San Mateo County Earthquake Hazard

The Peninsula portion of the San Andreas Fault poses the largest risk for San Mateo County, passing through the center of the county. The Northern San Gregorio fault also passes through the western edge of the county. The San Andreas Fault has a 21% chance of creating a magnitude 6.7 or greater earthquake in the next 30 years.

The last earthquake with a magnitude over 5.0 with an epicenter in San Mateo County was the 1957 Daly City earthquake with a magnitude of 5.3. While the epicenter of the magnitude 7.8 earthquake in 1906 on the San Andreas Fault was not located within the county, it still caused extreme ground shaking and a similar earthquake in the future will likely do the same, especially in the heavily populated Bayside, much of which is underlain by alluvial deposits, Bay mud and artificial fill. A rupture along the peninsula will cause extremely violent ground shaking throughout the county. The Bay margins will also be likely to experience liquefaction in a major earthquake.

San Mateo County Hazard Map

San Mateo San Andreas San Gregorio
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Locate the area where you live and click to determine the most damaging earthquake scenario for your area.
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How were these scenarios determined?

Source: USGS, 2013

Learn How an Earthquake will Affect San Mateo County

Housing losses
Transportation losses
Water/wastewater system disruptions

Resources for Local Governments

Hazard mitigation grants for local governments
On Solid Ground – How good land use planning can prepare the Bay Area for a strong disaster recovery, SPUR 2013

Resources for Residents

Local government recovery toolkit
Family Emergency Planning Guide

What Other Hazards Affect San Mateo County?

Climate Change
Last updated: 07.21.2014