Generations of Californians have been "putting down roots" along one of the world’s most famous faults-the San Andreas. However, few Californians have experienced a major San Andreas earthquake. In Northern California, the last major earthquake was 100 years ago in 1906. Over 3,000 people were killed and 225,000 people were left homeless. In Southern California, the last major earthquake on the San Andreas fault was 150 years ago (1857), rupturing the fault from Central California to San Bernardino. Few people lived in the area, so there was very little damage.
Further south along the San Andreas fault, from San Bernardino through the Coachella Valley to the Salton Sea, over 300 years have passed since the last major earthquake (around 1680). Another major earthquake is likely to happen on this section of the fault within our lifetime, and will shake all of Southern California. A study led by the U.S. Geological Survey describes in great detail the extensive damage and casualties that result from such an earthquake, and recommends many ways to keep this natural disaster from becoming a catastrophe.
While the San Andreas is most likely to be the source of our largest earthquakes, there are hundreds of other faults throughout Southern California that could also cause damaging earthquakes. Some may happen before the next San Andreas earthquake and could be even more destructive if they occur directly beneath densely populated areas.
This handbook is a resource for living in earthquake country. It provides information about why we should care about earthquakes in Southern California, what we should do to be safe and reduce damage, and also what we should know about earthquake basics.