ASTORIA, Ore. - Nearly one year has passed since the devastating Sumatra earthquake and tsunami and despite that stunning wakeup call, Pacific Northwest residents are ill-prepared and even dismissive of the danger presented by the offshore Cascadia Subduction Zone.

During the last 10,000 years, there have been at least 23 earthquakes of magnitude 8.5 or higher off the Northwest coast, scientists say, and the threat from a major event and subsequent tsunami is very real - and probably overdue.

Yet education and outreach efforts have met with mixed results that vary individual by individual, and community by community, says Patrick Corcoran, coordinator of the Oregon State University's Sea Grant Extension Coastal Storms Program.

"People tend to either be dismissive of the danger, or fatalistic about it," he said. "Both are exactly the wrong approaches to take."

During the past several months, Corcoran has begun working with coastal communities in Oregon and southwest Washington to educate them about the danger of a subduction zone earthquake and tsunamis. Scientists say the Cascadia Subduction Zone is remarkably similar to the terrain in the Indian Ocean that led to the 2004 Sumatra quake and such devastation could occur in the Pacific Northwest.

Though some education progress has been made in a general sense, Corcoran says, people still don't know enough about how earthquakes and tsunamis could directly affect them.

"If you live in tornado country, you know to get into your basement with your radio and ride it out," Corcoran said. "You do it every year. But people living along the coast for the most part have no idea if they're in the inundation zone, they have made no plans on evacuating the family, and they haven't even identified a meeting place. In short, few families have any kind of communication plan."

Though signage along the coast has improved and siren systems have been installed, too many residents are unaware of what would happen should an earthquake and tsunami strike, Corcoran says.

"The general scenario played out is that a disaster would happen at 6 p.m. with the family gathered around the dinner table," he said. "No one thinks about what to do if the kids are at school, or Mom is running errands on the other side of a river over which lies a bridge that will collapse. There is a general feeling that someone will come to the rescue. But in a full-scale disaster as we saw in New Orleans with Hurricane Katrina - that may be some time."

In his presentations, Corcoran emphasizes the difference between a subduction zone earthquake, which occurs where tectonic plates collide, and crustal quakes, which are more frequent but usually less severe. He also differentiates between a distant earthquake - near Alaska or Japan, for example - that would give Northwest residents a few hours to evacuate, and a local event that may send a 60- to 90-foot surge of water inland within 30 minutes.

Though much of the attention has focused on tsunami preparedness, Corcoran says, few people think about the potential impact of a local magnitude 9.0 earthquake.

"People should not expect emergency services following a major earthquake," Corcoran said. "Local emergency responders will be overwhelmed and it will be difficult for others to help us. First, Highway 101 will be closed in hundreds of places because of earthquake-induced landslides, bridge failures and inundation damage, and major east-west highways would likewise be closed.

"Portland and the valley, being inland, would still be affected by the earthquake and have their own problems to address," he added. "It might be a few - to several - days before rescue efforts could reach local residents at the coast."

Corcoran says it is impossible for coastal communities to totally prepare for such a nightmare scenario, yet there are some things they can do that would help. One would be to publicize the location of assembly areas where evacuees should gather after a local earthquake.

"People need to know where 'safe' is," Corcoran said. "We have lots of signs telling us where to flee from, but no information on when to stop."

Communities also can continually educate themselves about earthquakes and tsunamis, focusing on the differences between distant and local events. Siren warnings, Corcoran says, should not be a cause for panic because they signify a distant event and local residents have time - often hours - to prepare.

"People who think sirens mean that tsunamis are imminent are dangerously misinformed," Corcoran said. "These are the people who jump into their cars and may cause accidents. A major local earthquake, on the other hand, is the warning that a tsunami may hit in as little as 15 to 30 minutes."

A third thing communities can do, Corcoran says, is to encourage families to develop a communication plan. During a distant event, phone lines may be jammed, causing inconvenience and stress. Families with homes in the inundation zones may not be able to return to them.

"A pre-determined meeting place would be very useful," Corcoran said. "During a local event, families need to understand that everyone will be on their own. They need to get themselves to safety first, and do not enter an inundation zone. Call a non-local relative and let them know you're okay."

Families and individuals, Corcoran said, should follow some simple guidelines:

 

  • Identify the "inundation" zones in your community, so you know where high water will hit, as well as the "safe" zones where you need to get to;

     

  • Develop a communication plan for your family - and even friends and neighbors - that includes agreement on local meeting place, and a distant relative or friend you can call if you get separated;

     

  • Educate children about what to do in an earthquake and tsunami, especially if they are away from home. Know where your children are taken in an earthquake during school hours.

    "Disaster kits may be helpful, but I'd suggest learning first aid and CPR," Corcoran said. "Knowing how to use a T-shirt to make a bandage is more useful than having an emergency bag you don't know what to do with - or is under the rubble that used to be your garage. And simply buying an emergency kit can lead to complacency and a feeling that you have things covered when you do not."

    It is up to individuals to take care of themselves and their families, Corcoran said. Local authorities cannot possibly help everyone at the same time following a local event. Don't anticipate that organized help will immediately and magically appear, he added.

    "There are no nannies during a major earthquake and tsunami."

  • Source: 

    Patrick Corcoran, 503-325-8573

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