Playing 'Sim-tsunami': Wave slams a miniature Seaside in OSU exercise

Story Posted: Mon, Sep 17, 2007

A Register-Guard Editorial
Published: Monday, September 17, 2007

Yes, it could happen here. And, yes, it will sooner or later.

Nothing even remotely approaching the 2004 Asian tsunami, which killed more than 230,000 people, has visited the Northwest coast in recent history, but that doesn't mean it isn't vulnerable.

In recent decades, scientists have uncovered evidence that the Northwest has been slammed before by magnitude 9 earthquakes and tsunamis. The last was in January 1700. The next? It's anyone's guess.

The Register-Guard's Winston Ross recently reported efforts by Oregon State University scientists to simulate what would happen if a major tsunami, the kind that occurs only every 300 to 500 years, struck Seaside.

A demonstration at OSU's O.H. Hinsdale Wave Research Laboratory, the most sophisticated tsunami research facility in the nation, was soberingly realistic. Researchers created what would be a 35-foot wave in real life, and reporters watched as it rammed into a scale model of the city's landmark beach-front promenade and then inundated the hotels, businesses and homes behind it.

The aim of the exercise was not to frighten Oregonians, although that might not necessarily be an undesirable outcome. The researchers are exploring how water from a tsunami would channel through a coastal city - and at what depths and speeds. They also hope to learn more about the destructive movement of debris and to determine whether people fleeing a tsunami might be safer in tall buildings, perhaps vertical shelters such as those constructed for evacuation purposes in Japan, rather than attempting to reach higher ground.

The research project has extra significance in the wake of last week's powerful earthquakes and a 10-foot tsunami in Southeast Asia. They occurred in the same area that produced the 2004 quake and that has a subduction zone nearly identical to the 750-mile long Cascadia Subduction Zone off the Northwest coast.

For longtime Oregonians, Northwest Coast tsunamis are more than a laboratory exercise. In 1964, Florence, Seaside and other Oregon coastal communities were hit by a tsunami caused by a 9.2 magnitude quake in southern Alaska. The wave killed four children at Gleneden Beach in Oregon and 11 people in Crescent City, Calif.

Scientists can't predict the timing of earthquakes. But they do know there will be another one some day on the Northwest coast, and Oregonians should benefit from the work that OSU researchers are doing to prepare for that grim eventuality.