Planning for the 'Big One'—In Salt Lake City

Many people outside of Salt Lake City might not realize that the city's proximity to the Wasatch Fault puts it at risk for an earthquake likely in the range of 7.1 on the Richter scale.

1 minute read

October 1, 2015, 2:00 PM PDT

By James Brasuell @CasualBrasuell


Henry Grabar reports on the ongoing work of the Utah Geological Survey (UGS) to "to determine the history (and the ongoing potential) of earthquakes in the West Valley fault zone," where Salt Lake City is located. The question they hope to answer: Is Salt Lake City ready for the "Big One."

The "big One" is expected to occur along the Wasatch Fault. "According to a study [pdf] released this summer by the Utah chapter of the Earthquake Engineering Research Institute, “big ones” on the Salt Lake segment of the Wasatch Fault tend to occur every 1,300 to 1,500 years. The last one occurred 1,400 years ago," writes Grabar.

There are also smaller faults just across town, which the UGS is still studying to learn more about their relationship to surrounding faults.

The crux of all this study to those in the planning profession: the research is intended to produce a model of the "degree of ground shaking" in an earthquake. According to Grabar, "Research like this provides the backbone of the municipal codes that dictate how apartments, roadways, transit lines and virtually everything else in the city must be built — or should be renovated."

Tuesday, September 29, 2015 in Next City

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