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 Death and Injury - Death and injury can occur both inside and outside of buildings due to collapsed buildings and falling equipment, furniture, debris, and structural materials. Downed power lines and broken water and gas lines can also endanger human life. Damage to transportation infrastructure or debris on roadways may result in multiple vehicle crashes. Fire - Downed power lines and broken gas mains can trigger fires. When fire stations suffer building or utility damage, quick response to extinguish fires is less likely. Major incidents will demand a larger share of resources, and initially smaller fires and problems will receive little or insufficient resources in the initial hours after a major earthquake event. Loss of electricity and broken water mains may cause a loss of water pressure, further hampering firefighting ability. Buildings - The built environment, comprised of buildings, various vertical or horizontal structures used or occupied, and supporting infrastructure, is susceptible to damage from earthquakes. At best, these structures were built to remain upright during shaking long enough to afford occupants time to vacate once it is safe to do so. At worst, buildings can collapse, trapping or burying people. Many lives may be at risk and the cost to repair the damage can be great. Santa Ana is one of the original communities in Orange County and has a substantial number of buildings built before 1933 (the year of the Long Beach Earthquake) and before 1994 (the year of the Northridge Earthquake), which may be susceptible to major earthquake damage. These were pivotal years as they marked the origination and improvement of seismic safety standards that are enforced today. In the late 1970's, the City performed a survey to tag and mitigate hazards posed by the most dangerous type of structure, unreinforced masonry (URM) buildings. 209 buildings were tagged and were either seismically retrofitted to afford occupants more time to vacate, or were demolished. Many of these structures are concentrated in the downtown area. With the older construction existing in the City, a significant number of structures remain at risk, including concrete tilt -up buildings, homes on raised foundations, soft -story structures and pre-1970 non -ductile multi -story concrete structures. Robust application of current building codes and proper inspection of buildings is vitally necessary to protect against loss of life and property. Infrastructure and Communication — These lifelines are the connections between communities and outside services. They include water and gas lines, transportation systems, electricity, and communication networks. Ground shaking and ground failure can cause pipes to break open, power lines to fall, roads and railways to crack or move, and radio and telephone communication to fail. Disruption to transportation makes it especially difficult to bring in emergency supplies or services. Lifelines need to be usable after earthquakes to allow for rescue, recovery, and rebuilding efforts; to relay important information to the public; and to restore businesses and commerce. Residents commute frequently by automobile and public transportation such as buses and rail. An earthquake can damage bridges and roads, hampering the normal movement of people and goods and preventing emergency response efforts. Damaged infrastructure strongly affects the economy of the community because it disconnects people from work, school, food and family, and separates businesses from their customers and suppliers. Bridge or Overpass Damage - Even modern bridges can sustain damage during earthquakes, leaving them unsafe for use. Some may fail completely due to strong ground motion. Bridges are a vital transportation link as even minor damages can make some areas inaccessible. Because bridges vary in size, materials, location and design, any given earthquake will affect them differently. Bridges built in the 1970's or before have a significantly higher risk of suffering structural damage during a moderate to large earthquake compared with those built after 1980 when design improvements were made. Much of the interstate highway system was built in the mid to late 1960's. The bridges in Orange County are state, county or privately owned (including railroad bridges). Cal Trans has retrofitted most bridges on the freeway systems; however, there may still be some locally- or privately -maintained bridges that are not retrofitted. 39