Nicholas Depsky (left) and Seigi Karasaki stand near the Harbor Channel in Richmond, California, where numerous industrial facilities may be impacted by sea-level rise.

Toxic Tides

Over three feet of sea-level rise is expected by the end of the century if little is done to slow climate change. Much of the conversation in the United States around sea-level rise has focused on wealthy areas like Malibu and threats to expensive properties. The Toxic Tides project, launched in 2019, reframes the issue by focusing on far less photogenic—and far more prevalent—stretches of coastline that are home to hazardous sites like industrial facilities, oil and gas wells, landfills, and sewage treatment plants. These sites are often located near poor communities and communities of color that already suffer from environmental injustices.

“Climate change is here,” says Rachel Morello-Frosch, a professor in the Department of Environmental Science, Policy, and Management and the School of Public Health who co-leads the project. “We have wildfires, tornados, floods. Sea-level rise is a much slower-moving storm.” The Toxic Tides project calls attention to that slow-moving storm, offering crucial information about the future as well as the opportunity to do something about it. And, Morello-Frosch points out, the project aims to ensure environmental equity is prioritized in the process. “This key component is often missing in the conversation around sea-level rise, but should be central to climate-action planning at every level,” she says.

Knowing she’d need a multidisciplinary team to map the effects of sea-level rise along the entirety of California’s coast, Morello-Frosch recruited graduate student researchers with experiences ranging from community engagement to R programming and Geographic Information Systems (GIS). The team has now released a free online tool showing that flooding in coming decades will threaten over 400 hazardous facilities along the state’s coast and will disproportionately impact disadvantaged communities living near them.

Collaboration is Key

Two of the students crucial to the success of the program are Nicholas Depsky and Seigi Karasaki, both PhD students in the Energy and Resources Group (ERG). In addition to technical skills, they’ve drawn from their experiences outside the academic realm—from the worlds of music, rock climbing, and TEDx—in their approach to not only the data itself but also to whom this crucial information reflects and reaches.

Collaboration has been encoded in the Toxic Tides project’s DNA since the start. Leading the research with Morello-Frosch is Lara Cushing (BS ’03 Molecular Environmental Biology, MPH ’11 Epidemiology, PhD ’15 ERG), a three-time Cal alumna who is now an assistant professor of environmental health sciences at UCLA’s Fielding School of Public Health. The pair sourced sea-level-rise data from Climate Central, an independent organization of leading scientists and journalists researching and reporting the facts about the changing climate and its impact on the public.

"There is a lot of power when we unite and leverage research and data to support policy advocacy and change."
Amee Raval

Five community advocacy organizations from throughout California are collaborators on the Toxic Tides project and serve on the project’s advisory committee. They’ve provided guidance and feedback on everything from overall study design and metrics to information dissemination, to ensure the project accounts for the lived experiences of those in vulnerable fence-line communities.

“This was not just checking the box on community engagement,” says partner Amee Raval, MS ’16 Environmental Health Sciences. She is policy & research director at Asian Pacific Environmental Network (APEN), which advocates for environmental, social, and economic justice for Asian immigrant and refugee communities in the Bay Area. “There is a lot of power when we unite and leverage research and data to support policy advocacy and change.”

The research team in Morello-Frosch’s Sustainability and Health Equity (S/HE) Lab itself has included members from across multiple UC Berkeley departments. “That’s one of the great things that our College cultivates: the importance of collaboration in order to solve challenging problems,” Morello-Frosch says. Jessie Jaeger, MCP-MPH ’20, who has since graduated with master’s degrees in city and regional planning and public health, initiated the “cleaning” of facility location and census data. Yang Ju, PhD ’19, came from the landscape architecture and environmental planning program; he was the primary architect of the Toxic Tides online mapping tool.

Karasaki was highly motivated by the opportunity to work on a community science collaboration in his home state after studying in Japan and conducting research in China as a Fulbright scholar. Depsky wanted to use his technical modeling skills to influence climate-change policy.

“All of the students involved have different training and disciplinary orientations,” says Morello-Frosch. “But the thread that ties everyone together is the deep interest in having environmental justice as an underlying motivator of the research questions they pursue.”

Improvisation in the Key of D (for Data)

When Depsky needs to unwind, he picks up his guitar or plays his piano. His true passion is jazz; improvisation comes naturally to him. “I noodle and create ideas of my own that I mess around with,” he says.

Depsky’s talent for riffing applies equally to spatial analysis—a process of examining geographical data (such as latitude, longitude, and elevation), extracting or creating new insights through computer modeling, and then exploring those insights. “He is always ahead of the ball, trying to think about other ways to do a data mash-up that will help solve a problem,” Morello-Frosch says.

For example, the team faced significant difficulties in pinpointing the exact location of coastal hazardous facilities. Their key data source—the U.S. Environmental Protection Agency’s Facility Registry Service—proved to be inaccurate for many facilities.

“Location was a crucial component that we needed to get as right as we possibly could to determine if the facility was within a floodplain and at risk of sea-level rise and flooding in future years,” Depsky says.

The team incorporated tax parcel records and used Google’s Application Programming Interface (API) tools to update the geographical coordinates of sites, significantly improving the location accuracy of the data.

Likewise, census information was not detailed enough to pinpoint where populations lived within larger rural census tracts and block groups. Depsky developed a novel mapping method that utilized Microsoft Building Footprint data and tax parcel data to give the researchers a much more precise picture of where people lived in relation to hazardous sites.

Back to the Drawing Board

Oxnard resident Lilian Bello stands alongside the Mandalay Generating Station, a gas-fired power plant on the coast in Oxnard, California

Oxnard resident Lilian Bello stands alongside the Mandalay Generating Station, a gas-fired power plant on the coast in Oxnard, California—one of many facilities that will be affected by sea-level rise in the area. Bello and other local residents have organized for years to remove toxic and polluting facilities from their coast. Photo by Chris Jordan-Bloch for Earthjustice.

Where Depsky unwinds with music, Karasaki heads to the great outdoors for backpacking, hiking, and especially rock climbing. His crowning achievement—so far—came in May 2018, when he and his climbing partner Peter Marsters, MA ’15 ERG, reached the nearly 3,000-foot summit of Yosemite’s El Capitan via The Nose, a technical climbing route that took them three-and-a-half days to complete.

“It wasn’t our first time; we’d tried it before and realized we were moving way too slow or weren’t prepared in the ways we thought we were,” he says. “There was a lot of going back to the drawing board.”

The iterative feedback process between the Toxic Tides academic researchers and the community advisory committee guaranteed a lot of trips back to the drawing board for Karasaki and his fellow team members. Over the course of three years, community partners periodically joined the research team’s weekly meetings to provide input. And at annual workshops through Zoom, they gave specific feedback about prototype maps. Karasaki was in his element as he staffed the Zoom breakout rooms in which these discussions unfolded. “It was great to get a mixed coalition of people coming together and really thinking about the platform’s strengths and weaknesses,” Karasaki says.

Community partners suggested hazardous sites not in the EPA database and helped refine how sites were categorized. They also identified which social vulnerability indicators best reflect the lived experiences of the disadvantaged communities surrounding the hazardous sites. As a result, the Toxic Tides map is searchable not only by unemployment rate, education level, and diversity but also by rental rates, voter turnout, and language isolation—households with limited English-language skills.

View Toxic Tides maps and data on the project website.

Translating Science for the Public

Before unveiling the mapping tool through statewide and then regional events at the end of last year, the Toxic Tides team spent a lot of time discussing how to ensure that their tool is accessible to those living in communities affected by sea-level rise, as well as advocates and legislators. “Who this information reaches is as important to me as the research itself,” Karasaki says.

Translating scientific data into everyday language is a challenge that Karasaki knows well. While working on a master’s degree in international environmental studies at the University of Tokyo, Karasaki organized the TEDxTodai conference. “The real challenge is not only for the speakers to pitch an idea in 18 minutes or less, but to pitch it in a way that anyone without any prior scientific background can understand and find relevant to their lives,” he says. “It’s a problem across all disciplines of research. I wish more people would think about how, after their research gets published, it then reaches the public.”

Clarity of the Toxic Tides information was a top priority for Karasaki. “On the data side, I made sure that the data actually represented what we said they did,” he says. “But then I kneaded that data into more intuitive and easily digestible formats—graphs, visualizations, explanations—for people outside the project.”
Toxic Tides has made a significant impression across the state. “It’s a really powerful project,” says Raval. “The findings are compelling. They reinforce and add a sense of urgency to what many of us in the communities already know.”

Looking ahead, the Toxic Tides team is setting its sights beyond the borders of the Golden State. “Our goal is to integrate the work we’ve done in California and scale it up nationally through Climate Central’s Surging Seas interface,” Morello-Frosch says, adding that the team also plans to translate the tool into Spanish. “We want to continue improving this tool, making it more nimble and able to provide even more information and flexibility to look at different kinds of scenarios.”

Depsky and Karasaki are on board as this next chapter unfolds. “Seeing the positive response and the striking results definitely puts wind in the sails,” Depsky says. “It will be exciting to see how this scales up nationally.”