San Diego, CA
Pollution from the Tijuana river affects air quality in San Diego, finds study
The 120-mile Tijuana River flows from Baja California into the United States and discharges millions of gallons of wastewater—including sewage, industrial waste and runoff—into the Pacific Ocean every day, making it the dominant source of coastal pollution in the region.
Wastewater pollution has been an ongoing problem for decades and is so severe that the nonprofit environmental group American Rivers recently named the Tijuana River America’s second most endangered river.
A new study from the University of California San Diego examines how pollutants in wastewater travel and are transmitted in the atmosphere through coastal aerosols.
In the study, researchers found that a mixture of illicit drugs, drug metabolites, and chemicals from tires and personal care products aerosolize from wastewater and are detectable in both air and water. The results appear in Science Advances.
The paper’s lead author, Adam Cooper, collected samples from the air and water at various points along the coast of San Diego County, including the U.S.-Mexico border, Imperial Beach and the Scripps Institution of Oceanography in La Jolla.
Cooper, who graduated last spring with a doctorate in chemistry, was a member of Assistant Professor of Chemistry and Biochemistry Jonathan Slade’s group, and collected the samples as part of a field study with Distinguished Professor of Atmospheric Chemistry Kimberly Prather’s lab.
Prather, who holds a joint appointment at Scripps Oceanography and the Department of Chemistry and Biochemistry at UC San Diego, had been studying the air pollution impacts of the Tijuana River for several years. Cooper was able to join her team’s comprehensive sampling campaign across multiple sites from January to March of 2020.
Even though the samples were taken in 2020, the findings are still relevant because little has changed in how sewage released from the river is processed. In fact, pollution from the river has been an ongoing problem for more than 50 years.
“The Tijuana River region is a very dynamic environment with implications for public health, environmental policy and international relations between the United States and Mexico,” stated Cooper.
“Ours is one of the most comprehensive studies to date investigating water-to-air transfer of these pollutants.” The study looked at two aspects of wastewater pollution: the source and the concentration of pollutants along the San Diego County coastline.
To determine the origin of the pollutants, Slade’s lab used a compound they knew came from sewage: benzoylecgonine (BZG), a stable metabolite of cocaine, primarily produced when people use cocaine and then excrete it in urine.
They found that after rainfall, BZG levels in Imperial Beach ocean water spiked in correlation with increased Tijuana River flows, while BZG levels in aerosols spiked in correlation with enhanced sea spray aerosol emissions.
Correlating 11 other pollutants to BZG in aerosols allowed the team to determine which ones behaved similarly in the environment and likely originated from the same wastewater source. The results showed a high correlation between BZG; methamphetamine; octinoxate, a UV filter used in sunscreen; and dibenzylamine, a compound used in tire manufacturing.
The second part of the study measured pollutant concentrations along the coastline in the water and air. Overwhelmingly, they found that these pollutants were higher in the Tijuana River water than in the ocean, and higher in the water and aerosols in the Imperial Beach region than in La Jolla.
Although the amounts of some pollutants, like cocaine, were minuscule, others were more prominent, like octinoxate, which can break down into more toxic components.
In some cases, the octinoxate levels were comparable to measurements made directly above wastewater treatment plant vats, meaning that in some ambient conditions at the coast, the concentrations of pollutants that people are inhaling can be comparable to a worker at a wastewater treatment plant.
“It’s been shown that octinoxate can degrade DNA when exposed to light,” stated Slade. “And if it’s in these tiny aerosols we’re breathing in, it can get deep into our lungs and pass into our bloodstream. That’s very concerning, especially considering the high levels at which we found it in the air.”
The study shows that the closer you are to the Tijuana River, the more likely you are to be exposed to the pollutants it carries, even though the amounts are still relatively small—on the scale of tens of nanograms per hour. This may not seem like much if your exposure is limited to a few hours, but residents living close to the border are inhaling these chemicals over years, even decades.
Many residents have complained of respiratory illness, insomnia and headaches, and several San Diego beaches have been closed almost continuously for the last three years because of high levels of bacteria from wastewater runoff.
Although the paper doesn’t draw any conclusions about the detrimental effects on the environment or human health, Slade and Cooper emphasize the need for more research, better infrastructure and cross-border collaboration.
“Often the sewage crisis is considered a water issue—and it is—but we show that it’s in the air too. Truthfully, we don’t yet know the acute health effects,” stated Slade. “But the numbers we report can be incorporated into models to help us better understand what we’re breathing in and how much we’re exposed to.”
Cooper was so influenced by his work at UC San Diego that he is now a Science and Policy Technology Fellow with the California Council on Science and Technology, working with State Senator Ben Allen.
“The solutions to the cross-border sewage crisis aren’t constrained by technical challenges,” stated Cooper. “They’re constrained by political challenges and policy issues. We have to motivate decision-makers to make the right investments.”
In addition to better infrastructure, more public awareness is crucial to improving the region’s water and air quality, including understanding the downstream effects of the products we use, such as sunscreens and tires.
“Although our study focuses on the Tijuana River, there are other notable sources of wastewater and pollution run-off in Southern California, including wastewater treatment outfalls, the San Diego River and the Los Angeles River,” said Slade, who also noted that “turbulence in rivers and streams may aerosolize wastewater, requiring further study.”
Coastal port environments are extremely dynamic and complex, but these pollution issues are not relegated just to the San Diego-Tijuana region. They pose a global hazard.
An estimated 80% of all global wastewater is untreated. Of the portion that is treated, many plants remove bacteria, but not chemical pollutants. These chemicals remain in the water, which is released into rivers, lakes and oceans, traveling around the world through waterways and in the atmosphere.
“The global surge of untreated wastewater entering lakes, rivers and oceans poses a growing health threat. Aerosolization of this polluted water exposes billions of people through airborne transmission, reaching far beyond those in direct contact and impacting countless others who inhale contaminated air that can travel for many miles,” stated Prather.
“We are continuing our studies in this region to better understand the short and long-term health impacts of inhaling this newly identified source of airborne pollution.”
More information:
Adam Cooper et al, Identifying Wastewater Chemicals in Coastal Aerosols, Science Advances (2025). DOI: 10.1126/sciadv.ads9476. www.science.org/doi/10.1126/sciadv.ads9476
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San Diego, CA
San Diego County Supervisor Jim Desmond to propose first-time homebuyer program
SAN DIEGO (CNS) – A San Diego County supervisor will introduce a first-time homebuyer pilot program focused on down-payment assistance, interest-rate buy-downs and partnerships during the regular Tuesday meeting.
Supervisor Jim Desmond’s proposal includes directing Chief Administrative Officer Ebony Shelton’s office to assess how the program would benefit new homebuyers in the unincorporated area.
That analysis would cover:
- opportunities for public-private partnerships, including financial institutions as a way to secure better terms for applicants
- potential down-payment assistance
- interest rate options to improve mortgage affordability
- criteria designed to complement two existing first-time programs that help with down payment and closing costs, and down payments for moderate- income residents
- an estimate of how much the program would cost, along with safeguards and strategies to lower risk
The CAO and staff would report back to the Board of Supervisors within 120 days.
Desmond briefly discussed the proposal during his final State of North County speech on March 12.
His board letter states that data from the California Association of Realtors shows that only 13% of county households can afford to purchase a median-priced home as of last year.
Along with home prices, factors such as stagnant wage growth, limited inventory and higher interest rates “have combined to push homeownership out of reach for a significant portion of the local population,” Desmond stated in the board letter.
In a video promoting the measure, Desmond said “the very people who serve our communities are being priced out.”
He added that owning a home “isn’t about property — it’s about dignity, it’s about stability. It’s also about giving families a foundation to build wealth and put down roots.”
Desmond, first elected as the District 5 supervisor in 2018, will complete his second term in January. The Republican is running for Congress in the 48th Congressional District, seeking to succeed Rep. Darrell Issa, R- Bonsall.
The proposal is item No. 25 on the board agenda. The meeting will begins at 9 a.m. in the Board Chamber of the county Administration Building, 1600 Pacific Highway.
Copyright 2026, City News Service, Inc.
San Diego, CA
Historic Tall Ship Faces Eviction in San Diego
A longtime fixture in Chula Vista Harbor is being told to shove off. The 137-foot schooner Bill of Rights, a replica tall ship that’s doubled as a floating classroom in San Diego’s South Bay for decades, has been ordered to vacate its berth by May 5, according to its nonprofit operator, the South Bayfront Sailing Association. The group says Safe Harbor Marina, acquired last year by Blackstone Infrastructure, terminated the lease without giving a clear explanation, NBC San Diego reports. The Bill of Rights has been docked in Chula Vista since 2013.
The 1971-built vessel hosts youth programs that teach seamanship, navigation, and teamwork, with students as young as 10 standing watch and steering under supervision. With eviction looming, supporters have launched a national letter-writing push and an online petition, and Chula Vista’s mayor and several city council members have publicly backed keeping the ship in place. “All tall ships from all over America know that Chula Vista exists—they’re all writing letters,” says Susan Johnson of the South Bayfront Sailing Association. “People are reaching out to elected officials and even contacting Blackstone directly.”
For now, scheduled visits from Scouts, Navy Sea Cadets, and other student groups are still on the calendar. “We primarily do training for at-risk youth, US Navy Sea Cadets, and ROTC,” Captain Don Johnson, a disabled Vietnam veteran, tells 10 News. “Basically, to preserve maritime history. To provide education for youth.” He says he’s “optimistic” the community response will keep the Bill of Rights from sailing off for good. “I’ve had this dock built for a tall ship because there aren’t places for it,” Johnson says. “If they do indeed evict us, which they’ve said they’re doing, I have nowhere to go.”
San Diego, CA
The Streamline: ICE agents to assist TSA at airports across the US
Here is what you need to know in the March 23, 2023, Streamline newsletter:
The Trump administration has ordered ICE agents to airports across the U.S. to help shorten security lines as the partial government shutdown surpasses the 40-day mark.
Just as last week’s heat wave comes to an end, another round of high temperatures is coming back to San Diego County. Max Goldwasser’s microclimate forecasts will help you get ready for this week’s warm weather.
In your consumer news, we’ve got details on the “Buy Nothing Project,” a global movement that is connecting people with the things they need for free.
WEEKEND WRAP-UP
THE STREAMLINE
WATCH — ABC 10News brings you The Streamline for Monday, March 23 — everything you need to know in under 10 minutes:
The Streamline: Monday, March 23
TOP STORY
ICE agents were expected to begin handling some security duty at numerous U.S. airports Monday amid an ongoing partial government shutdown that has sidelined many Transportation Security Administration officers, with border czar Tom Homan in charge of the effort.
Federal officials said Sunday that border czar Tom Homan would be in charge of the effort to use immigration enforcement personnel to supplement security at airports amid the shutdown, which has left roughly 50,000 TSA employees working without pay, contributing to increased absenteeism and staffing shortages at airports nationwide.
Early Monday morning, ABC News — citing sources — published the following list of airports where ICE agents would be deployed:
- Chicago-O’Hare International Airport
- Cleveland Hopkins International Airport
- Hartsfield-Jackson Atlanta International Airport
- Houston’s William P. Hobby Airport
- Houston’s Bush Intercontinental
- John F. Kennedy International Airport (New York)
- LaGuardia Airport (New York)
- Louis Armstrong New Orleans International Airport
- Luis Munoz Marin International Airport (San Juan, Puerto Rico)
- Newark Liberty International Airport
- Philadelphia International Airport
- Phoenix Sky Harbor International Airport
- Pittsburgh International Airport
- Southwest Florida International Airport (Fort Myers, Florida)
It was unknown if San Diego International Airport would be added to the list.
Meanwhile, some local officials balked at the Trump administration’s announcement, including a top TSA official at San Diego International Airport.
“I have no idea how they can contribute at an airport unless it was for intimidation purposes,” Aaron Vazquez, a TSA lead transportation security officer at SAN and assistant airport steward for the American Federation of Government Employees Local 1260 in San Diego, told City News Service on Sunday. “What are they going to do, find somebody and shoot them?”
Vazquez said his job is to make sure travelers are not a threat to security, which has nothing to do with immigration enforcement.
“I don’t want them anywhere near the checkpoint and officers that I’m in charge of. I don’t want them interfering with what the officers are trying to do,” Vazquez told CNS.
“I don’t need an ICE agent telling passengers what to do. We are trained to be nice to passengers. They are law enforcement so they are armed. TSA is not,” he added.
City Councilwoman and Airport Authority Board Member Marni von Wilpert also objected to the idea.
“ICE’s aggressive, abusive conduct makes us less safe. Putting ICE in our airports will make travel more chaotic, more stressful, and less secure — not better,” she said. “ICE has already shown it refuses to follow the law and respect our communities — so I’m deeply concerned about what this deployment will mean for San Diego travelers and the thousands of workers at San Diego International Airport.
“… The solution to long security lines and airport delays is simple: Congress needs to properly fund and staff TSA now,” von Wilpert added.
“.. I have been in touch with San Diego Airport Authority staff and legal counsel. We do not yet know the full scope of ICE’s plans at the airport, but we are working to get answers and minimize disruption and anxiety for travelers and our workforce.”
Rep. Scott Peters, D-Poway, posted a photo of long lines at the airport on Sunday with the following message:
“View from the San Diego airport at 6:30 this morning. It doesn’t have to be like this. I have a bill to pay TSA workers, Coast Guard and emergency management without adding more to ICE and Border Patrol. Easy, right? But Trump won’t allow it. As the DHS shutdown drags into nearly 40 days, federal workers and travelers shouldn’t have to suffer from Republican inaction.”
Homan told CNN’s “State of the Union” on Sunday that the effort was about “helping TSA do their mission and get the American public through that airport as quick as they can while adhering to all the security guidelines and the protocols.”
“We’re simply there to help TSA do their job in areas that don’t need their specialized expertise, such as screening through the X-ray machine,” he said. “Not trained in that? We won’t do that. But there are roles we can play to release TSA officers from the non-significant roles, such as guarding an exit so they can get back to the scanning machines and move people quicker.”
On Saturday, President Donald Trump said he would order ICE agents to assist with airport security if Congress did not immediately reach an agreement to fund TSA officers.
In a social media post, Trump said ICE agents could also be tasked with making immigration arrests at airports.
“If the radical left Democrats don’t immediately sign an agreement to let our country, in particular, our airports, be FREE and SAFE again, I will move our brilliant and patriotic ICE agents to the airports where they will do security like no one has ever seen before,” Trump wrote on Truth Social.
The proposal comes as a partial government shutdown has left roughly 50,000 TSA employees working without pay, contributing to increased absenteeism and staffing shortages at airports nationwide.
Administration officials said about 10% of TSA workers failed to report for duty on some recent days, compared to typical rates of less than 2%.
“Officers have to take matters into their own hands and not come to work,” Vazquez said. “They are stressed, they are coming to me saying `what can I do?’ They can’t afford gas to get to work.”
The usual un-planned absence call-out before the shutdown was about 20 officers per day in San Diego. Now there are about 70 to 80 officers per day who are not going to work, according to Vazquez.
“They (ICE agents) can monitor traffic of the passengers to make sure they don’t get out of line or go through the stanchions,” Vazquez said. “I don’t understand what we need help with if it’s not people that are able to screen the passengers.”
Meanwhile, travelers are being warned to expected delays. The San Diego County Regional Airport Authority issued a travel advisory Sunday for passengers traveling out of the city’s airport.
“Passengers traveling out of San Diego International Airport are encouraged to check their flight status before coming to SAN and plan to arrive at least two hours before their flight,” airport spokeswoman Nicole Hall said Sunday, the second day the airport was experiencing delays.
“Checkpoint wait times and flight scheduling are subject to the operations of our federal and airline partners. These operations are, at times, affected by the federal government shutdown.”
Hall said an influx of seasonal spring break travelers was also affecting wait times, which could take up to one hour during a “fluid situation.”
“We appreciate the ongoing commitment from TSA, FAA, and our partner airlines to maintain the safety and reliability of the national transportation system during this challenging time,” Hall said. “Our focus remains on ensuring a safe and efficient airport experience.”
Travelers to SAN were encouraged to plan ahead and arrive two hours before domestic flights and three hours prior to international departures.
Travelers can check flight status updates at https://www.san.org/Flights/Flight-Status.
The average wait time is about 20 minutes to get through airport security at SAN when fully staffed with a maximum wait time of 30 minutes, but some wait times on Saturday were up to an “unheard of” 80 minutes, according to Vazquez, who said “Saturdays are usually chill.”
Before the shutdown, about 500 to 550 officers were available to screen each day in San Diego.
Story by City News Service
MICROCLIMATE FORECASTS
Coasts
Inland
Mountains
Deserts
BREAKING OVERNIGHT
President Trump on Monday morning announced he is ordering the postponement of airstrikes on Iran’s energy facilities because of what he cited as “very good and productive” talks with Iranian leadership to end the war.
The president said the pause would last five days; several days ago, Trump set a deadline for Iran to reopen the Strait of Hormuz or the U.S. would “obliterate” Iranian power plants.
In response, Iran issued its own threat of laying mines across the entire Persian Gulf.
Trump calls for five-day pause in strikes on Iranian power plants, energy sites
CONSUMER
An online platform is helping people turn to their neighbors instead of stores for all sorts of items — for free!
WATCH — Consumer reporter Marie Coronel explains how the “Buy Nothing Project” is not only connecting community members, but also saving them money:
How the ‘Buy Nothing Project’ is helping consumers find necessities for free
WE FOLLOW THROUGH
The escalating conflict in the Middle East is driving up fuel prices nationwide, and in the North County, several Oceanside gas stations have already surged past the six‑dollar mark.
AAA reports that the average price for a gallon of regular gas in San Diego County has climbed to $5.86 — up $1.20 from this time last year. Meanwhile, the national average is creeping closer to $4.
WATCH — Reporter Jane Kim spoke with some San Marcos residents who are finding ways to cope with the higher costs cutting into their budgets:
Gas prices in San Diego County hit highest levels since 2023 as the war in Iran impacts crude oil costs
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