Seattle’s Earthquake Preparedness

I have this semi-annoying habit (annoying to me, at least) of wanting to write about something but not doing it when I first see it. Thus, I end up with a backlog of things to write about out of the news that I think are interesting, but usually end up skipping because I’ve forgotten why I wanted to write about it in the first place.

This will probably continue to happen. But for now, I’ll write about something that’s been sitting around in my bookmarks since I saw it. There was an article in the Seattle Times on February 20th about preparing Washington State for devastating earthquakes. I wanted to react to some pieces of it.

As some people may or may not know, four years ago this month, the Nisqually earthquake hit in the Olympia area, more specifically, 6 miles north of Olympia in the Nisqually River Basin (I’ve written about this before in this entry). It caused major damage throughout the Puget Sound region, most notably in Olympia and Seattle. To this day, the Capital Dome on the Capital campus downtown is still under repair because of that earthquake. Since then, Washington has been examining its own preparedness for earthquakes — the subject of this article is an outgrowth of this examination.

The article starts with a description of the earthquake scenario created to test out the damage to Washington’s economy if an earthquake hit along the Seattle Fault:

By the time the shaking stops — 30 sickening seconds later — 1,600 people are dead or dying. More than 24,000 are injured as brick buildings crumble, freeway bridges buckle, ferry terminals slump into the water and the Alaskan Way Viaduct collapses.

More than 45,000 families are forced out of their shattered homes, and nearly 10,000 commercial buildings and houses are destroyed. Another 183,500 buildings are moderately to severely damaged.

The toll on the state’s economy is a staggering $33 billion in property damage and lost income, on a par with the country’s most costly natural disaster to date: the 1994 Northridge earthquake in Southern California.

To give readers a point of reference on where the Seattle Fault lies, here’s some further background:

The Seattle Fault is a geologic fault in the North American Plate that runs from the Issaquah Alps to Hood Canal in Washington state. It passes through Seattle, Washington just south of Downtown and is believed to be capable of generating an earthquake of at least 7.0 on the Richter scale. The Seattle Fault therefore has the potential to cause extensive damage to the city, as much of Pioneer Square and the Industrial District is built on fill, as is the downtown waterfront, which is supported by the Alaskan Way Seawall.

According to another Seattle Times article, the fault is only eight miles beneath the surface. The article further states:

The fault, also called the Seattle Fault Zone, is actually several faults in one. Unlike the better-known San Andreas Fault in California, which consists of a single fracture that parallels the coastline, the Seattle Fault Zone is at least four closely related fractures that run west to east for about 30 miles.

Beginning between Hood Canal and Dyes Inlet near Bremerton, scientists think the fault zone crosses underneath Bainbridge Island and Puget Sound before running through Seattle’s Sodo neighborhood. It continues under Lake Washington and Bellevue before ending near Lake Sammamish and north of Issaquah, said Rick Blakely, a U.S. Geological Survey (USGS) research geophysicist.

The fractures run parallel to each other about eight miles under the Earth’s surface — considered shallow by fault standards. From north to south, the faults cover less than 5 miles.

The original article goes on to examine the assembled earthquake scenario, which makes several recommendations to State authorities:

The scenario group invested three years and almost 4,000 hours of volunteer labor in the project. It recommends the state establish an independent seismic safety board that would report directly to the governor and would push for more highway retrofits and tougher building codes.

The group also is calling for upgrades to facilities such as hospitals, schools and fire stations. And it wants rules that would mandate improvements for the most vulnerable buildings — those made of unreinforced brick or concrete.

“We’ve been plodding along in Washington,” said Don Ballantyne, a Seattle civil engineer who specializes in earthquake-resistant designs and was a leading organizer of the project. “This makes it clear we’re at significant risk, and we should be working hard to manage those risks.”

The problem with this fault is that it can devastate the Puget Sound area by a number of magnitudes, far worse than the 2001 Nisqually Earthquake. The article puts this into perspective quite well, stating that "A magnitude 6.7 earthquake on the Seattle Fault would be up to eight times more destructive than the magnitude 6.8 Nisqually earthquake[…]".

Putting the total impact for the area into rather sharp relief, the article draws a picture of exactly what would happen locally if a bad earthquake struck along the Seattle Fault:

The Seattle seawall would probably crumble, taking out ferry terminals and docks. Thousands of landslides would roar down the area’s steepest slopes and slop into Puget Sound, triggering local tsunamis that could swamp waterfront homes and buildings.

Brick buildings in Pioneer Square and the Chinatown International District would tumble. Also at high risk are the scores of concrete warehouse-type buildings in the Sodo district and further south that house megastores, light industry and other businesses.

In river valleys and low-lying areas built on fill, the shaking would turn loose soils to mush, destroying foundations and breaking buried water pipes and utility lines. The Olympic Pipeline, which carries gasoline and jet fuel from northern refineries, crosses the Seattle Fault in Bellevue and passes through unstable soils in the Renton and Kent valleys.

A big chunk of Harbor Island, in the heart of the Port of Seattle, could slide into Elliott Bay, taking with it container terminals, cranes and docks.

Up to 40 percent of schools could be unusable as a result of the earthquake, and damage to hospitals could slash the number of available patient beds by 75 percent in the first days after the quake.

One of the biggest blows to the economy would be traffic snarls that could take years to unravel.

[…]

With ports and ferries crippled and highways impassible, many businesses might be forced to leave the area. To understand the impact, scenario writers looked to Kobe, Japan, where a magnitude 6.9 earthquake on a similar fault in 1995 drove business to other cities.

Even though this scenario isn’t 100% certain, it has pretty clear impacts on the state as a whole. It makes clear that Washington needs to pay attention and begin an earthquake preparedness effort to bring the infrastructure of the State up to code and prepare it for disasters.

Reaction/Analysis

The article makes it abundantly clear that the recommendations put forth as a result of this scenario need to be implemented, and this is a point that I won’t even bother to argue with — I agree. I’ve seen remnants of the damage from the Nisqually earthquake — Evergreen’s campus still has a lot of cracks in walkways in certain places where the ground settled after the quake, and the same is true throughout Olympia — and photos of Olympia and the surrounding area immediately after the earthquake showed a number of areas hit severely with damage.

I’m not sure that the recommendations go far enough in terms of accountability. The recommendation to create an advisory board reporting directly to the Governor is all well and good, but only works if the Governor decides to make earthquake preparedness a political priority. This should be statewide, but at the same time, locally coordinated efforts are likely to have far more power and far more durability. Municipal efforts in the area’s major cities — Seattle, Olympia, Tacoma, Everett, Bellingham, Bellevue, Port Angeles — organized by citizens and endorsed by municipal public works departments are likely to have a broader impact. Such an opportunity would provide for localized education about earthquake risks, what to do to prepare for an earthquake, and encourage ongoing dialogues about safety and personal awareness.

In addition, the expectation that Washington’s Department of Transportation can upgrade highways fast enough is folly. I’ll take an example from the Snohomish area — the expansion of Highway 522 between Bothell and Monroe to two lanes in both directions. Originally, between Woodinville and Monroe (about a 5-mile stretch, if my math is right), 522 spanned only one lane. Several years ago now, this was expanded to two lanes just past one of the two lights between the Woodinville/Monroe section. Now, it bottlenecks just beyond that light, and the State Department of Transportation has not had budget or support to complete the expansion. By the time the project is complete, further expansions may be required, though I don’t personally know whether the area can support additional lanes beyond the current proposed expansion.

The Highway 522 retrofit is not the only area where the Department of Transportation lacks funds to complete the project — the same is true throughout the state. Quite simply, with the ongoing statewide budget shortfall, we cannot realistically expect that any of these upgrades will occur within a reasonable amount of time. Granted, the State Legislature apparently has more money this year than they did last year, but the likelihood that any significant amount of it goes to transportation concerns seems unlikely from my standpoint.

The article is utterly and completely right — we need to be prepared. Seattle isn’t called "The Gateway to the Pacific Rim" for nothing. If that gateway collapses, it will harm far more than the local economy.

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