What’s the riskiest place in the U.S. for a natural disaster? It’s right here in Los Angeles County, according to the Federal Emergency Management Agency.
FEMA’s National Risk Index puts L.A. County atop the list for earthquake hazard, and in the top 90th percentile for wildfire risk.[i] The index, based on six years of calculations by 80 experts, was prepared to educate communities and prompt greater resilience.
The good news is that we are moving in the right direction, but there is much still to do. Unfortunately, we don’t know how much time we have until the next deadly quake strikes.
At the recent Emergency Preparedness Summit 2022 hosted by the University of Southern California Price Executive Education Forum[ii], several leaders came together to report the progress being made to reduce risk, enhance resilience, and ensure quality of life for our communities.
Speakers included: Ross Stein, Ph.D., chief executive officer of Temblor, Inc.; Aaron Gross, chief resilience officer for the City of Los Angeles; and Mark Benthien, director of communications, education, and outreach for the Southern California Earthquake Center. Tom Robinson, a former city manager and senior advisor to Optimum Seismic, moderated the panel.
Earthquakes will happen, but they don’t have to be disasters. The summit looked at how public officials and business leaders are taking action to become catalysts for change and for improving seismic resilience in the Golden State.
California has identified five types of buildings most vulnerable to damage or collapse in major earthquakes. This includes nonductile concrete buildings constructed prior to 1977, tilt-up buildings constructed prior to the late 1990s, steel frame buildings erected before the mid-1990s, unreinforced masonry buildings, and soft-story buildings constructed before 1978.
Los Angeles in 2015 enacted a seismic retrofit law requiring many of these structures to be retrofitted. As of May 1, 2022, much of this retrofit work has been completed, including 7, 764 of 12, 613 soft-story buildings.[iii] Each of these soft-story structures has a minimum of four units, representing at least 31,056 homes for some 77,640 people living in the city.
There are an estimated 100,000 vulnerable, soft-story apartment buildings housing approximately 2.5-million people in California, according to the U.S. Resiliency Council.
Risks to life and limb – not to mention economic loss and social disruption to communities – remains high in California. However, throughout the state, government leaders, property owners, lenders and insurers, environmentalists, business leaders and residents are increasingly working together to prepare communities for the inevitable threats that earthquakes bring.
Improving on building design
“We build our buildings out of stacks and cubes,” Stein explained at the summit, displaying a multi-story Tinker-Toy-like model that – like a soft-story building – rocks and collapses due to a lack of structural supports.
“The attributes of a cube is that no matter how well it’s tacked down to the surface, when an earthquake occurs, it’s basically going to move that building from side to see, and you can see it’s very weak,” Stein said, flattening the model like a collapsible tent. When he applies structural supports to the model, the structure demonstrates sheer resistance and remains erect.
A noted a scientist emeritus at the U.S. Geological Survey, fellow of the American Geophysical Union and Geological Society of America, and cofounder and CEO of Temblor, a website dedicated to earthquakes and earthquake risks, Stein said the cost of retrofitting a soft story structure is extremely cost-effective for owners of at-risk buildings.
“Our job, as scientists, is to convince people who are at risk that they need this for their building,” he said,
A 2022 study by the Bank of England calculated total losses of $750 billion from the scenario of two magnitude-seven earthquakes striking the Bay Area two weeks apart, Stein said, adding that several faults in the Los Angeles region have the capacity to strike twice.
“These are not outrageous scenarios,” he said. “They are the kind of things that insurers have to expect and plan and be ready for – and so do we.”
Resilience efforts in L.A.
A detailed scientific study determined 300,000 structures would be damaged in a 7.8 San Andreas earthquake – striking one in every 16 buildings in the region[iv].
The need to address that threat led L.A. Mayor Eric Garcetti in 2015 to sign the historic law requiring seismic retrofits of thousands of the city’s most vulnerable buildings. A short time later, the city enacted Resilient Los Angeles – a program designed to address many of the city’s looming risks, including earthquakes.
“In Los Angeles, we know a major earthquake is a matter of when, not if. And we know that the next one could be more than 10 times worse than the 1994 Northridge earthquake that claimed 57 lives, injured over 9,000, displaced tens of thousands from their homes, and caused $20 billion in damage,” the mayor wrote in a program report.[v]
Gross, the city’s chief resilience officer, said Los Angeles has been working long and hard to guard against the natural threats it faces.
“The mayor brought in (earthquake expert) Dr. Lucy Jones to develop a strategy. He brought together experts all over the region and all over the world to figure out where we should start to build resiliency, particularly on seismic safety,” Gross told participants of the USC summit.
The city created a Shake Alert app to provide early warnings for earthquakes. (That technology has since been applied statewide.) And the retrofit law is working, Gross said.
“Over half of the buildings identified as at risk have been retrofitted,” he said. “That protects against buildings falling down, saving lives and property. Also, the city is challenged with housing and these retrofits protect our existing affordable housing.”
But more needs to be done.
“Mother Nature doesn’t really care what city you live in,” Gross said. “Nature doesn’t care where the boundaries of L.A. start and the boundaries of Culver City end. We are a county of 87 cities and farther down in Southern California are another five counties. Earthquake risk is everywhere.”
Gross urged other leaders in government, business, academics and other sectors to do their part to share what has been learned to help and encourage other cities to enact ordinances of their own – noting that the impacts of earthquakes are widespread.
“A lot of residents and workers of Los Angeles work in other cities or live in other cities. We are all interconnected, and that’s important from an economic viability standpoint,” he said. “What happens after an earthquake, and how do we recover?
Southern California’s earthquake risk
There are more than 300 active faults in Southern California that can produce a magnitude 6 or greater earthquake at any time, said Benthien of the Southern California Earthquake Center.
“Some faults are vertical, like the San Andreas. Others earthquake faults are more like a broad ribbon of color – and that’s the type of fault that the Northridge earthquake happened on, including others in our past like the San Fernando earthquake of 1971,” he said. “These are faults that are dipping in the earth, and the shaking comes up from below and can shake a very broad area in unexpected ways.”
As the global coordinator of the Great ShakeOut Earthquake Drills, Benthien’s primary goal is to reach out to communities, inform them of their risks, and inspire them to take action to prepare. He presented a sneak preview of a new documentary produced by the center called “Quake Heroes,” that underscores the human aspects of earthquake risk and the dangers posed to our communities. Reenactments of the stories of the people who lived through California’s Northridge Earthquake of 1994 provide a vivid understanding of the horrors earthquakes pose. Visit QuakeHeroes.org to sign up for updates about the film.
The center also recently completed a project to anticipate the likelihood of earthquakes striking in particular areas. Like longterm weather climate forecasting, the Third Uniform California Earthquake Rupture Forecast identifies areas where larger quakes may strike in the future. This collaborative project was conducted by the SCEC, U.S. Geological Survey, California Geological Survey, California Earthquake Authority, and many universities.
Some initial findings include[vi]:
- An increased likelihood of larger earthquake events in California, and a corresponding decrease in moderate earthquakes.
- Modeling that shows the Los Angeles Region as the most likely to experience earthquakes compared to the rest of the state.
- Evidence that the Southern San Andreas Fault will be the most likely to host a large earthquake.
- An increase in the likelihood of a magnitude 8 or greater quake on the San Jacinto Fault, along with a corresponding decrease in moderate quakes.
Where do we go from here?
Following the preview of the video Earthquake Heroes[vii], Gross noted that the reenactments did not show a lot of first responders in action.
“More than first responders, you saw neighbors,” he said. “And one of the things we try to focus on – at least in the city of Los Angeles – is that in addition to retrofit work, we need preparedness programs.”
Gross said his department is working with other nonprofits and partners to map out communities and get neighbors connected with each other.
“It’s all about getting to know your neighbors,” he explained, “and being able to identify who’s a nurse? Who’s got an elderly relative? Who’s got pets? Who has a generator? Who’s got a chainsaw?
“That’s really important,” Gross said, “Because it’s really your neighbors that are going to save your life. They’re the ones who are going to hear you and know about you and know where to look for you.”
Beyond that personal act to protect yourself, your family and neighbors by getting to know each other, are the more tangible tasks to be done – such as retrofits, which begin by identifying the structures most vulnerable in a community.
As a former city manager, Robinson said larger cities should work with smaller jurisdictions to help them build resilience in their communities. Collaboration needs to be better, particularly given the impacts that earthquakes in one city can have on neighboring municipalities.
“There’s a social equity issue here because the larger cities like Los Angeles have the staff and sometimes the money to do the type of work that needs to be done in emergency preparedness,” Robinson said. “The smaller cities don’t necessarily have the staff, they don’t have the time, they don’t have the resources, they may not have the sophistication to deal with those issues and that’s where the cross-jurisdictional collaboration comes in. and there needs to be more of that.”
Stein, who works extensively in statistical modeling and forecasting, said insurers are getting savvy to the fact that they won’t be able to afford to cover large populations of insured customers impacted by earthquakes.
“Right now, only 15% of buildings in California are insured,” he said. “And if a significantly larger percentage were insured, the cost of insurance would become unaffordable.
“In the weird world of insurance, there is not enough money out there to cover the true losses that the state would suffer – so we have to really be ready,” he said. “We have to be strengthening our buildings, because insurance will never solve the problem.”
To view a recording of the USC Emergency Preparedness Summit 2022, visit https://www.youtube.com/watch?v=z6SP3h7ues4
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[1] Federal Emergency Management Agency, National Risk Index, https://hazards.fema.gov/nri/map
[1] USC Emergency Preparedness Summit 2022, https://www.youtube.com/watch?v=z6SP3h7ues4
[1] Los Angeles Department of Building and Housing, https://www.ladbs.org/services/core-services/plan-check-permit/plan-check-permit-special-assistance/mandatory-retrofit-programs/soft-story-retrofit-program
[1] U.S. Geological Survey, https://www.usgs.gov/programs/earthquake-hazards/earthquake-facts-earthquake-fantasy
[1] City of Los Angeles, Resilient Los Angeles, https://resilientcitiesnetwork.org/downloadable_resources/Network/Los-Angeles-Resilience-Strategy-English.pdf
[1] Southern California Earthquake Center, Third Uniform Earthquake Rupture Forecast, https://www.scec.org/ucerf
[1] Southern California Earthquake Center, Earthquake Heroes, QuakeHeroes.org
