OCEAN SHORES, Wash. -- The sign in front of the stone entry to this beach town says, "TsunamiReady Community." But Ocean Shores is ill-prepared to face the onslaught of waves that would be spawned by a big quake from a major fault zone just offshore.
Forecasters estimate there would be only about 15 to 25 minutes to flee. While the sign advises people to move to higher ground should the earth start trembling, many roads leading to safety would likely be impassable due to downed bridges and other quake damage.
"Your best fighting chance is to get out on foot, and for some in these communities, that would be highly unlikely. There just wouldn't be enough time," said Nathan Wood, a U.S. Geological Survey researcher who has studied tsunami risks in the Pacific Northwest.
The precarious plight of coastal residents in Pacific and Grays Harbor counties is detailed by Project Safe Haven, a federally funded effort by the University of Washington, state, tribal and local officials.
The researchers are mapping areas where people would be unlikely to reach high ground, and working with residents to plan a network of towers, berms or other structures that could be built as refuge from the floodwaters.
The risk to these communities results from an unfortunate mix of geology and geography.
The Cascadia Subduction Zone, a point of tremendous pressure where one of the Earth's plates dives under another, sits just off the Southwest Washington coast.
Geologists estimate that fault unleashes a massive quake off Washington's coast about every 500 years.
The last such earthquake, of roughly 9.0 magnitude in 1700, triggered a tsunami similar to the one that devastated coastal communities of northeast Japan in March.
"The most vulnerable community"
About 40,000 residents live in tsunami-prone stretches of a four-county area that wraps around the outer coast and into the Strait of Juan de Fuca, according to a U.S. Geological Survey study completed in 2008.
Researchers estimate that roughly a quarter of those residents may not be able to walk to high ground in the time between an offshore earthquake and the first tsunami wave, according to Wood.
At Ocean Shores, up to 30 feet of water could inundate all but a few slivers of high ground on the six-mile-long peninsula the city is built upon.
In the aftermath of a quake, many people likely would be isolated by downed bridges that cover an extensive network of lakes and canals in the city of more than 5,500 residents.
"Ocean Shores is the most vulnerable community on the coast; I don't think there is any close neighbor," said Tim Walsh, chief hazards geologist with the state Department of Natural Resources.
Walsh said that the reassuring "TsunamiReady" sign was developed by the National Weather Service, signifying that the community has marked evacuation routes and met a series of other benchmarks.
Ocean Shores was the first community in the nation to get that certification. But the 2001 ceremony marking the occasion was disrupted by a protester saying the sign gave residents a false sense of security.
The team also came up with some initial construction costs. A proposed berm, reinforced with rock walls and big enough to accommodate 1,000 people, could be built for $706,000. Towers, their height dependent on where they were built, could hold 100 people. The estimated cost for those is $107,000.
The structures would be built to meet federal tsunami standards first published in 2008. Towers would be girded with rock to divert debris. They could also have stairways that would enable wheelchair access before breaking away in the floodwaters.
Some here wonder what would happen if the earthquake struck during a summer day, when the city population may more than double in size with tourists. Would there be enough room for everyone scrambling for safety?
What about the disabled still living in their own homes but unable to leave by themselves? Would people risk their own lives to help them out?
Others wondered if such structures would be built in time for the next big tsunami.
"We are a time bomb here," said resident Judy Dawson. "We just have to hope it's not our time yet."
Hal Bernton: 206-464-2581
(Distributed by Scripps Howard News Service, www.scrippsnews.com)