Shortly after the Palisades and Eaton fires broke out in Los Angeles Jan. 7, 2025, engineers from the UCLA Samueli School of Engineering mobilized across burn zones to support recovery efforts and implement immediate mitigation strategies, including field reconnaissance, soil and water testing and infrastructure mapping. Some of those initial efforts have expanded into work focused on understanding the fires' lasting effects and improving preparedness and response to future disasters.
The following is an update on some of these efforts:
Soil Testing
Civil and environmental engineering associate professor Sanjay Mohanty has been testing soils through the Community Action Project Los Angeles, or CAP.LA. As of late December, his students and collaborators had collected and tested samples from more than 1,000 Los Angeles residential properties impacted by the fires, analyzing them for toxic metals including lead, arsenic and hexavalent chromium.
Early results show elevated lead levels — exceeding 80 milligrams per kilogram for residential soil, the highest safe level according to California's Department of Toxic Substances Control — in about 40% of homes in Altadena and other areas affected by the Eaton Fire. In the Palisades area, about 10% of residential samples exceeded recommended levels.
The team also tested soils from 35 public parks within the burn areas, as well as beach sand affected by runoff in the Palisades. Most of these samples showed low levels or concentrations near the recommended cutoff. Mohanty's work has been funded by grants from the R&S Kayne Foundation and FireAid, as well as support from UCLA.
"I am particularly grateful to be part of this effort to serve the community that I call my home," Mohanty said, acknowledging the many volunteers from UCLA and the broader community who have helped throughout the project. "We will continue to work tirelessly until we have tested most homes with the limited resources available and engage the community in the next step — how to remediate contaminated soil, if any, so that families can safely live on affected properties."
Looking ahead, Mohanty is also exploring whether relatively simple solutions, such as adding compost or mulch, may help bind metals in contaminated soil and reduce the likelihood of their uptake by plants or produce grown on affected land.
Similarly, civil and environmental engineering professor Jennifer Jay has teamed up with colleagues in the UCLA Fielding School of Public Health and local community groups to offer free soil sample testing at pop-up events. The LA Urban Soil Social Impact Collaborative is a community-university partnership funded by UCLA's Center for Community Engagement in collaboration with the nonprofit TreePeople.
One program held in October had more than 80 residents in Pasadena, with UCLA researchers testing more than 200 samples for lead and other heavy metals using portable X-ray fluorescence analyzers. In addition to soil testing, Jay is also working with Heal the Bay on coastal water testing.
Geotechnical Extreme Events Reconnaissance
Civil and environmental engineering faculty members Idil Akin, Scott Brandenberg and Jonathan Stewart led a multifaceted effort to organize field reconnaissance to capture the two fires' geotechnical impacts. Data collection began while the fires were still active, using aerial drones, and continued through field visits following containment of the deadly fires and again after spring rainstorms.
The team focused on critical lifeline infrastructure — including roads, water systems, wastewater systems and natural gas lines — as well as surrounding physical conditions. The group included experts from UCLA, USC, Caltech, the California Geological Survey and private firms, with assistance from government agencies.
The resulting report for the Geotechnical Extreme Events Reconnaissance Association, sponsored by the National Science Foundation, was published in June. The data will support long-term monitoring and inform models for post-wildfire hydrology, sediment movement and infrastructure resilience.
Hydrological Behavior Study
Following initial fieldwork, Akin's research group placed soil water retention sensors along several hillsides in the Palisades to monitor hydrologic changes over time. Over the next three to five years, the sensors will gather data on long-term soil impacts, including susceptibility to landslides or erosion.
"Our broader goal is to understand the initiation mechanisms of post-wildfire sediment movement during the recovery period after a wildfire," Akin said. "This will help us develop regional post-wildfire erosion, landslide and debris flow models."
Debris Removal Strategy
Jiaqi Ma, a professor of civil and environmental engineering who directs the Mobility Center of Excellence, assisted the U.S. Army Corps of Engineers in evaluating strategies to remove debris from affected areas. Using a digital twin of the City of Los Angeles created by his lab, Ma and his research group assessed factors to optimize removal. Army Corps leaders provided positive feedback on early recommendations for routing, staging and coordinated scheduling of heavy vehicle movements, sharing firsthand insights on how the Corps successfully executed debris removal at scale and how public agency and university collaboration can strengthen emergency response.
In November 2025, Ma's team shared technical lessons learned from the effort through a peer-reviewed paper presented at the Institute of Electrical and Electronics Engineers Intelligent Transportation Systems Conference, including debris removal strategy design and evaluation, as well as guidelines to inform future recovery efforts.
The Value of Fieldwork
While computational tools and laboratory equipment are integral to the research process, the value of fieldwork, especially in the immediate aftermath of natural disasters such as the L.A. fires, extends far beyond the data collected, said civil engineering doctoral student Julio Guerra. A member of Akin's research group, he has conducted fieldwork in the Palisades since the fires.
"Often, we believe we are safe from these events and consider them distant from everyday life; however, when they occur, it is difficult to anticipate the full range of consequences they may have on our lives, families and economies," Guerra said.
Communities affected by wildfires provide critical firsthand insights, and Guerra said engineers and scientists have the responsibility to translate this knowledge into work accessible and useful to communities and policymakers, with direct benefits for public well-being.
Looking Ahead
UCLA Samueli engineers will continue their efforts to apply field observations toward practical mitigation strategies, tools and support for both government agencies and local communities. By combining real-time interventions with longer-term monitoring, the researchers aim to reduce wildfire risk, protect infrastructure and safeguard communities, ensuring that lessons learned from the 2025 fires lead to tangible improvements in preparedness and resilience. "Wildfires are very common in our region, and I hope that our work will ultimately help minimize the cascading effects of wildfires on our community," Akin said.
Ongoing efforts led by UCLA Samueli faculty will be shared on the school's Rebuild LA page when updates are available.
