Los Angeles Mayor Eric Garcetti was joined by Optimum Seismic Co-Founder Ali Sahabi at a press conference celebrating the city’s 7,000th earthquake retrofit — a big step in the city’s ongoing push for greater earthquake resilience. The event was held in conjunction with the Great Shakeout in October
LOS ANGELES – Mayor Eric Garcetti and I met recently at an apartment building earthquake retrofitted by Optimum Seismic to celebrate two major milestones the City of Los Angeles has passed on the road to becoming more earthquake resilient.
Mayor Garcetti signed into law a historic mandatory building retrofit ordinance in 2015 to ensure L.A.’s most vulnerable buildings are strengthened to prevent loss of life in the event of a major earthquake.
Now, some 7,000 buildings have been fully earthquake retrofitted in Los Angeles – an incredible feat, driven by the retrofit law he guided through the City Council in 2015.
In addition, of the 12,558 soft-story buildings and 1,222 non-ductile buildings identified by the City as requiring mandatory retrofits, some 93% of these buildings have completed plans to retrofit as of September 2021, and are on their way to meet requirements within the 7-year timeline for full compliance.
The ordinance requires mandatory seismic retrofitting for soft first-story buildings, built before 1980. Soft first-story buildings, which are often apartments, are wood frame buildings that have a large opening on the first floor for things like tuck-under parking and garage doors. In retail buildings they may include large display windows.
The ordinance also covers buildings made of non-ductile reinforced concrete.
“As Californians, it’s critical that we know what to do and take steps to be prepared before, not after, an earthquake strikes,” Mayor Garcetti said at the joint press conference with Optimum Seismic. “Here in Los Angeles, we’ve made resilience a priority, retrofitting our most vulnerable buildings to protect Angelenos’ lives and property.”[i]
Optimum Seismic has been a longtime advocate for earthquake safety, having worked closely with Mayor Garcetti, other government leaders and business and industry representatives to enact programs that help business owners fortify their buildings so they’re still standing after a major seismic event.
The exact benefits of those 7,000 retrofits are real, but are hard to quantify at this time. Still, there is no doubt these retrofits will save lives and spare communities from the economic devastation those buildings would have caused – had they collapsed.
“You can’t count the living. You can only count those that are lost,” Garcetti said. “Today, we know that this work will result in people who will still be here after the next Big One, and that is worth doing.”
I applaud the mayor’s foresight and leadership. He has done much to build on the resilience of L.A., in many different ways.
Step-by-step progress
Improved engineering and design standards for new construction, and the protection of public buildings and infrastructure have made our cities safer than they have been in the past.
The Los Angeles Department of Water and Power has been busy replacing its 7,000 miles of pipeline with more resilient material – focusing on services to public facilities such as hospitals, command centers, and shelters.[ii] It is constructing the new Headworks reservoir to directly serve communities that may be cut off from other water supplies after an earthquake.[iii]
Throughout the state, structures continue to be retrofitted, with several cities and counties requiring seismic fortifications to buildings known to be vulnerable to damage in a major earthquake.
Los Angeles has consistently been on the forefront of that resiliency movement.
But on a broader scale, there is still much to do to attain the level of resilience needed to avert disaster.
Unprecedented Damage Still Possible
Will Los Angeles still be functional once the ferocious earthquake occurs that many experts insist is long overdue?
When it happens, it is estimated one in every 16 buildings in the city will be damaged, forcing more than 3.5 million people out of their homes. [iv]
Water lines will be broken, cutting off service to some areas for up to six months.[v]
Gas lines will burst, and power lines collapse, sparking massive fires some say could burn to the ocean.[vi] (The San Francisco quake of 1906 broke water lines and resulted in a massive conflagration that leveled 22,400 buildings. Even in the 1994 Northridge quake, which was relatively small, 110 fires contributed to the severe damage of 12,000 buildings.)[vii]
And now, the Los Angeles Times reports a U.S. Geological Survey analysis finds that widespread disruption of cell phone service will “imperil the public’s access to 9-1-1 and lead to delays in reporting fires and calling for medical help.”[viii]
Some people lucky enough to not be directly affected by damage or service disruptions may find themselves suddenly unemployed as businesses close shop from damage to their buildings.
“Models of a big earthquake on the southern San Andreas fault estimate that as many as 10% of the high-rises designed to the current code in downtown Los Angeles will be so compromised they will have to be torn down after the earthquake. Our physical lives will have been spared, but our economic lives could well be in tatters,” seismologist Lucy Jones wrote in a recent Op-Ed.[ix]
And remember, there are many smaller faults much closer to Los Angeles than the San Andreas. Those lesser known faults, which crisscross the area, can be expected to produce smaller quakes, but create greater impact due their proximity to densely developed areas.
Other estimates say at least five pre-1994 steel moment-frame high-rise buildings would collapse, with about 5,000 people inside them if the quake strikes during regular business hours. And as many as 50 low- and mid-rise concrete moment-frame buildings would collapse, and 900 unreinforced masonry buildings would be irreparably damaged.[x]
This chaos is hard to imagine — millions of people displaced, essential services cut off, limited communications when needed most, fiercely burning fires and crippled water services unable to douse the flames – and the dramatic economic collapse of the city and region as businesses close and high unemployment lingers for decades to come.
Many would try to stay in LA. Other wouldn’t. Homes and other properties that survive the damage might have their values depressed, and be difficult to sell your property. Moving from the area may become much more difficult if the pool of buyers shrinks suddenly as jobs are lost.
An uncomfortable reality
None of us likes hearing that life as we know it is in jeopardy. But we need to face these realities to adequately assess and address these risks.
“You’re asking people to think about things that they don’t like to think about – especially when you’re asking them to think about their property, which is usually their largest financial asset,” said Patrick Otellini, once the nation’s first chief resilience officer, serving the City and County of San Francisco. He was largely credited with building public support for San Francisco’s 2013 soft-story retrofit law – the first of a growing number on the books. “Getting the public behind this and getting consensus around the thought of seismic safety is huge.”[xi]
Laurel Rosen, director of the Santa Monica Chamber of Commerce, said cities and community leaders need to work hand-in-hand to informing the public about risks not only to buildings, but to the quality of life in a community.
“We have over 1,400 vulnerable buildings in the city,” she said, joining Otellini on a recent episode of The Resilience Advantage webinar series. She credited city leaders for helping to garner support to make those structures safer.
“Retrofits are very important in our community for so many reasons,” she said. “There’s so many liabilities around the aspect of vulnerable buildings that impact not only businesses but employees. It impacts the whole community.”[xii]
Maria Salinas, president and CEO of the Los Angeles Area Chamber of Commerce, agreed.
“Angelenos have always known the danger of events – from wildfires to earthquakes and everything in between,” Salinas said. “And as we emerge from the pandemic, the need for greater resiliency is evident.”
“If we are to thrive, we must prepare for the next disaster. That’s our life. Preparedness is the key to safety in our region, and it’s the key to economic resiliency,” she added.
Stanford University calculated that a 7.2-magnitude earthquake along the Hayward fault in the San Francisco area would be disastrous. “Direct [building and infrastructure] losses from simulations are U.S. $115 billion,” the report found. More than $60 billion of that would occur in the housing sector. Infrastructure damage would result in ripples through the economy causing an additional $35 billion in losses.[xiii]
The study estimates that it may take more than two years for the regional economy to recover.[xiv]
Similarly, a 6.9-magnitude earthquake along the Rose Canyon fault in San Diego would devastate the seaside city, according to the Earthquake Engineering Research Institute.
In a study EERI unveiled at the 2020 National Earthquake Conference in San Diego, the institute projected extensive losses from such a quake:[xv]
- 45% of all residential buildings damaged
- 23,000 residential units severely or completely damaged
- 36,000 households displaced
- 40% of commercial and industrial buildings damaged, (20% extensively or beyond repair)
- $38 billion in damage
- $5.2 billion in lost income
“(Earthquake) damage to buildings is expected to be severe and widespread, particularly in the heavily populated coastal areas and in the older urban areas,” the study found. “While most newer buildings, particularly single-family residences, can be expected to survive the scenario earthquake with repairable damage, many larger and older buildings can be expected to be more severely damaged and potentially unsalvageable.”[xvi]
What Can Be Done?
Only four other cities in Los Angeles County have adopted similar retrofit ordinances for soft-story buildings as has Los Angeles. None have enacted ordinances in other Southern California counties. The collapse in Florida this past summer gave many shudders, but how much worse will things be in widespread earthquake damage? Who will be responsible for deaths, injuries and property losses?
Retrofits are a proven, cost-effective method to improve earthquake resilience for existing buildings.
For new construction, the latest in engineering and design concepts, add only a 1% to 2% increase over minimum code-based design costs, but their effectiveness far exceeds those costs, according to calculations by the United States Resiliency Council.[xvii]
Some new approaches include base isolation and dampers – where the building rests on flexible bearings or pads known as base isolators, which disperse an earthquake’s energy much like a car’s shock absorbers dissipate roadway vibration. This approach has proven to be extremely effective in preventing damage in an earthquake. A retrofit of the William Clayton building in Wellington, New Zealand, with seismic dampers and isolators protected the structure during the 2016 quake – making the building a refuge for workers displaced from other buildings at the time.[xviii]
Methods such as these help a structure to withstand the pressures, vibrations, and lateral expansion forces that put a building under stress during an earthquake.[xix]
Other techniques used, depending on the structural design and composition of the building, include:
- The installation of external post-tensioning to help keep a building centered
- Reinforcement of concrete columns and connections within buildings
- Reinforcement of masonry to prevent it from falling loose
[i] PRNewswire, Mayor Garcetti and Optimum Seismic highlight earthquake retrofits making 7,000 Los Angeles apartment buildings safer from quakes, https://www.prnewswire.com/news-releases/mayor-garcetti-and-optimum-seismic-inc-highlight-earthquake-retrofits-for-making-7-000-los-angeles-apartment-buildings-safer-from-quakes-301406459.html
[ii] ABC Channel 7, https://abc7.com/earthquake-la-dwp-utilities-water/8426107/
[iii] KCRW, https://www.kcrw.com/news/shows/greater-la/in-altadena-the-sierra-madre-fault-rises-to-the-surface/you-may-survive-the-big-one-but-las-water-supply-may-not
[iv] U.S. Geological Survey, The Great ShakeOut, https://pubs.usgs.gov/of/2008/1150/
[v] KCRW, https://www.kcrw.com/news/shows/greater-la/in-altadena-the-sierra-madre-fault-rises-to-the-surface/you-may-survive-the-big-one-but-las-water-supply-may-not
[vi] LAist, “If it’s a windy day when a big quake hits, L.A. could burn to the ocean,” https://laist.com/news/if-its-a-windy-day-when-a-big-quake-hits-la-could-burn-to-the-ocean
[vii] LAist, “If it’s a windy day when a big quake hits, L.A. could burn to the ocean,” https://laist.com/news/if-its-a-windy-day-when-a-big-quake-hits-la-could-burn-to-the-ocean
[viii] Los Angeles Times, “California earthquake could cut off communications for weeks,” https://www.latimes.com/california/story/2021-10-21/california-earthquake-could-cut-off-communications-for-weeks
[ix] Dr. Lucy Jones, Los Angeles Times, https://www.latimes.com/opinion/story/2021-08-25/earthquake-building-codes-functional-recovery-life-safety
[x] Ibid.
[xi] Patrick Otellini, The Resilience Advantage, https://www.optimumseismic.com/the-resilience-advantage/
[xii] Maria Salinas, The Resilience Advantage, https://www.optimumseismic.com/the-resilience-advantage/
[xiii] “Quantification of Disaster Impacts through household well-being losses,” Nature Sustainability, www.nature.com/natsustain
[xiv] Stanford University Urban Resilience Initiative, http://urbanresilience.stanford.edu/
[xv] Engineering and Environmental Research Institute, https://sandiego.eeri.org/2014-eq-scenario/
[xvi] Ibid
[xvii] United States Resiliency Council, “The Resilience Advantage,” www.usrc.org
[xviii] Science Learning, https://www.sciencelearn.org.nz/resources/331-seismic-engineering#:~:text=Seismic%20engineering%20is%20a%20branch,bridges%2C%20resistant%20to%20earthquake%20damage.
[xix] International Geophysics https://www.sciencedirect.com/topics/earth-and-planetary-sciences/seismic-engineering
