Tag Archives: Seismology

Earthquake: What will it take to get ready, and why should I prepare?

Store plenty of water. That’s my first bit of advice for earthquake preparedness. I suggest storing water for drinking — enough to last a week — and maybe some extra water for washing and cleaning.

If we’re going to prepare for an earthquake, let’s prepare for a big one. Then we’ll be ready for smaller ones or even severe storms with the potential to isolate us. Getting ready for an emergency can help reduce the anxiety of thinking about a long power outage, broken water pipes and other damage. Do what you can, then realize that recovery will come, though it could take time.

The 6.8-magnitude Nisqually quake, centered near Olympia in 2001, caused extensive damage to Highway 302 on the Kitsap Peninsula. But that quake could be considered small compared to what might result from a quake on the shallow Seattle fault. Kitsap Sun file photo
The 6.8-magnitude Nisqually quake, centered near Olympia in 2001, caused extensive damage to Highway 302 on the Kitsap Peninsula. But that quake could be considered small compared to what might result from a quake on the shallow Seattle fault.
Kitsap Sun file photo

If you would rather ignore the dangers, I guess that’s one option for dealing with this kind of anxiety. But it could be a costly approach, one ultimately filled with regret.

I recently had the privilege to be part of a team of reporters who wrote about the effects of a 7.2-magnitude earthquake along the Seattle fault. If you haven’t read the stories in the Kitsap Sun, I urge you to take a look at “The Danger Below Us.”

It may seem like a random number — 7.2 magnitude, large for any earthquake — but people need to understand that this earthquake would occur at or near ground level on a fault that runs through the center of Kitsap and King counties. That’s essentially right next door to hundreds of thousands of people.

Such an earthquake is not imaginary. It has happened before — long before any cities were built. Where the fault broke free, the land and seabed were raised upwards by more than 20 feet. Evidence is still visible at the south end of Bainbridge Island, where a submerged beach is now high and dry.

Restoration Point on Bainbridge Island was lifted more than 20 feet by an earthquake on the Seattle fault. Photo: Washington Department of Ecology
Restoration Point on Bainbridge Island was uplifted 20 feet by an earthquake on the Seattle fault.
Photo: Washington Department of Ecology

Most of us have heard concerns about the worrisome Cascadia subduction zone earthquake, which raised alarms after the New Yorker magazine described its potential effects. But for many residents of Puget Sound, a quake on the Seattle fault could be far worse, though probably less likely over the next 50 years.

The Kitsap Sun stories were based upon an earthquake scenario developed by the Federal Emergency Management Agency and presented to local governments in a “Draft Risk Report.” A separate scenario for a 6.7-magnitude quake was developed in 2005 by Earthquake Engineering Research Institute, which modeled the effects of fault rupture from Seattle through Bellevue to the east.

Shake map for Kitsap County (click to enlarge)
Shake map for Kitsap County (click to enlarge)

The death and destruction in either scenario is hard to imagine, and who wants to think about devastation in this seemingly peaceful part of the world? Keep in mind that even in a worst case, most people will survive to rebuild and go on with their lives, as they have in other parts of the world, including Japan. As we have learned from other areas, being prepared can make a real difference.

When I think about getting prepared, I begin with water. We cannot live without it. The preparedness list published on the Kitsap Sun’s website includes developing an emergency plan for your family, addressing structural problems with your house, learning first aid and several other things.

I was thrilled to hear about the attitudes of people in a Port Orchard neighborhood where families worked together to develop a neighborhood emergency plan. I learned a lot in the story by reporter Tristan Baurick. If you would like to help organize your neighborhood, Kitsap County Department of Emergency Management (PDF 373 kb) can help.

Reporter Ed Friedrich wrote about the potential damage to Navy facilities, and reporter Tad Sooter wrote about how businesses are coping with the risks of an earthquake.

Seattle fault

I wrote about the geology that leads to these great risks we are facing in a story called “Multiple geologic forces make region vulnerable to quakes.” I also wrote about an early-warning system being developed to give people a brief notice of severe shaking, which could be enough time to save lives.

In the matter of the early-warning system, President Obama’s proposed budget to Congress, released Tuesday, includes $8.2 million for the early-warning system. See the news release from Sen. Patty Murray and Rep. Derek Kilmer.

A good explanation about how people might benefit from the early-warning system is provided by Richard Allen in a presentation Feb. 2 in Washington, D.C., called “The Resilience Summit.” This issue is discussed in a YouTube video from 7:40 to 14:00 minutes into the video.

Another video, below, provides additional details about the design of the early-warning system and how it would function in the Los Angeles region. Called Shake Alert, the project has its own website. The Pacific Northwest Seismic Network is a key part of the project.

Thinking about tsunamis here in the Northwest

Reports about the loss of life and devastation in Japan are overwhelming — and yet most experts seem to consider Japan as the best prepared for earthquakes among all countries in the world.

I’ve been covering Northwest earthquake science for more than 25 years. When I heard that the Japanese quake was around magnitude 9 and sending a tsunami across the ocean toward the U.S. West Coast, I thought about an earthquake that occurred off the Washington Coast more than 300 years ago.

That earthquake sent a wall of water across the ocean, washing up on the shores of Japan. Because of that tsunami, researchers have been able to calculate the time of that quake to about 9 p.m. on Jan. 26, 1700.

I wrote a story for Saturday’s Kitsap Sun making some general comparisons between Friday’s earthquake in Japan and the last great Cascadia earthquake of 1700.

In broad-brush terms, “the two earthquakes are very similar,” John Vidale, director of the Pacific Northwest Seismograph Network, told me. “As a first guess, what might happen here is what happened there.”

For Saturday’s piece, written for a general audience, I decided to avoid some of the technical details about the two earthquakes, so allow me to offer some additional information here:

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What to do when you live in earthquake country

Last week, I completed a reporting project focused on earthquake preparedness. With recent earthquakes throughout the world fresh in people’s minds, I thought it would be a good time to remind readers about what to do before, during and after an earthquake. After all, Western Washington is considered one of the most active earthquake regions in the United States, if not the world.

Hazard maps are used by structural engineers to design buildings to withstand extreme shaking of various kinds. This map depicts maximum ground acceleration (measured in gravitational pull) from an earthquake with a 2 percent chance of occurring in the next 50 years. (Click to enlarge)

This isn’t so much a water issue — except that families should store at least three gallons of water for each family member . But I wanted readers of Water Ways to know that the Kitsap Sun now has a Web page that will remain in place for people to get basic information about earthquakes. It’s easy to remember: kitsapsun.com/earthquakes.

A special piece of that page is an interactive map linked to a timeline of major earthquakes throughout history in the Northwest. Putting all those earthquakes on a single map would have created an unreadable clutter. Instead, only a handful of earthquakes appear at any time as you scroll through the timeline. Thanks go to our web editor Angelia Dice and technical wizard Brian Lewis for putting this map together and making sure it works right.

This earthquake page is meant to supplement ongoing information provided by Washington State Emergency Management as well as local emergency management agencies. These agencies will coordinate official information during a disaster, as news goes out on all forms of media that can get up and running — radio, television, websites and print. At the Kitsap Sun, we are thinking about our role in helping average people cope when things start going a little crazy — as we can expect one of these days.