Tsunami evacuation buildings: another way to save lives in the Pacific Northwest

Oct 19, 2009
This shows a conceptual design for the Cannon Beach City Hall, a Tsunami Evacuation Building (Ecola Architects, 2008). Credit: Photo courtesy of Yumei Wang, Oregon Department of Geology and Mineral Industries.

Some time soon, a powerful earthquake will trigger a massive tsunami that will flood the Pacific Northwest, destroying homes and threatening the lives of tens of thousands of people, says Yumei Wang, a geotechnical engineer at the Oregon Department of Geology and Mineral Industries in Portland.

The region's geology makes an earthquake-triggered inevitable and imminent in geologic time, Wang says, yet coastal towns and cities in the northwest are woefully unprepared for such a large-scale natural disaster. In response, she is working with public officials and stakeholders to develop a series of tsunami evacuation buildings up and down the northwest coast. They would be the first buildings of their kind in the United States. And construction, she urges, can't start soon enough.

"Unless we do this, we will have lots of people dying in a tsunami," Wang says. "That's not how we want our people to die."

Wang will present recommendations in a session titled, Risks and Realities: Current Advances in Understanding Societal Risk and Resilience to Natural Hazards, at this month's Annual Meeting of the in Portland, Oregon.

A line of volcanoes from northern California to British Columbia marks the eastern edge of a fault system (called the Cascadia subduction zone), where one plate is wedged under another. Those plates shift like geological clockwork every few hundred years, producing earthquakes that shake the region. The last major quake along the Cascadia subduction zone occurred on January 26, 1700. It produced a tsunami that damaged coastal towns as far away as Japan.

The region's next big earthquake could happen any day now, Wang says, or it might not happen for several hundred years. When the day comes, a tsunami—with inundation heights of 50 feet or more—could hit the northwest coast within 10 to 20 minutes.

This is a schematic design of a proposed Tsunami Evacuation Building (TEB). Credit: Photo courtesy of Yumei Wang, Oregon Department of Geology and Mineral Industries

The standard emergency response in cases like these is to move people inland and uphill, but there are plenty of communities where people simply won't be able to evacuate in time, Wang says. The resort town of Seaside, Ore., for example, is low-lying with inadequate roads and bridges. Kids and the elderly are particularly vulnerable.

In Cannon Beach, Ore., Wang has started meeting with officials to hold serious discussions on constructing the first tsunami evacuation building in the U.S. The building, a proposed rebuilding of the town's existing city hall, would have to be made of reinforced concrete with a deep foundation and strong columns, a post-tensioning structural system to keep it upright, an 18-foot tall first floor, and wave-dissipation structures in front and back, among many other design details.

Tsunami evacuation buildings won't be cheap. Wang estimates that the one in Cannon Beach would have an added cost of between $1 million and $2 million. But the building would provide a safe space that people could reach quickly and be ready for emergency response and long term recovery. Getting just one such building off the ground, Wang said, is a critical first step towards creating a network of buildings that will help save many thousands of lives.

More information: View abstract at gsa.confex.com/gsa/2009AM/fina… /abstract_158149.htm

Source: Geological Society of America

Explore further: Quakes destroy or damage 83 houses in Philippines

add to favorites email to friend print save as pdf

Related Stories

Could a large tsunami ever hit the United States?

Nov 11, 2005

This question gained currency after the catastrophic Sumatran earthquake and tsunami of December 2004. Nine months later interest in tsunamis was all but washed away by the deadly Gulf Coast hurricanes, Katrina and Rita.

Catastrophic tsunami possible on West Coast

Dec 28, 2004

The type of devastating tsunami that struck the southern coast of Asia is entirely possible in the Pacific Northwest of the United States, but might not cause as much loss of life there because of better warning systems, ...

Nine dead in Indonesian earthquake

Sep 12, 2007

Officials reported at least nine people were killed and more than 100 injured after a strong earthquake and an aftershock struck the Indian Ocean Wednesday.

'Clusters' of earthquakes yield an ominous scenario

Dec 30, 2004

The newest studies on the Cascadia Subduction Zone off the coast of the Pacific Northwest have identified a "clustering" of great earthquakes of the type that would cause a major tsunami, yielding a historical record with ...

Students to Test 'Tsunami Shelters'

Apr 30, 2008

Their tsunami shelters are only made out of small wooden blocks and held together by toothpaste used for glue, but they also incorporate months of study with computer-aided design, learning about engineering principles, applying ...

Recommended for you

Kiribati leader visits Arctic on climate mission

10 hours ago

Fearing that his Pacific island nation could be swallowed by a rising ocean, the president of Kiribati says a visit to the melting Arctic has helped him appreciate the scale of the threat.

NASA catches a weaker Edouard, headed toward Azores

Sep 19, 2014

NASA's Aqua satellite passed over the Atlantic Ocean and captured a picture of Tropical Storm Edouard as it continues to weaken. The National Hurricane Center expects Edouard to affect the western Azores ...

User comments : 0