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Leading the effort to mitigate the tsunami risks are university researchers and government officials working together with local residents. Jay Raskin, an architect involved in the project, and Harry Yeh, Oregon State University engineering professor, note that the effort conforms to new guidelines put forth by the Federal Emergency Management Agency (FEMA) for the design of structures for "vertical evacuation" from tsunamis, an approach in which people will move to the upper levels of a fortified building to escape the tsunami flood rather than attempting to run to higher ground. The Cannon Beach City Hall is said to be the first in the nation to implement these structural guidelines.
In order to meet the stringent requirements and be an effective tsunami evacuation structure, Cannon Beach City Hall will have a deep foundation in order to withstand the earthquake prior to the tsunami as well as the erosion by the wave. Furthermore, the structure will need to be two stories high and have a flat roof for additional evacuation, if needed. According to Raskin, the finished building is designed to save 1,000 to 1,800 residents of Cannon Beach in the case of such a disaster. The number of lives saved could be even higher during the summer months due to the tourist activities in the area.
On the current time line, Cannon Beach City Hall is expected to be completed by March 27, 2014 to mark the 50th anniversary of the 1964 Great Alaskan tsunami, which killed four people on the Oregon coast. Together with the implementation of the All Hazard Alert Broadcast system (AHAB), an early electronic tsunami detector off the Pacific coast, the building will provide enough time for coastal residents to find refuge. But Robert Freitag, an expert in the Cascadia Region Earthquake Workgroup at the University of Washington, says it might not be enough. Despite the AHAB warning system in place and greater public awareness, "there are still areas with no or few escape possibilities."
Despite the benefits having tsunami evacuation structures, there are a still few issues that remain to be solved. In order to be an effective safe house, the structure must remain open in both day and night. Security could be difficult to manage due to increased chances of vandalism and crime. Furthermore, keeping the cost of such structures down will be crucial to wide adoption of these facilities. In the case of Cannon Beach, the structure will cost twice as much as an ordinary building, according Raskin. "Our preliminary cost estimates for the conceptual design show that a standard wood framed City Hall built to current code would cost about $2 million and that the raised building with the roof terrace would cost about $4 million." Funding for this project is shared equally between local and state/federal sources.
The Cannon Beach City Hall is a step forward in the fight against tsunami risks, but more efforts and funds will be needed to bring the rest of the Pacific Coast up to par. No one knows when the next great earthquake will hit, but the need for an evacuation structure remains clear as the possibility of a tsunami looms.
Ken Su is currently an undergraduate student in economics at the University of Washington.
Image: Future Cannon Beach City Hall
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