Report: West Coast not prepared for tsunami

Report: West Coast not prepared for tsunami
A tsunami advisory was in place in Florence in 2009.

SEATTLE (AP) — More than six years after the Indian Ocean tsunami shocked the world with its deadly power, communities along the West Coast of the United States remain ill-prepared for a similar event, concludes a report from the National Academies of Science.

An earthquake on the offshore fault called the Cascadia subduction zone could send waves crashing to the shores of Washington, Oregon and Northern California within minutes — not enough time for local authorities to issue warnings or evacuate, said John Orcutt, the University of California, San Diego, seismologist who led the review.

"That's what happened to Bandeh Ache (in Indonesia), and the disquieting thing is that it could happen to us," he said.

The only way to prepare people for such a fast-moving disaster is to deeply ingrain a simple message, Orcutt said: When the ground shakes or the water pulls back from the shore, walk uphill as quickly as possible.

States and local communities have undertaken education programs to spread that message, but results are uneven and approaches vary widely. In some towns, local residents removed tsunami evacuation signs because they didn't want to scare off tourists, Orcutt said.

The report recommends a more uniform approach in terms of signs, warning messages, educational approaches and risk assessment.

"You need good coordination to deal with tsunamis," added Oregon State University civil engineering professor Harry Yeh, who served on the review committee. "These kind of events are not local business - they're everybody's business."

The analysis was requested by Congress, which boosted funding for ocean buoys and tidal gauges after the 2004 Indian Ocean tsunami. Today, a network of 39 buoys stretches from Alaska to South America, capable of detecting tsunami waves as they pass.

But the high-tech instruments are mainly useful for tsunamis generated by distant earthquakes - off the coast of South America, for example. In that case, several hours of warning time would allow for evacuation of coastal communities, Orcutt said.

But nearly a third of the buoys are out of service at any time due to malfunctions, Orcutt said. "That's a very, very large number." The report recommends that the National Oceanic and Atmospheric Administration, which runs the buoy network, beef up maintenance or design hardier instruments.

The committee also called on NOAA's Tsunami Warning Centers in Hawaii and Alaska to better coordinate their efforts. The centers currently use different computer systems and different software, and are not able to back each other up, Orcutt said. After an offshore earthquake in 2005, the centers issued conflicting and confusing warnings that led to panic in some communities and complacency in others.

Tsunami awareness has increased tremendously since the Indian Ocean disaster, Yeh said. But with federal funding already dropping, it's not clear how long that awareness will last.

"Tsunamis are rare events," Yeh said. "What's going to happen 20 years from now? One hundred years from now?"

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Information from: The Seattle Times, http://www.seattletimes.com


 

Copyright 2010 The Associated Press.