. Toomey also testified that an Earthquake Early Warning system could provide Portland with as much as three minutes warning, and Seattle as much as five minutes, prior to the earthquake hitting.

But the earthquake won’t be the worst of it. Waves from the tsunami generated when the Cascadia fault slips will hit within 15 to 30 minutes, leaving little time for evacuation in the inundation zones.  Imagine a seven-hundred-mile wall of seawater up to 100 feet high crashing up to three miles inland. The area of impact will cover approximately one hundred forty thousand square miles and affect up to seven million people. 

According to University of Washington tsunami expert Jody Bourgeois, despite the death toll from the 2011 Japanese tsunami, 90 percent of the people in the inundation zones made it to safety because they knew what to do and had practiced evacuations.  Japan also provides tsunami alerts to the public via cellphone. But because such tsunami awareness and training in the Northwest are far less than in Japan, she predicted that the American survival rate wouldn’t be nearly that high.

Dr. Toomey’s team has been coordinating with a joint Japanese-Canadian team, monitoring seismic activity at listening posts from Vancouver Island to Northern California. The seismometers measuring activity in the fault zone between 40 and 80 miles offshore have detected little activity.

“What is extraordinary is that all of Cascadia is quiet. It’s extraordinarily quiet when you compare it to other subduction zones globally,” Toomey said.

In other words, it’s too quiet. This has led researchers to conclude that the fault zone is fully “locked” and that the colliding tectonic plates are completely stuck.

“If there were low levels of offshore seismicity, then we could say some strain is being released by the smaller events,” Toomey said. “If it is completely locked, it means it is increasingly storing energy and that has to be released at some point.”

Scientists are left wondering how much strain has accumulated since the plate boundary seized up and how much more pressure can build up before the fault rips and unleashes a magnitude-9