Both the United States and Mexico are making progress on actions aimed at solving the Tijuana River sewage crisis, according to the U.S. Environmental Protection Agency (EPA).
Last December, Mexico and the U.S. signed an agreement intended to solve the border sanitation problem plaguing the San Diego and Tijuana metropolitan areas. The signing of Minute No. 333, as the agreement is called, targeted the decades-long Tijuana River sewage crisis that has long been a point of contention between the U.S. and Mexico.
Mexico, US sign accord to solve toxic sewage crisis in Tijuana and San Diego
On June 30, more than six months after Minute No. 333 was signed, the EPA published its second quarterly update for 2026 “detailing the implementation of two historic agreements signed with Mexico in 2025 to permanently end the years-long Tijuana River sewage crisis.”
The other agreement the EPA was referring to is a bilateral memorandum of understanding that was signed in July 2025 and which, together with Minute No. 333, seeks to permanently fix the problem of Mexican sewage flowing into the Pacific Ocean off the coast of southern California after crossing the border via the Tijuana River. Mexico committed to allocating US $93 million to sewage system projects as part of the MOU.
In its second quarter update, the EPA said that the Trump Administration has been “working at a relentless pace to bring relief to the people of San Diego, who for decades have been inundated with sewage from Mexico via the Tijuana River Channel and the coast.”
“The decades-long crisis has closed beaches, polluted water, fouled the air, and caused hopelessness,” said the agency headed by Lee Zeldin.
“Since his first visit in April 2025, EPA Administrator Lee Zeldin has moved at ‘Trump Speed’ to identify, secure, and implement a 100% solution to permanently and urgently end the crisis, resulting in the signing of a Memorandum with Understanding (MOU) with Secretary of the Environment and National Resources of Mexico Alicia Bárcena Ibarra in Mexico City in July 2025,” the EPA said.
“Building on that momentum, the U.S. and Mexico agreed to Minute 333 in December 2025, which laid out a host of actions, including additional projects, research, and planning for operation and maintenance of critical systems to account for future population growth in Tijuana,” the agency said.
EPA: US and Mexico have taken ‘important actions to end the sewage crisis’
The EPA said that since it published its previous quarterly update in March, “the Trump Administration and Mexico have taken a number of important actions to end the sewage crisis.”
The agency highlighted that it released “previously agreed to Border Water Infrastructure Program (BWIP) funds to begin construction on Pump Station 1 (PB-1) [in Tijuana] and Tijuana River Gates projects.”
“Mexico is also advancing procurement and construction of critical sewer line and pump station rehabilitations,” the EPA said.
“Additionally, both the U.S. and Mexico have advanced progress on a suite of actions agreed to in Minute 333, including infrastructure projects, research studies, and planning for operation and maintenance (O&M) of critical sites and systems that will account for future population growth in Tijuana,” the EPA said.
The agency provided a number of specific details on actions taken, or being taken, to solve the cross-border sewage problem.
The EPA said that Mexico began construction of PB-1 on April 27, and that “this essential project” will “eliminate potential catastrophic discharges and increase total pumping capacity to 80 million gallons per day (MGD).” The project is slated for completion in November 2027.
The EPA also said that the Tijuana River Gates project “will eliminate at least 5 MGD of sewage from entering the Tijuana River.” The agency said that phase one of the project is expected to be completed by mid-July 2026, while phase 2 is currently in procurement and is expected to be finished at the end of January 2027.
The EPA said that the PB-1 and Tijuana River Gates projects “will help improve wastewater reliability, prevent spills, manage flow, reduce pollution, and lower the risk of flooding.”
In addition, the U.S. agency highlighted that since “surpassing its 2026 funding commitment, Mexico is advancing procurement and construction of critical sewer line and pump station rehabilitations, which will prevent sewage discharges into the Tijuana River.”
Among other “actions” related to Minute No. 33, the EPA noted that “Mexico completed the sediment basin at Matadero Canyon in May 2026, meeting the pre‑rainy‑season construction goal and reducing sediment and debris impacts,” and that “the Minute 333 Work Group is also advancing a scope of work for a transparent, real-time binational monitoring system to track flow inputs and outputs to the Tijuana River, strengthening accountability between both countries.”
The agency also said that “the binational O&M Workgroup continues developing long-term strategies to ensure critical infrastructure is maintained along the border,” and that “the binational Minute 333 Work Group reviewed existing engineering and financial feasibility studies for an ocean outfall at the San Antonio de los Buenos Wastewater Treatment Plant” in Tijuana.
On the U.S. side of the border, there is “continued progress towards expanding the South Bay International Wastewater Treatment Plant (SBIWTP) to increase treatment capacity to 50 million gallons per day,” the EPA said.
Zeldin said in late June that “we’re continuing our relentless pace in ensuring that Mexico meets its funding commitments, that projects are being built on the tightest possible timelines, and that actions are being taken to plan for future population growth in the [Tijuana-San Diego] region.”
“Safeguarding human health and the environment is EPA’s foremost responsibility, and we are committed to ensuring that every American has clean air, land, and water,” the EPA administrator said.
With reports from La Jornada
