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Utah Geological Survey
January 29, 1996
Study Details Potential for
Farmington Landslides
A 7 square mile area of northern Davis County near Farmington, known as the Farmington Siding landslide complex, contains some of the largest landslides triggered by earthquakes in the United States. The complex is made up of several individual, prehistoric landslides. A new study by the Utah Geological Survey reports this area, prime for future development, could be at risk from future landslides.
"Research indicates that the slides were associated with earthquake-induced liquefaction at many times in the past," said geologist Michael Hylland. Liquifaction occurs when soil loses strength and behaves as a liquid (such as quicksand) rather than as a solid. "We see evidence of landslides on gentle slopes not normally prone to sliding. It appears high levels of Great Salt Lake and associated ground water, such as occurred in 1873 and again in the 1980s, may increase the potential for liquefaction-induced landsliding during a large earthquake," he added.
Although the Farmington Siding landslide complex is in a largely rural area, it is crossed by state and interstate highways, railroads, and petroleum and natural gas pipelines. Also, continued population growth along the Wasatch Front increases the likelihood of development within the area.
The authors of the report, Michael Hylland and Mike Lowe, recommend that site-specific
geotechnical-engineering studies be completed to facilitate wise land-use
planning.
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