US and Mexico Address Tijuana Sewage Crisis
On Thursday, the United States and Mexico took collaborative steps to tackle the enduring environmental issue of untreated sewage flowing from Tijuana into Southern California.
Lee Zeldin, the Environmental Protection Agency (EPA) administrator, and his Mexican counterpart, Alicia Bárcena Ibarra, signed a Memorandum of Understanding (MOU) focusing on the consequences of cross-border wastewater pollution for environmental, public health, and national security. They reiterated their commitments and discussed new strategic projects aimed at stopping the ongoing contamination from untreated wastewater originating in coastal communities.
“What residents in Southern California really need is a solution that isn’t just a temporary fix. They deserve something more permanent,” Zeldin mentioned while in Mexico City for the signing.
The crisis at hand includes the flow of contaminated wastewater from Mexico into southern San Diego County through the ocean plume and the Tijuana River. This raw sewage carries harmful pathogens and toxic chemicals, stemming from inadequate treatment facilities near Tijuana, often leading to beach closures and frustrations for locals.
In March, California Democrats requested the EPA chief’s intervention, which led Zeldin to visit the area in April, where he heard growing concerns and urged Mexico to find a resolution.
Reflecting on his visit, Zeldin described noticing “the horrible smell that so many Southern California residents have been complaining about for a long time.” He expressed a desire to dedicate significant efforts to ensure Southern Californians receive positive news soon.
The administration identified three key priorities, which were confirmed by Mexico in the MOU signed Thursday. Zeldin highlighted Mexico’s commitment of $93 million for completing the water infrastructure projects outlined in a previous agreement.
Mexico plans to allocate $46 million in 2026 and $47 million in 2027 for the rehabilitation of wastewater treatment facilities, pumps, backup power supplies, and additional necessary equipment.
The MOU emphasizes expediting project timelines by including construction schedules for 2026 and 2027, adhering to a priority schedule for this initiative. It allows the US and Mexico to craft an agreement for any new efforts required to meet their goals.
A key element of the MOU is the intention to secure funding by December 31 and immediately implement actions through existing or newly formed Workgroups.
“This goes beyond just an agreement for 2025,” Zeldin explained. “It stems from discussions aimed at what we should achieve by 2030, 2035, and even further down the line.”
Yet, the MOU also lays out immediate steps for 2025, including a commitment to redirect sewage treated at the Arturo Herrera and La Marita Wastewater Treatment Plant to a site further upstream at the Rodríguez Dam. Additionally, Mexico has pledged to rehabilitate a wastewater collector known as the “parallel gravity lines” with an investment of around $8.42 million.
Zeldin further acknowledged President Trump’s commitment to addressing the crisis, stating that such progress “would have been impossible” without the president’s involvement. He recounted Trump’s remarks on the environmental threats to Navy seals, which underscored the urgency of the situation.
In reaction to the MOU, Tom Kiernan, president and CEO of American Rivers, considered this partnership a significant leap for the Tijuana River. He expressed gratitude for the Trump administration’s dedication to restoring the river’s former vitality.
Christan Calvert, associate director of the California River Conservation Organization, voiced optimism about the administration’s potential role in a significant turnaround for the river, reflecting the long-standing public health challenges faced by communities around the Tijuana River.
