Disaster Highlights 2007 0709 v2

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ABAG Earthquake and Hazards Program Local Hazard Mitigation Plan - Mitigation Policy Review Single-Family Homes in Earthquakes - Risk Management and Public Policy Opportunities What are the risks facing single-family homes associated with earthquakes? Structural damage is the largest earthquake-related risk facing single-family homes. The amount and type of potential structural damage that a home faces depends upon the type of construction, its age and condition, and its location. The highest risk homes include: . Unretrofitted homes built before 1978 (these were constructed prior to the adoption of the most important earthquake-resistant building code changes). . Homes on hillsides . Homes with living space above a garage (these are subject to collapse due to structural weaknesses due to the garage door openings). While no home is earthquake proof, much of this risk can be reduced by identifying the risks to a home and conducting a proper retrofit of the home. Nonstructural damage includes risks posed by falling furniture and other objects, as well as risks posed by fires after an earthquake. . Water heaters pose fire risks if they fall over during an earthquake. The California Health and Safety Code requires that all new or replaced water heaters be braced to a wall in order to prevent collapse. . Leaks (gas or water) caused by broken pipes pose fire and flooding risks to the home. . Chimneys present collapse hazards even if they are braced. Porches and other nonstructural elements may collapse and should be retrofitted or replaced. . Furniture or heavy objects can cause injury if they fall on a person during an earthquake. What happens when homes are destroyed in an earthquake? When homes are destroyed by an earthquake, it affects the functioning of the entire city, not just one department. While it may be only the structural elements of the home that cause a home to collapse, the resulting collapse can tax all local services. Emergency responders may need to provide life- saving services. Local hospitals may need to treat injuries of inhabitants. Temporary shelters will need to be established to provide for up to 160,000 residents across the region. All of these problems will be exacerbated by the fact that people with specific support needs (including the poor, elderly, and disabled) will be affected more than the regular population, expanding the need for local supportive services. 350,000 l!! ~ 3OO,OOOk----~-- ~ 2S0,OOO ~,-\-----~---~ c ' - I ~ 2110,000 ,-- - .. 0- S i \ Go I so,ooo r _.H \--- '0 ' 1: 100,000 ~ sO,ooo z . Kobe -- The Hayward Earthquake "Nightmare" - Nonhrtdge o o 3 4 Month 6 As shown above, people will need emergency shelter for months after a major earthquake. In the long-term, the cities' economy will be affected by the loss of housing for workers and the property tax dollars associated with damaged homes. Increased prices of building materials and services caused by a surge in demand will provide a boon to the construction industry, but will affect other industries negatively as people will lack the money to spend on other goods. Therefore, the efforts that local governments make to prevent structural damage to homes will have positive long-term consequences for the functioning of the entire city and the well-being of all residents of the city.