The United States and Mexico have reached a new agreement outlining additional actions and timelines in addressing the ongoing Tijuana sewage crisis.
Under the new agreement, known as Minute 333, Mexico will explore expanding its main wastewater treatment plant, plan for population growth, and construct a sediment basin. The US is not obligated to any additional construction projects or funding under the treaty minute.
Minute 333 is an effort to coordinate infrastructure projects, improve monitoring, and address long-standing gaps in planning and maintenance on both sides of the border, said David Fotouhi, deputy administrator of the Environmental Protection Agency (EPA), during a press briefing.
The agreement itself, however, acknowledges that the crisis will not be resolved immediately and conditions all actions on the availability of funding and resources.
“To be crystal clear, this human health and ecological crisis will not end solely with the swipe of a pen,” Fotouhi said. “The next step is for both nations to faithfully implement the agreed upon items in Minute 333. Each time a project is completed, we get one step closer to ending this crisis for good.”
Mexico’s infrastructure commitments
Under the agreement, Mexico must prepare a Tijuana water infrastructure master plan within six months to better align wastewater capacity with population growth.
Tijuana has in recent years faced rapid growth, which strained the already struggling wastewater infrastructure on both sides of the border. Leaders and advocates for the issue have urged for a solution that addresses future projected population numbers.
Minute 333 also requires new feasibility studies to evaluate construction of an ocean outfall at the San Antonio de los Buenos (SAB) Wastewater Treatment Plant and expansion of the SAB plant from 18 million gallons per day (MGD) to 43 MGD.
The feasibility studies will be conducted within the next three months.
Mexico also agreed to construct a sediment basin in Matadero Canyon (also known as Smuggler’s Gulch) before the 2026-27 rainy season, a project intended to reduce the flow of sediment across the border. Sediment flows from Mexico have long plagued international wastewater treatment infrastructure in the US.
Mexico will also construct the Tecolote-La Gloria Wastewater Treatment Plant, which will have a capacity of 3 MGD, by December 2028.
US commitments
The Minute does not outline any new construction projects for the US, and instead focuses on processes and oversight of international wastewater.
Specifically, it requires that the US participate in an interagency, binational “Minute 333 Work Group,” review Mexico’s feasibility studies, and work with Mexico to establish procedures, schedules, and cost-sharing for things such as spill monitoring systems, dredging operations in the Tijuana River, and trash and sediment projects.
An operations and maintenance (O&M) account will be created with NADBank to set aside a portion of any future dollars provided to Mexico to be held for future O&M costs.
Meanwhile, the US is currently rehabilitating and expanding its South Bay International Wastewater Treatment Plant (SBIWTP), which will bring its maximum capacity from 25 MGD to 50 MGD, with a maximum peak capacity of 75 MGD.
The initial expansion was projected to take two years from its launch in the fall of 2024, but it was fast tracked in May 2025, when EPA Administrator Lee Zeldin announced a 100-day timeline. The full expansion is slated for completion by the end of 2027.
Smaller projects the US agreed to in former negotiations have also been fast-tracked this year.
“Great progress has been made this year to achieve the 100% solution to the Tijuana River sewage crisis, but it would have all been for nothing if we don’t take the appropriate steps to account for the inevitable population growth of Tijuana and surrounding areas,” said EPA Administrator Lee Zeldin in a statement. “That’s what Minute 333 achieves. We have set the framework for tremendous steps to be made, and we now look forward to very quickly hitting the ground running to implement the mutually agreed upon actions.”
Yah great more talking and discussing is just what we need!