Earthquake experts tend to agree that it is not a matter of “if” the west coast will experience another major seismic event, it is a matter of “when” that will happen. Though it is impossible to know for sure how long west coast residents have to prepare, safety experts also agree there are far too many buildings on the coast that will likely not withstand the damage from a significant earthquake, putting the lives of the people in and around them at risk.
One building collapsing on its own can have catastrophic consequences and a high number of injuries or fatalities, but many buildings collapsing in one incident would result in overwhelmed hospital emergency rooms and rescuers being diverted from other urgent situations.
California Legislature Wants List of Vulnerable Buildings
Buildings that are at risk of collapse can be retrofitted to make them safer in the event of an earthquake. In an attempt to get the ball rolling, the California Legislature has sent a bill to Governor Jerry Brown, which would require jurisdictions at the highest risk of a significant earthquake to list their buildings most vulnerable to substantial damage or collapse.
Bill AB 2681, written by Assembly Member Adrin Nazarian, requires all cities and counties located in seismic zone 4 to identify “all potentially hazardous buildings and to establish a mitigation program for these buildings” by January 1, 2021. Potential mitigation programs include plans to strengthen the buildings or adopt a hazardous buildings program. The owners of potentially vulnerable buildings would be required to hire a professional engineer to determine how susceptible the structure is and provide a report to the jurisdiction’s building department. If the engineer’s report finds the building is not vulnerable, the building is pulled from the list.
According to the Los Angeles Times, some cities in California have already developed their own lists of buildings at risk of collapse, with a few even requiring owners to retrofit their vulnerable buildings. Not all of those cities, however, took action on their list. Some have not even warned residents about the structures. Meanwhile, the newspaper reports, the California building collapse bill does not provide funding for the project. Without funding, the most the list may be able to offer, is to give California residents information about the structures they live and work in.
Experts Predict Staggering Costs Associated with the Next Big Earthquake
Bill AB 2681 notes that a recent California ShakeOut study estimates that a major earthquake involving the San Andreas Fault could cost more than two hundred billion dollars—including physical and economic damage. That same study estimated an earthquake could cause as many as 1,800 deaths.
“California contains thousands of buildings that are known to present an unacceptably high earthquake risk of death, injury, and damage based on their age, structural system, size, and location,” the bill states.
Organizations such as the Seismic Resilience Initiative and the U.S. Resiliency Council urged Gov. Brown to sign the bill and put it into effect. The groups noted that the bill would create a valuable resource and begin conversations about saving lives when a big earthquake hits. Furthermore, cities will have the information they need to plan for emergency resources in a massive earthquake.
Los Angeles and San Francisco have Thousands of Vulnerable Buildings
Logically, the largest cities will have the highest number of at-risk buildings. Los Angeles reportedly has approximately 15,000 vulnerable buildings, while San Francisco has around 5,000 vulnerable wood apartment buildings. Both cities require the building owners to retrofit their structures, following in the footsteps of Santa Monica, which was the first California city to require retrofits.
San Francisco is no stranger to earthquake devastation. A 7.9 magnitude earthquake hit the Bay Area in 1906, destroying 80 percent of San Francisco’s buildings and killing almost 3,000 people. Another 300,000 were left without homes. More recently, an earthquake in 1989 killed more than 60 people. Currently, experts are concerned about approximately 40 high rises in downtown San Francisco that were built using a flawed construction technique that could make them vulnerable to collapse.
Additional Bill Requires Examination of New Construction Standards
Another California building collapse bill, also written by Assembly Member Adrin Nazarian, requires a committee be formed to determine whether new construction should face stricter building earthquake standards. Bill AB 1857 requires the working group to determine whether new buildings should be held to a “functional recovery” standard in which they must be built to be usable following an earthquake or constructed so they can be restored to support their basic intended functions in an acceptable time.