Bad as it will be whenever the Cascadia Subduction Zone next comes unstuck, there are steps we can begin taking now to ensure most outer coast residents survive to pick up the pieces.
This is the goal of new design standards for tsunami-safe buildings that were unveiled Wednesday in Portland at the American Society of Civil Engineers’ annual meeting.
Up until geological discoveries in the 1990s, the Pacific Northwest didn’t have many natural disasters to fret about other than volcanic eruptions. Then we learned that European-American settlement happened to occur during one of the centuries-long lulls between massive earthquakes and the tsunamis they spawn.
Humans adapt to danger and residents of low-lying communities along the Washington and Oregon coast have reacted with a kind of optimistic fatalism — figuring it’s unlikely to happen in any one person’s time here, but if it does there’s nothing that can be done other than bow to the whims of fate.
“In some places, like Washington’s Long Beach Peninsula or Ocean Shores, even the fleetest runners could never make it to safety in time and few — if any — buildings are likely to survive the wall of water that will hit after the shaking stops,” the Seattle Times reported Tuesday in a story about an ASCE subcommittee’s ideas for better coastal buildings. (See www.tinyurl.com/Tsunami-Safe-Buildings.) In our area, this danger also looms from Warrenton to Cannon Beach, and even hangs over Columbia estuary cities including Astoria, Ilwaco and Chinook.
“That grim outlook inspired a group of leading engineers to create the nation’s first design standards for tsunami-safe structures,” the Times reported. “If incorporated into building codes as the engineers hope, the standards would require that new, critical facilities like hospitals, police stations and schools in vulnerable areas be strong enough to withstand the tsunami and tall enough that occupants won’t be swept away.”
“We’re basically trying to save lives,” one of the engineers said. “The idea that you would essentially write off whole communities is not acceptable.”
The ASCE’s Gary Chock points out that some Japanese buildings saved tens of thousands of lives during the 2011 tsunami, permitting residents to ride out the flood in structures made to remain standing despite powerful earth shaking, and pummeling by seawater and debris.
In the U.S., the first similar building — the gymnasium at Ocosta Elementary School near Westport, Washington — was dedicated this summer, with room on the roof for 2,000 quake survivors.
Such multi-functionality is essential, providing an asset that will be used by community members every day, hopefully for decades before it is needed to escape a tsunami. This contrasts with plans for expensive evacuation platforms in planning stages on the Long Beach Peninsula, designed with little else in mind besides briefly getting school children above harm’s way.
Some building groups object the tsunami-safe standards will be too expensive, but the civil engineers’ group calculates only a 1 to 3 percent increase in cost. The standards would only apply to important public buildings, not to homes or private businesses.
Estimates of when a subduction quake and tsunami will happen are imprecise. Disaster may strike this afternoon or a century from now. With a little luck, we may have several generations to build survivable buildings. Civic leaders, planners and architects now have a good starting point — thanks to the Society of Civil Engineers — for constructing multi-purpose structures that will provide decades of service before they are needed to escape the ocean’s onrushing waters.
Every coastal community, every school board, every hospital district and government agency — including the U.S. Coast Guard — should adhere to tsunami-safe building codes from this point forward.