History of San Francisco

1989 Loma Prieta Earthquake

The Loma Prieta earthquake (also known as the Quake of '89) struck the San Francisco Bay Area on October 17, 1989 at 5:04pm local time. Caused by a slip along the San Andreas Fault, the temblor lasted 10-15 seconds and measured 6.9 on the moment magnitude scale (surface-wave magnitude 7.1) or 6.9 on the open ended Richter Scale. The quake killed 63 people throughout northern California, injured 3,757 and left some 3,000-12,000 people homeless.

Injuries and fatalities

Five people were killed on Bluxome Street near Fifth Street and Townsend in San Francisco as a brick facade collapsed onto the sidewalk and street. Fifty-seven of the deaths were directly caused by the earthquake; six further fatalities were ruled to have been caused indirectly. In addition, there were 3,757 injuries as a result of the earthquake - 400 severely hurt. The highest number of fatalities, 42, occurred in the City of Oakland because of the failure of the Cypress Street Viaduct on the Nimitz Freeway (Interstate 880), where a double-deck portion of the freeway collapsed, crushing the cars on the lower deck. One 50-foot (15 m) section of the San Francisco - Oakland Bay Bridge also collapsed, leading to the single fatality on the bridge.


The earthquake caused severe damage in some very specific locations in the San Francisco Bay Area, most notably on unstable soil in San Francisco and Oakland, but also in many other communities throughout the region located in Alameda, San Mateo, Santa Clara, San Benito, Santa Cruz, and Monterey counties. Major property damage in San Francisco's Marina District 60mi (97km) from the epicenter resulted from liquefaction of soil used to create waterfront land. Other effects included sand volcanoes, landslides, and ground ruptures. Some 12,000 homes and 2,600 businesses were damaged. The quake caused an estimated $6 billion ($11 billion in current value) in property damage, becoming one of the most expensive natural disasters in U.S. history at the time. It was the largest earthquake to occur on the San Andreas Fault since the great 1906 San Francisco earthquake.


Earthquake, Oakland Bay Bridge