The Brief

Researchers out of UC Irvine have said that nationally used flood modeling lacks specificity when it comes to measuring risks in urban areas like Los Angeles County.

They've created their own modeling system, PRIMo-Drain, that can better predict which properties are at risk when using accurate, granular data.

How the flood modeling system works

In a new report, UCI engineering professor Brett Sanders and his team compared widely used national flood risk assessment modeling in areas like Los Angeles County against their own PRIMo-Drain model. Long story short: Traditional models don’t usually include infrastructure like levees and dams, unresolved drainage and topographic data, which means their modeling is less specific when it comes to measuring risks for the spreading of floods in cities.

That data on storm drain infrastructures is collected mostly from GIS (geographic information system) shape files maintained by public agencies like the Los Angeles Department of Public Works. The UCI researchers also updated those databases with aerial image capture of the conditions of levees mapped in public records.

“Once we have this relatively detailed representation of the land surface, of the flood infrastructure, we look at different types of flooding,” Sanders said.

Those types of flooding include river floods, coastal floods, and flash floods from intense rainfall, like what Los Angeles saw the past two winters. Estimates show the frequency of extreme rainfall under a warmer atmosphere to likely be higher in seasons to come.

In recent years, large rainfall events in Southern California have been kept at bay by flood control infrastructure like those aforementioned levees and dams (the technical word for them is mainstem). But water is starting to reach above levee and dam walls more often. Places like Santa Barbara and San Diego experienced these flooding scenarios in the latest few rounds of atmospheric rivers.

This is why PRIMo-Drain researchers want to get as specific as possible in future models. If they could measure where water goes after escaping flood control walls and what areas get flooded, even more accurate models could be put to use for cities.

According to Sanders, part of this is why the developers of the model engage in “collaborative flood modeling” with the Los Angeles Regional Collaborative for Climate Action and Sustainability out of UCLA. The idea is to ask people where they see flooding, what they think drives flooding, and for suggestions on data sources that could help improve the model.

The model became publicly available in 2023. Since then, organizations like the City of Los Angeles and Southern California Edison have used PRIMo for planning and vulnerability measurement purposes.

Strategies to maintain flood risk

Right now Sanders and researchers on the PRIMo team are engaged in a two year study in Los Angeles in partnership with Los Angeles County and community groups to look at alternative strategies to manage this risk to communities and who they would benefit. (The same team also conducted a 2022 study that found L.A. County’s Black residents face disproportionately high flood risks.)

There are three strategies they’ve identified as potential solutions. The first is a tried and true method: make levees taller so that channels have more capacity and can prevent water from escaping the levee walls.

Another strategy involves widening channels to create more capacity, which would eliminate some of the concrete in channels and allow for vegetation to begin growing.

Sanders said the third strategy would be to “capture more storm water in the upper parts of the watershed…with more parks, more green space, and more infrastructure that would promote the infiltration of rainwater into the soil.” Ideally, this would reduce the amount of water that flows down these channels and in doing so reduce the risk facing these lowland cities.

In the meantime, the researchers will continue working on updating their models during future rain events. According to Sanders, it’s still “really hard to say [the researchers’] method is more accurate” since it hasn’t been exposed to enough severe flooding.

The Trump administration is suing California over a law preventing new oil and gas wells from being located too close to schools, homes and other sensitive sites. The 2022 law, Senate Bill 1137, prevents new drilling within a safety zone of 3,200 feet, a little over half a mile, around schools, hospitals and parks, based on public health recommendations.

In the suit filed in January in the U.S. District Court for the Eastern District of California, the U.S. Department of Justice said SB 1137 violates federal law and hampers domestic energy development. “SB 1137 would knock out about one-third of all federally authorized oil and gas leases in California,” said the Department of Justice in a press release. The government’s request for a preliminary injunction stopping the enforcement of SB 1137 is scheduled to be heard on March 20.

SB 1137 went into effect in 2024 after a long battle between environmental health groups and the oil industry. The 3,200-foot buffer was created to reduce exposure to harmful toxins. However, there are already many oil and gas wells within the safety zone protecting schools, and the law allows those wells to continue operating as long as they comply with additional regulations. Those new requirements include closely monitoring emissions, reporting leaks and accidents and limiting dust, noise and light emanating from the facility.

Health and safety risks with exposure to oil wells

As many Californians know, oil extraction has a long history in the state. With urban sprawl, neighborhoods and schools ended up near wells. The close proximity of children to the wells can have deadly impacts, claim environmental justice advocates, due to highly toxic chemical byproducts of oil extraction, including benzene and hydrogen sulfide. Communities close to oil and gas wells, studies have suggested, are at increased risk for asthma, cancer, cardiovascular disorders and negative birth outcomes.

In addition to long-term health impacts, there are immediate safety issues involving oil production sites, with several noted accidents in the past year: an explosion and fire at a refinery in El Segundo and oil spills in Ventura and Monterey counties.

A history of oil wells near homes and schools

Unlike other oil-producing states, California drilling often happens close to homes and directly in neighborhoods. A 2020 analysis found that over 2 million people in the state live within a half-mile of an oil or gas well. About 7.37 million Californians live within 1 mile of a well — nearly one-fifth of the state’s population — with low-income communities and communities of color disproportionately exposed.

Oil and gas wells are concentrated in Southern California, where they appear in often surprising places — like the oil derrick (now decommissioned) once located at Beverly Hills High School. Many schools are even closer than the 3,200-foot setback mandated by SB 1137 for new drilling, with 175 schools within 1,500 feet (a more conservative safety zone used by the Dallas City Council in a 2013 ruling) of an oil or gas well.

A concentration of schools near oil wells in the Los Angeles basin

EdSource’s analysis showed the greatest numbers of schools located in the state’s safety zone are within the Los Angeles basin, including the city of Los Angeles and the nearby cities of Long Beach, Compton, Torrance, Whittier, Montebello and Huntington Beach. In the Los Angeles Unified School District, 165 schools are within 3,200 feet of an oil or gas well, nearly 13% of LAUSD schools. In Long Beach, 23% of schools are in the SB 1137 safety zone — 22 of a total of 94 schools.

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Justin Allen

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EdSource

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EdSource

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EdSource Data Journalist Daniel J. Willis contributed to this report.

This story was originally published by CalMatters. Sign up for their newsletters.

With the Trump administration escalating immigration enforcement, a number of California municipal and county governments are setting aside public money to help immigrants and rapid response networks build legal defenses.

San Francisco and Alameda County are among the latest to designate additional money for immigrants to defend themselves against deportation. In October, when President Donald Trump threatened to increase Immigration and Customs Enforcement in the Bay Area, the San Francisco Board of Supervisors beefed up its defense fund by a unanimous vote with $3.5 million. In March, Alameda County doubled the fund it had started with $3.5 million.

Richmond, Los Angeles and Santa Clara County also have established immigration defense funds. And Bay Area cities have joined forces to create Stand Together Bay Area Fund, a legal resource completely funded by philanthropy.

Santa Clara County Supervisor Susan Ellenberg said it’s in the county’s best interest to protect immigrants, who make up 40% of its population.

“ We have a direct nexus and concern to people who are working, living, raising families, paying taxes, participating in our community and keeping our economy and our social fabric strong,” Ellenberg said. “ So our local dollars are being spent to protect local interests.”

Caitlin Patler, associate professor at the University of California, Berkeley, Goldman School of Public Policy, said the funds are necessary, given the large immigrant population in the United States and the punitive nature of immigration courts.

“I don't think that anyone should be representing themselves in any courtroom when the government comes with an attorney every time,” she said.

Unlike criminal cases, deportation proceedings are in civil court, which means those defending themselves against the federal government do not have a right to a court-appointed lawyer free of charge. But the cases have an enormous impact on people’s lives.

“Immigration judges have said these cases are like adjudicating life sentences in a traffic court setting,” Patler said.

Legal funds precede Trump's election

Local government investments in defense funds for immigrants are not new, and they precede the Trump era.

In 2013, New York City became the first major city to implement a pilot legal defense fund for immigrants, after the Obama administration ramped up enforcement. San Francisco launched a similar program the following year.

A 2014 study by the Northern California Collaborative for Immigrant Justice found that immigrants represented by a lawyer from a number of Bay Area nonprofits won 83% of their removal hearings, substantially higher than those who had no representation. But two-thirds of detained immigrants didn’t have any access to legal counsel.

California established an Immigrant Assistance Program in 2015, shortly after the Obama administration expanded the Deferred Action for Childhood Arrivals program, enabling more immigrants who came to the U.S. undocumented as children to legally live and work. Known as “One California,” the $45 million fund supports nonprofits that serve immigrants including with legal help. The program prohibits funds to be used for those convicted of a serious felony.

The fund is part of the annual budget year after year, although debates have emerged on whether the funds can be used by immigrants with felony convictions. Last year, Gov. Gavin Newsom signed a budget bill that some immigrant advocates criticized as too restrictive because it appeared to expand the number of felony offenses that exclude someone from state-supported legal support. Newsom’s stance aligned with Republicans who wanted to tighten access to the fund. 

While immigrant defense funds started more than a decade ago, the trend picked up in late 2016, after Trump’s first election. That year, Trump campaigned on toughening border enforcement and discouraging immigration throughout the country.

Los Angeles soon after Trump’s inauguration in 2017 became one of the cities to set up funds for immigrants to use against deportation.

It was the start of a $10 million public-private fund launched by former Los Angeles Mayor Eric Garcetti. The Los Angeles Justice Fund, which was expanded in 2022 to create RepresentLA, is an ongoing investment by the city, county and philanthropic organizations.

More funding after Trump's re-election

A month before Trump’s second presidency, Santa Clara County allocated $5 million to support response activities related to Trump’s targeting of immigrants. Since then, it has increased that allocation to $13 million.

Santa Clara’s fund is more expansive than most others, Ellenberg said, supporting an array of immigration resource organizations including the Rapid Response Network, as well as legal defense, outreach, education and prevention efforts.

Demonstrators chant during a protest against recent federal immigration enforcement efforts, outside Super Bowl LX at Levi’s Stadium in Santa Clara on Feb. 8, 2026.

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In September, San Francisco Mayor Daniel Lurie stood at a news conference with the mayors of Oakland and San Jose to announce the Stand Together Bay Area Fund, with a goal of raising $10 million to support immigrant families impacted by detentions and deportations. The cities have not allocated any public dollars to this fund, which is being managed by the nonprofit San Francisco Foundation.

“ My understanding is that their role is to support fundraising,” said Rachel Benditt, the foundation’s spokesperson. “I do not believe that they will be donating money from the city budgets.”

In a news release about the fund, Oakland Mayor Barbara Lee said it will pool resources from individuals, corporations, the faith community, and philanthropic partners to support nonprofit groups working with immigrant communities.

Three Alameda County supervisors are using some taxpayer money to support the effort. It will come from the so-called discretionary budgets they receive to support activities in their districts. Supervisor Nikki Fortnato Bas said she will donate $50,000 to the cause.

“These dollars are one piece of a much larger fight,” she said in a news release. “A fight for dignity, for rights, and for the future of our democracy.”

This story is part of “The Stakes,” a UC Berkeley Journalism project on executive orders and actions affecting Californians and their communities.

The California Democratic Party is betting that a tried-and-true playbook and standard-bearer candidates offer their best chance to take back the U.S. House in November’s midterms rather than fresh faces and more populist policy planks.

The country’s largest state Democratic party endorsed a slate of aging congressional incumbents at its convention in San Francisco after a weekend that illustrated the high stakes in this year’s midterms. In congressional districts without an incumbent, the party gave the nod to a handful of current state lawmakers who, while younger, are party insiders compared to the grassroots political outsiders who are running as Democrats in contested races.

Among the incumbents who sailed to endorsements were Rep. Mike Thompson of St. Helena, 74, who’s running for his 15th term, and Rep. Brad Sherman of the San Fernando Valley, 71, seeking a 16th term.

In the open race to succeed the late Republican Rep. Doug LaMalfa, who represented the state’s rural north for more than 13 years, state Sen. Mike McGuire overwhelmingly won the party’s endorsement despite an internal spat with party leadership that almost forced a vote of the entire convention floor.

At right, actor Sean Penn watches U.S. Rep. Eric Swalwell, candidate for California governor, speak during the afternoon general session at the California Democratic Party convention in San Francisco on Feb. 21, 2026.

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The outcome, while not surprising, disappointed several grassroots political outsiders who sought to give their party a facelift and push beyond the anti-Trump rhetoric that its leaders have relied on since President Donald Trump was first elected in 2016.

“This weekend just reaffirmed why we need to push the Democratic Party for new leadership. It also reaffirmed to me why people are leaving the Democratic Party,” said Mai Vang, a progressive Sacramento city councilmember.

Vang is the first elected official to challenge Rep. Doris Matsui in the 20 years since she took over her late husband’s Sacramento-area seat in the 7th Congressional District. Matsui, 81, ultimately won the endorsement despite a challenge from Vang. She argued the endorsement caucus had unfairly allowed Speaker Emerita Nancy Pelosi, who was not a delegate for the 7th District, to give a speech in support of Matsui, a 10-term incumbent.

Jake Levine, a former Biden White House aide who’s running against Sherman, argued that Democrats can’t keep beating the same anti-GOP, anti-Trump drum without also outlining a clear vision for addressing young voters’ anxieties on issues like the high cost of housing and a scarcity of good-paying jobs.

“Yes, we need to flip the House, but we also need to put a new generation of leaders in the House when we take it over,” Levine said. “In order to sustain a party that can keep winning for many more years, we need a new message. And the people who have gotten us to where we are today are still stuck in the politics of yesterday.”

The weekend also served as a swan song for Pelosi, the San Francisco political titan and first woman speaker who announced last year that she would retire after her current term. Pelosi was repeatedly lauded for cultivating generations of elected officials, including Sen. Adam Schiff. His uncharacteristically fiery and profanity-laden speech on the convention floor spoke to the pent-up anger and frustration with the Trump administration that has turned even the party’s mellower figures into all-out fighters.

Schiff bellowed from the stage that the massive turnout for Proposition 50, which redrew congressional districts to favor Democrats, sent a resounding message to the Trump administration: “When you poke the bear, the bear rips your f—ing head off!”

'We need people who know what they’re doing'

In their own defense, time-tested incumbents argue that now is not the time to bring in an entirely new class of lawmakers as House Democrats try to reign in a rogue second Trump administration.

“This is not the time to wimp out,” said Rep. Zoe Lofgren, chair of California’s Democratic congressional caucus and a close friend and supporter of Matsui. “We need people who know what the heck they’re doing. And she does.”

Still, Levine and others lamented that recently, the party has mostly paid lip service to uplifting the next generation of leaders rather than actually giving younger voters a voice in elected office. Failing to tailor the party’s message to younger voters and instead doubling down on the party’s historic deference to seniority, he argued, will continue to drive voters away.

One potential bright spot for progressives and the anti-establishment wing of the party was in the endorsement race for the 22nd Congressional District, a Central Valley seat that Democrats hope to flip from moderate Republican Rep. David Valadao.

Assemblymember Jasmeet Bains, candidate for California’s 22nd Congressional District, speaks during a caucus meeting at the California Democratic Convention at Moscone West in San Francisco on Feb. 21, 2026.

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Assemblymember Jasmeet Bains, a physician and political moderate from Bakersfield, had been heralded as the Democratic frontrunner and boasted endorsements from the powerful Service Employees International Union of California, a labor group, and a swath of state and federal elected officials. But she still failed to capture the party endorsement after her Democratic opponent, Visalia educator and college professor Randy Villegas, built a groundswell of support and also raised more than her last quarter. The party did not endorse a candidate in the race.

Villegas said several delegates told his campaign they wanted to support him, but “there's been intimidation, outright coercion,” by Bains’ camp.

Bains, through a spokesperson, denied that she or any of her supporters coerced or intimidated any delegates into voting for her.

Jeanne Kuang and Juliet Williams contributed reporting.

This article was originally published on CalMatters and was republished under the Creative Commons Attribution-NonCommercial-NoDerivatives license.