Sendai Earthquake: Is the Pacific Northwest Next?
Sendai, Japan, has just experienced a horrific subduction earthquake and tsunami arising from its proximity to the so-called “Japan Trench.” Some geologists think that Seattle and Portland have a 10 to 14 percent chance of experiencing a similar M 9.0 subduction earthquake in the next 50 years because of their proximity to the so-called “Cascadia Subduction Zone.” Such an earthquake would have a catastrophic effect on the Washington and Oregon Coast (compounded by a tsunami) and would cause major damage along the I-5 Corridor, destroying infrastructure and many buildings.
Un-reinforced masonry (“URM”), and surprisingly, pre-1994 high-rise buildings are especially at risk. There are an estimated 2,600 URM buildings in greater Portland and Seattle and an estimated 240 older high-rise buildings. Buildings such as these constitute a substantial component of the housing and commercial spaces, and contribute to the historic and cultural fabric of the respective cities.
Total preparedness is impossible, but just as individual homeowners can reduce their risk by planning, so too can the owners of at-risk buildings. Given the number and importance of such buildings to the two cities, the communities need to be persuaded to encourage seismic upgrading.
For more information, please contact the Real Estate and Land Use Practice Group or the Construction Practice Group at Lane Powell: