“I want my family, my neighbors and everyone in this region to be able to breathe easy and enjoy our beaches.”
With those words, Bridget Premont stepped into a newly created role at San Diego County, tasked with coordinating the response to pollution in the Tijuana River, an environmental crisis that has affected public health, beaches and the economy of South County communities for decades.
Her appointment comes at a time of growing concern among border communities. Alongside ongoing beach closures and sewage flows crossing the border, new scientific research is raising questions about possible impacts on air quality.
At the Monday press conference announcing Premont’s appointment, Supervisor Paloma Aguirre, the former mayor of Imperial Beach and one of the strongest advocates for a more aggressive response to the crisis, said conditions continue to worsen.
“It has always been a crisis, but the scale is getting worse every day,” Aguirre said.
Aguirre noted that the new position addresses a need local leaders have identified for years: having a single person responsible for coordinating efforts across multiple agencies and levels of government. When the county Board of Supervisors approved the County Pollution Crisis Chief position, Aguirre argued that residents needed “one point of accountability” to help tackle a crisis affecting public health, the environment and the regional economy at the same time.
The job is no small undertaking. It requires aligning the work of federal, state and local agencies while maintaining communication with Mexican authorities in a watershed shared by both countries.
A river that connects two countries
The Tijuana River watershed covers nearly 1,750 square miles on both sides of the border. It begins in the mountains of northern Baja California, gathers water from streams and canyons that run through Tecate and Tijuana, crosses into the United States through the Tijuana River Valley, and empties into the Tijuana Estuary before reaching the Pacific Ocean near Imperial Beach.
According to the U.S. Environmental Protection Agency (EPA), it is one of the main entry points for transboundary pollution into California.
And it carries far more than water.
The river can transport untreated sewage, trash, contaminated sediment, urban runoff from Tijuana, industrial waste and other pollutants carried through aging drainage systems. The EPA has identified failing wastewater infrastructure, inadequate treatment capacity and rapid population growth on both sides of the border as key factors driving the problem.
For residents of Imperial Beach, San Ysidro and Nestor, the effects have become part of daily life: prolonged beach closures, persistent odors and concerns about potential health impacts.
A growing concern beyond the water
For years, public attention focused largely on ocean pollution and beach closures.
More recently, however, researchers have expanded their focus to air quality.
Scientists from UC San Diego, San Diego State University, UC Riverside and other institutions detected elevated levels of hydrogen sulfide, a gas associated with decomposing wastewater and responsible for the rotten-egg smell many residents say they have noticed for years. In some parts of the Tijuana River Valley, concentrations were far higher than those typically found in urban areas.
The findings, published in Science and later highlighted by UC San Diego, lend support to concerns long voiced by local residents: that the pollution does not remain confined to the water.
Researchers also identified hundreds of chemical compounds in the air above the valley and nearby coastline. The results are consistent with reports from residents who have described headaches, eye and throat irritation and respiratory problems during periods when odors are particularly strong.
Experts caution that viewing the crisis solely as a sewage issue paints an incomplete picture.
The Tijuana River Valley Water Quality Report 2025, prepared by San Diego Coastkeeper, documented ongoing contamination from fecal bacteria, pesticides, metals, industrial chemicals and PFAS compounds, often referred to as “forever chemicals” because they break down very slowly in the environment.
The report also found recurring evidence of contaminants associated with industrial activity throughout the watershed, suggesting that the crisis extends beyond leaks from residential wastewater systems.
For that reason, many experts say improvements to wastewater treatment are necessary but not sufficient. Addressing the contamination will require long-term investment in infrastructure, stronger controls on multiple pollution sources and sustained binational cooperation.
The diplomat chosen to lead the effort
Premont’s background helps explain why county leaders turned to a career diplomat to head the new office.
She has served as a deputy chief of mission for the United States, overseeing diplomatic and international cooperation programs. Before that, she worked in the State Department’s Office of Environmental Quality, where she participated in negotiations involving environmental and economic issues.
That experience is especially relevant because many solutions for the Tijuana River depend on agreements between institutions in both countries, as well as funding from multiple levels of government.
Her connection to border issues goes back years. From 2017 to 2021, she served as chief of political and economic affairs at the U.S. Consulate General in Tijuana and also held several assignments as acting consul general. During that period, she took part in negotiations involving cross-border pollution, water infrastructure and environmental cooperation between Mexico and the United States.
According to the county, some of that work helped secure more than $340 million in funding for projects aimed at reducing pollution and improving wastewater infrastructure along the border.
U.S. Chargé d’Affaires Bridget Premont completed her official visit to Gitega, Burundi’s political capital. On June 17, 2026. CDA Premont met with Gitega Governor Liboire Bigirimana to discuss decentralization, infrastructure, and the growing U.S. commercial presence in the province — including American energy companies working to expand electrification across the region. #USinBurundi #Gitega
— U.S. Embassy Bujumbura (@US_Emb_Burundi) June 22, 2026
During her introduction, Premont acknowledged that there are no quick fixes for a crisis decades in the making. Still, she said better coordination between agencies can help speed up progress that communities have been waiting years to see.
Her responsibilities will include coordinating federal, state and local agencies; securing funding for infrastructure projects; responding to major pollution events; overseeing transparency related to public spending, and maintaining bilingual outreach campaigns for affected communities.
The pressure on the new office will be significant. A study commissioned by San Diego County estimated that pollution tied to the river causes economic losses of up to $503.5 million each year. If conditions remain unchanged, the cumulative cost could exceed $7.9 billion over the next two decades.
For many South County residents, though, success will be measured in much simpler terms: beaches that stay open, fewer days spent dealing with foul odors and an end to the health warnings that have become a routine part of life for thousands of families living near the river.
