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7.1.5: The Nisqually Earthquake

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    At $2 billion, the Nisqually Earthquake was the most costly natural disaster in the history of Washington State. Insured losses were $305 million, about 15 percent of the total. Losses included not only damage to structures but damage to contents and loss of data. Twenty-one percent of businesses had earthquake insurance but most of their direct losses were less than their deductible, typically 10 percent of the value of the building and contents. For those businesses with losses greater than $10,000, about half received earthquake insurance payments. Most small businesses repaired their damage without insurance payments.


    Less than one-third of Washington homeowners have earthquake insurance. Safeco, the second-largest issuer of homeowners’ insurance, includes earthquake insurance on only 8.5 percent of its policies, although this figure is 13.5 percent in King County. The average Safeco earthquake insurance policy cost $390 per year before the earthquake. Immediately after the earthquake, insurance companies placed a moratorium of thirty days on writing new policies. The principal reason was to guard against people who had suffered damage in the earthquake obtaining an earthquake policy after the fact.


    In summary, and in contrast to the Loma Prieta and Northridge earthquakes in California, the insurance industry came through the Nisqually Earthquake in good financial shape, even though the urban area affected was about the same. The reasons for this were (1) Nisqually was a deep earthquake, and shaking intensities were lower, and (2) the risk exposure was less than it would have been in urban California; fewer people had earthquake insurance.

    7.1.5: The Nisqually Earthquake is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Robert S. Yeats via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.