1. LOMA PRIETA EARTHQUAKE OF 1989

2. WHAT WAS IT? The Loma Prieta earthquake, also known as the World Series earthquake, was a major earthquake that struck the San Francisco Bay Area on October 17, 1989, 5:04 pm. It was caused by a slip along the San Andreas Fault and lasted about 15 seconds. It registered a magnitude 7.1, and losses totaled about $5.9 billion.

3. THE EPICENTER The epicenter of the earthquake was in the Forest of Nisene Marks State Park, a practically unpopulated area in the Santa Cruz Mountains. The quake was named for the nearby Loma Prieta Peak.

4. CASUALTIES The quake killed 63 people throughout northern California, and injured over 3700 – 400 of which were severely hurt. The highest number of fatalities, 42, occurred in Oakland when the Cypress Street Viaduct collapsed on the Nimitz Freeway. Also, one 50-foot section of the Oakland-Bay Bridge collapsed killing one.

5. CYPRESS STREET VIADUCT COLLAPSE The upper level of a double-deck portion of the freeway collapsed, crushing the cars on the lower deck and killing 42 people. Roughly half of the land the viaduct was built on was filled marshland, and when the earthquake hit, the shaking was amplified on the former marshland, and soil liquefaction occurred.

6. OAKLAND BAY-BRIDGE COLLAPSE The bridge suffered relatively minor damage, but a 76-by- 50-foot section of the upper deck crashed onto the deck below. One car drove into the collapsed portion resulting in the death of the driver. Emergency workers had to re-route traffic, but a miscommunication directed traffic back toward the collapsed portion, and one driver plunged over the edge and smashed onto the collapsed roadbed.

7. THE WORLD SERIES The earthquake hit during the start of the third game of the 1989 World Series. Because of the unusual circumstance that both of the teams involved were based in the affected area (San Francisco Giants and Oakland Athletics)many people had left work early or were staying late to participate in after work viewings and parties. If traffic had been normal for a Tuesday rush hour, injuries and deaths could have been much worse.

8. POST-EARTHQUAKE FOOTAGE – WORLD SERIES http://youtu.be/4IfRI6VRBW0 After the earthquake hit, Jack Buck told the listening audience, "I must say about Johnny Bench, folks, if he moved that fast when he played, he would have never hit into a double play. I never saw anybody move that fast in my life.”

9. SOME FACTS The earthquake may not have released all of the strain stored in rocks next to the fault and indicates a potential for another damaging earthquake in the Santa Cruz Mountains in the near future may still exist. The fault segment that ruptured approximately coincided with a fault segment identified in 1988 as having a 30% probability of generating a magnitude 7 earthquake in the next 30 years...HOWEVER.. Calculations show that the Loma Prieta earthquake changed stresses on nearby faults in the Bay area. In particular, the earthquake reduced stresses on the Hayward Fault which decreased the frequency of small earthquakes on it.

10. This was the largest and most destructive earthquake to hit the region since the Great Quake of 1906. Liquefaction of floodplain deposits and sandy artificial fills was similar in nature to that which occurred in the 1906 San Francisco earthquake and indicated that many areas remain susceptible to liquefaction damage in the San Francisco and Monterey Bay regions. Landslides caused $30 million in earthquake losses, damaging at least 200 residences. Many landslides showed evidence of movement in previous earthquakes.

11. Approximately 16,000 housing units were uninhabitable after the earthquake including 13,000 in the San Francisco Bay region. Another 30,000-35,000 units were moderately damaged in the earthquake. The earthquake caused the flow of many streams in the epicentral region to increase. Effects were noted up to 55 miles from the epicenter. Failure of highway systems was the single largest cause of loss of life during the earthquake. The cost to repair and replace highways damaged by the earthquake was $2 billion, about half of which was to replace the Cypress Viaduct.