Item 26 - Adoption of the City of Santa Ana Emergency Operations Plan

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City of Santa Ana Emergency Operations Plan Part I Basic Plan In addition to the major faults described above, rupture of a number of smaller faults could potentially impact Orange County, including the Norwalk Fault (located in the north of the county in the Fullerton area), the El Modena Fault (located in the City of Orange area), and the Peralta Hills Fault (in the Anaheim Hills area). Undiscovered blind faults may also emerge at any time. Addressing the Earthquake Hazard In California, many agencies are focused on seismic safety issues: the State's Seismic Safety Commission, the Applied Technology Council, California Office of Emergency Services, United States Geological Survey, Cal Tech, the California Geological Survey, as well as a number of universities and private foundations. These organizations, in partnership with other state and federal agencies, have undertaken a rigorous program in California to identify seismic hazards and risks including active fault identification, bedrock shaking, tsunami inundation zones, ground motion amplification, liquefaction, and earthquake -induced landslides. Seismic hazard maps have been published and are available for many communities in California through the State Division of Mines and Geology. In California, each earthquake is followed by revisions and improvements to Building Codes. The 1933 Long Beach Earthquake resulted in the first seismic safety standards in building codes, including the Field Act requiring earthquake -resistant school construction. The 1971 Sylmar (or San Fernando) earthquake brought another set of increased structural standards. Similar re-evaluations occurred after the 1989 Loma Prieta and 1994 Northridge earthquakes. These code changes have resulted in stronger and more earthquake resistant structures. The Alquist-Priolo Earthquake Fault Zoning Act was passed in 1972 to mitigate the hazard of surface faulting to structures for human occupancy. This state law was a direct result of the 1971 Sylmar Earthquake, which was associated with extensive surface fault ruptures that damaged numerous homes, hospitals, commercial buildings, and other structures. Surface rupture is the most easily avoided seismic hazard and this Act prohibits construction atop earthquake faults. The Seismic Hazards Mapping Act, passed in 1990, addresses non -surface fault rupture earthquake hazards, including liquefaction and seismically induced landslides. The State Department of Conservation operates the Seismic Mapping Program for California. Extensive information is available at their website: http://gmw.consrv.ca. ovg /shmp/index.htm. 51