In This Issue
Summer Bridge Issue on Engineering for Disaster Resilience
July 1, 2019 Volume 49 Issue 2
The articles in this issue present examples of engineering innovation to develop resilient infrastructure.

Resilience by Design

Monday, July 1, 2019

Author: Lucile Jones andMarissa Aho

Los Angeles, the second largest city in the nation and home to the largest US port, is subject to some of the greatest risks from natural disasters. It is situated among the eight counties of Southern California where more than 150 fault segments are each capable of generating a damaging earthquake (Shaw et al. 2015) in an area with more than 23 million residents (figure 1). The economy of Los Angeles and Orange Counties has a GDP over $1 trillion (BEA 2018), and the region comprises geographically and politically defined cities and municipalities linked by interdependent economies, shared natural resources, and integrated transportation systems. A large earthquake that affects the city of Los Angeles also impacts the surrounding counties and has serious economic consequences and unforeseeable effects for the state of California and the nation.

 Figure 1


Los Angeles faces one of the greatest risks of catastrophic losses from earthquakes of any city in the world, eclipsed only by Tokyo, Jakarta, and Manila (Swiss Re 2013). A Federal Emergency Management Agency (FEMA) analysis of expected losses from future earthquakes predicts an annual average of more than $2 billion per year in the eight counties of Southern -California, with half of those losses in Los Angeles County alone (FEMA 2017; Petersen et al. 2014). Further-more, wildfires, debris flows, and floods are also major risk factors for the region.

Recently, the City of Los Angeles has moved aggressively in a new direction to understand and address risk and vulnerability and to increase resilience. It entered a technical assistance agreement with the US -Geological Survey (USGS) to use the science developed about the probable consequences of future earthquakes to create a long-term plan to improve seismic resilience.

A team of senior staff in the mayor’s office worked to apply the results of a century of research in the science and engineering of earthquakes to an analysis of the city’s vulnerabilities and assessment of the implications of possible approaches to reduce losses. From this, Mayor Eric Garcetti proposed 18 actions to increase the city’s seismic resilience—through ordinances (by the city council), executive action, and partnership activities—in a report titled Resilience by Design.[1] Implementation is directed by the mayor’s office, with the appointment of the second author (MA) as the city’s first chief resilience officer, a position originally funded through a partnership with 100 Resilient Cities,[2] pioneered by the Rockefeller Foundation and now institutionalized in the mayor’s office.

The resilience efforts of the City of Los Angeles have expanded beyond seismic objectives to address climate change, aging infrastructure, and economic insecurity–driven shocks and stresses. This successful effort required the integration of science and policy and can provide some insights for communities that want to -better connect scientific and engineering research to policies for stronger, safer, and more resilient communities.


The assessment of the severity of the earthquake risk for Los Angeles relied on a USGS report, The -ShakeOut Scenario (Jones et al. 2008), which details the consequences of a plausible magnitude 7.8 earthquake on the southern San Andreas fault, the fault most likely to produce a great earthquake in the conterminous United States (Field et al. 2013). Earthquakes on faults closer to the city will cause more intense -damage in parts of Los Angeles, but the very likely earthquake explored in the report happens over a larger area and strains -regional capabilities through the scale of the damage. The -ShakeOut model predicts effects of a modified -Mercalli intensity IX[3] over thousands of square kilometers and strong shaking lasting several tens of seconds (figure 2), causing about 1,800 deaths and $213 billion in economic losses across Southern -California (Jones et al. 2008).

 Figure 2

Earthquakes actually pose a much smaller risk to human life than many other risks in Southern -California; those 1,800 fatalities, which will occur only once every few hundred years, are fewer than the number of people who will die in traffic accidents in Los Angeles County over 7 years (LA County Department of Public Health 2011). However, the relative risk that earthquakes pose to individual and collective pocketbooks is much greater. In LA County, the expected annualized loss from all earthquakes is over $1.5 billion, representing one quarter of the total direct loss from earthquakes facing the nation (FEMA 2017). For reference, the $213 billion in losses in the ShakeOut earthquake equals the cost of physical damage in about 60 million car crashes (III 2019) or 60 years of accidents in LA County (OTS 2019).

Resilience by Design

The City of Los Angeles and US Geological Survey (USGS) created a formal partnership to provide scientific advice to the city as it created a plan to address its seismic vulnerability; as part of this partnership the first author (LMJ), a seismologist with the USGS, spent a year in the mayor’s office.


  • Recognizing that addressing every possible seismic vulnerability would be too large a task, the project focused on four primary goals:
  • Protect the lives of citizens during earthquakes.
  • Improve the capacity of the city to respond to -earthquakes.
  • Prepare the city to recover quickly after an -earthquake.
  • Protect the economy of the city and all of Southern California.

The results of the ShakeOut Scenario were used to identify the following areas that could be addressed through city policies and would have the greatest impact on those four goals:

  • pre-1980 nonductile reinforced concrete buildings,
  • pre-1980 soft-first-story buildings (i.e., those with windows, wide doors, and large open areas),
  • water system infrastructure, including impact on firefighting capability, and
  • telecommunications infrastructure.

Collaboration and Stakeholder Engagement

The creation of this plan for seismic resilience was the result of a year-long collaboration among policymakers, technical experts, and community stakeholders. The policymakers were primarily senior staff from all divisions of the mayor’s office, while the USGS brought in relevant technical experts.

To address dangers from vulnerable buildings, a mayor’s Seismic Safety Task Force was convened that included leaders of the state’s practicing and academic structural engineering community and engineers from the LA Department of Building and Safety. They evaluated which types of buildings pose the greatest risk and approaches to fix the problems, and then drafted proposed ordinances for consideration by the city council. Technical issues for the water system were addressed by a team of LA Department of Water and Power -employees with expertise in the various water system components. Telecommunication aspects were considered by representatives of four cellular providers. In addition to these three task forces, many outside experts were engaged to address particular areas of concern.

Much of the year’s work involved meeting with stakeholders in Los Angeles’s future—elected and city department officials, building owners, business leaders, real estate managers, civic leaders, and representatives of community organizations—and helping them both understand the ramifications of possible recommendations and compare expected losses with mitigation costs. Over 130 meetings were held in the 10 months from early February 2014 to the release of the report December 8, 2014. Most of the meetings involved a presentation about the science of the seismic risk and economic consequences, time for questions, discussion of possible approaches to address the risk, and solicitation of ideas for new approaches. The primary focus of the discussions was the potential for economic disruption.


The recommendations for buildings, water, and telecommunications were developed in parallel to address overlap. There is a strong interdependence of systems in a complex modern urban environment—the loss of water infrastructure would disrupt a large part of the economy, or damage to one building would reduce the value of others through blight or the cordoning off of adjacent properties. It makes no sense to spend a lot of money fixing buildings if there will be no water to allow occupancy after the earthquake. The focus was on increasing the resilience of the potentially fragile regional economy.

 Table 1

The resulting recommendations (table 1) were published in 2014 by the mayor’s office. Those that required ordinances from the city council were all passed unanimously in October 2015.

Resilient Los Angeles 2015–2018

Implementation of the recommendations in Resilience by Design began in 2015. As a former urban planner and the city’s first chief resilience officer, the second author (MA) was charged with leading the development of a comprehensive resilience strategy for the city.

Specific Implementation

In 2015 and 2016 the following five ordinances stemming from the recommendations were supported and approved by the city council and signed by Mayor Garcetti. The legislative process required strong support from the telecom industry, apartment associations, tenant organizations, and the engineering and construction community.

  • May 2015: Stronger telecommunications standards for all new cellular towers became law (Ordinance 183580). As of early 2019, dozens of new cellular towers had been constructed with an importance factor of 1.5 instead of 1.0.
  • October 2015: Mandatory retrofits for pre-1980 nonductile reinforced concrete buildings became law (Ordinance 183891). As of early 2019, more than 1,300 nonductile reinforced concrete buildings had received orders to comply from the Department of Building and Safety (LADBS) and 160 of these buildings had submitted the initial checklist to begin the process. As of March 2019, it was determined that 20 buildings had been previously retrofitted; none have yet completed a new retrofit under this program. These buildings have 25 years (until 2043) to complete the retrofits.
  • October 2015: Mandatory retrofits for pre-1980 soft-first-story buildings became law (Ordinance 183891). As of early 2019, more than 13,000 such buildings had received LADBS orders to comply. More than 7,800 of these buildings have formally begun the 3-step process to complete the retrofits, and 1,500 buildings have completed retrofitting, representing 21,000 households that are safer today.
  • February 2016: A cost-sharing agreement that had been heavily debated with tenant rights organizations and apartment owner associations became law (-Ordinance 184080). The ordinance limits the proportion of costs related to the mandatory seismic retro-fitting to allow building owners to pass through up to 50 percent of the total cost of the work required, up to $38 per month for each -tenant.
  • March 2016: A mandatory evaluation and retrofit of buildings that experienced substantial damage at -lower levels of shaking became law (Ordinance 184169). As of early 2019, the City of Los Angeles has not experienced a seismic event that has triggered any buildings to be evaluated or retrofitted.

Earthquake Early Warning

One of the Resilience by Design recommendations was to implement earthquake early warning (EEW) in Southern California. The City of Los Angeles had begun beta testing such a system in 2012, and in April 2017 Mayor Garcetti announced that earthquake early warning would be effective for Angelenos by the end of 2018.

The mayor’s office worked closely with USGS, first through a technical assistance agreement and then through two pilot agreements. The latter were for use of the signal from the new ShakeAlert system (; Given et al. 2018) to (a) develop, test, and pilot an EEW app with city employees and (b) link EEW to the public address system at LA City Hall. On October 18, 2018, during the Great ShakeOut, LA City Hall became the first public building with earthquake early warning. And, as promised, on December 31, 2018, the ShakeAlertLA EEW app was uploaded to Apple and Android stores in English and Spanish. As of May 2019, more than 470,000 cellular devices had downloaded the ShakeAlertLA app.

Beyond Earthquakes

In 2016 and 2017 the mayor’s office worked with 100 Resilient Cities and hundreds of subject matter experts to expand the city’s approach to resilience to other serious shocks and stresses. Partners included the UCLA Institute of the Environment and Sustainability, looking at urban heat islands and extreme heat risk and vulnerability; and USC Sea Grant and USGS Coastal Storm Modeling System (CoSMoS), looking at sea level rise and tsunami risk and vulnerability.

Using the momentum gained by implementation of Resilience by Design, additional recommendations were identified and in March 2018 Mayor Garcetti released Resilient Los Angeles,[4] a comprehensive citywide resilience strategy with 15 goals, 96 actions, and 25 targets for Angelenos, neighborhoods, the city, and regional partners. He also signed an executive directive requiring the leaders of all city departments and commissions to implement the recommendations and to include resilience principles both in their strategic plans and in the development of department budgets. In addition, nearly 30 departmental chief resilience officers were appointed, from LA World Airports to the LA Zoo, to coordinate the city’s multidisciplinary approach to resilience building.

Meanwhile, the implementation of Resilience by Design recommendations continued. The mayor’s office worked with Craig Davis, resilience manager for water at the LADWP, to advance many of the recommendations to fortify the water system. Postearthquake fire risk was researched and mapped, a panel was formed to partner with external subject matter experts, and a task force was formed by the LADWP, Metropolitan Water District, and Department of Water Resources (see Davis and Shamma 2019 in this issue). And within approximately 3 years, a pilot to install 2 miles of earthquake-resistant ductile iron pipes became a plan to install a citywide seismic-resilient pipe network that will ensure delivery of water to Angelenos after an earthquake.

Lessons Learned

There are important lessons learned. First, even as policy-makers and scientists worked in close collaboration, it was important to recognize their fundamentally different roles. Scientists can give policymakers a prediction of the probable consequences of their decisions. As citizens and voters, they probably have an opinion as to the appropriate policy to respond to that information, but that is not part of the science. Policy-makers are elected to determine policy. This distinction is important for two reasons. First, if scientists start making policy, politicians might be invited to start making science. Second, policymakers fight for the policies they have made, so empowering them to make more informed decisions creates more forceful advocates who actually have the power to get something done.

Second, it was important in bringing science and engineering to the decision makers to stay focused on what is known rather than on the uncertainties. Scientists and engineers know that uncertainties matter and are integral to the scientific endeavor. Policy-makers need answers and rely on hearing a consensus from scientists. Results are most effective when (a) it can be demonstrated that they are the consensus of the scientific and engineering community and (b) they are presented as such, not the process by which they were achieved.

Third, people support something they help to create, so engaging stakeholders in the discussion from the beginning is a condition for success. Much of the year was spent in meetings, talking about the science but also listening for ideas. Many of the details of the recommendations came from people who will be affected by the plan and could have become significant barriers to its enactment. Being able to affect some part of the plan gave them a stake in its success.

Fourth, relationships matter. The city of Los Angeles did not suddenly decide to listen to scientists and engineers. This collaboration is the culmination of decades of interactions, especially those that developed during the ShakeOut Scenario process. For the past 7 years, many scientists have been engaged in close collaboration with emergency managers, utility engineers, and regional officials. With the now annual ShakeOut drill, the message about earthquakes is being heard on a more regular basis, and it is connected to the credibility of scientific analysis as well as the relationship with the scientists and engineers. People listen to those they trust, and that trust comes from familiarity and shared experience.

Fifth, Resilience by Design intentionally set a limit, in both time and scope, to help prioritize the most critical challenges. Discussion of risks and vulnerabilities can sometimes be overwhelming to policymakers who may focus on day-to-day challenges. We intentionally did not address all earthquake problems, and we prioritized solutions that helped address other problems as well. For instance, we found that one of the most compelling ways to discuss the importance of soft-story retrofits was to remind officials that approximately half a million Angelenos were living in these vulnerable buildings. At a time when addressing the crisis in affordable housing and homelessness is a high priority in Los Angeles, reducing the risk of losing these buildings in an earthquake has multiple benefits.

Looking Forward

One of the biggest difficulties in building a resilient community is that success is defined by what does not happen, a phenomenon that to some extent must be considered impossible to measure. It is difficult for nonspecialists to understand that the lack of damage is because of their actions and not just because this earthquake wasn’t that bad. Success is also a form of delayed gratification; the consequences may be seen only decades after the action taken. The long delays and somewhat hidden results (a successful retrofit should not look different) make building social momentum a challenge.

It is thus particularly gratifying that the current effort by Los Angeles seems to be playing out in ripple effects across the region. Since Los Angeles passed the retrofit ordinance in October 2015, similar ordinances have been passed in five other Southern California cities and are under consideration in several more. Both authors continued engaging with other regional cities after the release of Resilience by Design to support further action. Two cities (Santa Monica and West Hollywood) went beyond Los Angeles and included mandatory retrofit of pre-1994 welded steel moment-frame buildings.

All of these programs have been adopted without the occurrence of a significant local earthquake. It will be interesting to see how many more communities might join the effort after the next damaging earthquake. One might expect that the increase in action may depend on the degree to which the retrofitting ordinances will appear to have been successful.


The collaboration described in this paper was the work of an untold number of people at all levels in Southern California, made possible by the leadership of Mayor Eric Garcetti. Describing the work is an endeavor made easier by the great editing of Cameron Fletcher.


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[3]  The Mercalli scale (I–XII) measures the effects of an earthquake quantified from observations of effects on buildings, people, objects, and the Earth’s surface, while the Richter scale (2.0–10.0) uses a seismograph to measure the energy released by an earthquake. 


About the Author:Lucile Jones is founder and chief scientist of the Dr. Lucy Jones Center for Science and Society and a visiting associate in geophysics at the Seismological Laboratory, California Institute of Technology. Marissa Aho was the first chief resilience officer in the Office of the Mayor of Los Angeles and is now chief resilience officer in the Office of the Mayor of Houston.