Mexico's ambassador to the United States pledged during his first San Diego visit to keep working on the Tijuana River pollution crisis, touring the South Bay International Wastewater Treatment Plant as cross-border sewage continues to plague the region. Roberto Lazzeri called the long-running crisis one of the top priorities of the binational agenda and said Mexico is working to secure the resources needed for infrastructure fixes on its side of the border.
Lazzeri, Mexico's ambassador to the United States, was interviewed at the Mexican consulate in San Diego on October 30, as reported by the San Diego Union-Tribune. During his San Diego trip he also met with U.S. Customs and Border Protection, U.S. Border Patrol and the International Boundary and Water Commission.
A Tour Focused on Sanitation
Lazzeri toured the South Bay plant and the surrounding area alongside Chad McIntosh, commissioner of the U.S. International Boundary and Water Commission, who led the tour. A spokesperson for the commission, Frank Fisher, said the conversation centered on the San Diego–Tijuana sanitation issue, and that Lazzeri expressed interest and support for solving the pollution crisis, per the Union-Tribune's reporting.
The South Bay plant treats sewage flowing from Tijuana. As Voice of San Diego reported, the binational watershed has more than 2.8 million people, and the region has experienced accelerated population growth and depleted sanitation infrastructure. But the facility was never built to handle everything flowing through the river. The plant was built to treat sewage — it wasn't designed to remove the industrial chemicals and heavy metals found in the water.
Aging Pipes, Industrial Chemicals
The scale of Tijuana's infrastructure problem is stark. A 2025 study found more than 2,360 miles of sewer mains in the city, 57 percent of which are failing due to age and wear, per the same Voice of San Diego report. San Diego Coastkeeper's water-quality testing has also found industrial chemicals, heavy metals and pesticides flowing into the Tijuana River on a regular basis, with each round of testing typically turning up 10 to 20 chemicals that the outlet's report says could only come from factories.
Hydrogen sulfide levels in the Tijuana River Valley have also drawn alarm. A 2025 study measured peak concentrations roughly 4,500 times what would be expected in an average U.S. city, the report notes. That pollution carries a human cost too — a 2024 survey found 69 percent of respondents reported health problems they associated with it, according to the same Voice of San Diego account.
Repairs, Funding Gaps and New Projects
Fixing the South Bay plant alone won't resolve the crisis. The facility needs nearly $900 million in repairs but faces a $300 million funding shortfall, Voice of San Diego's reporting found. Separately, wastewater facilities on both sides of the border have failed over the past decade, releasing hundreds of millions of gallons of raw sewage into the river, according to the Los Angeles Times. The federal government has dedicated about $650 million toward repairing and replacing aging wastewater infrastructure, the Times reported.
On the Mexican side, officials overhauled the San Antonio de los Buenos wastewater plant in Tijuana in an effort to reduce sewage discharge affecting border communities, per the Union-Tribune. That plant partially came online after nearly eight months of delays, malfunctions and redesigns, according to Border Report. Border Report separately reported that communities had seen little to no relief and beaches remained closed.
A 2025 Agreement
Mexico and the United States signed an agreement in 2025.
County Dollars and Trade-Deal Pressure
On the U.S. side of the border, San Diego County supervisors have already taken their own steps. The board voted 4-1 in September to spend $1.8 million designing a system to divert and treat Tijuana River water before it reaches local communities, the Los Angeles Times reported. Supervisors separately and unanimously approved $4 million for immediate repairs to a sewage hot spot on Saturn Boulevard. A proposed half-cent county sales tax tied to the November ballot could generate $360 million annually, with about $80 million a year earmarked for Tijuana River improvements — revenue officials say could support $700 million to $1 billion in bonds for new sewage treatment facilities, per the Times.
California state Assemblymember David Alvarez, who represents border communities, has said a renewed trade agreement should include binding environmental standards and accountability, according to the Union-Tribune. San Diego County elected leaders and environmental advocates have urged that solutions, accountability measures and protections for cross-border pollution be built into a renewed trade pact, which is subject to an annual review process. Lazzeri, for his part, said he does not believe the pollution crisis needs to be written into the trade treaty itself, arguing it is already a shared priority between the two nations.
