2007 Alum Rock earthquake 2007 Alum Rock earthquake The 2007 Alum Rock earthquake occurred on in Alum Rock Park in San Jose, California. It measured 5.6 on the moment magnitude scale and had a maximum Mercalli intensity of VI ("Strong"). The event was then the largest in the San Francisco Bay Area since the 1989 Loma Prieta earthquake, which measured 6.9 on the moment magnitude scale, but was later surpassed by the 2014 South Napa earthquake. Ground shaking from the Alum Rock quake reached San Francisco and Oakland and other points further north. Sixty thousand felt reports existed far beyond Santa Rosa, as far
Eastern span replacement of the San Francisco–Oakland Bay Bridge section was composed of a double balanced cantilever span, five through-truss spans, and a truss causeway. The original spans of the bridge east of Yerba Buena Island became the subject of concern after a section collapsed during the Loma Prieta earthquake on October 17, 1989. The replacement span is engineered to withstand the largest earthquake expected over a 1500-year period, and it is expected to last at least 150 years with proper maintenance. It had been known for over 30 years that a major earthquake on either of two nearby faults (the San Andreas and the Hayward) could destroy the