The city of Coronado faces a pervasive reality with the start of a new year: more beach closures.
From the Silver Strand shoreline to North Island, Coronado beaches were closed at the start of 2026 due to bacteria levels exceeding health standards resulting from transborder sewage pollution emanating from Mexico.
Water data by the U.S. Section of the International Boundary and Water Commission shows the Tijuana River’s flow peaked on Jan. 1 in the aftermath of a storm.
According to Frank Fisher, the agency’s public affairs officer, the South Bay plant is performing well and handling the increased flows.
“Everything that flows into the plant is treated or recycled,” he said, noting most of the river flows were stormwater not raw sewage.
These beach closures happened in the weeks after the city adopted a revised resolution for continued advocacy to resolve the crisis, renewed its local emergency resolution and identified eliminating cross-border water pollution in a discussion about its 2026 priority legislative goals.
The city’s proposed goal to “impose defined accountability measures” on Mexico for the future degradation, lack of maintenance or upscaling of treatment infrastructure is further outlined in its legislative guidelines which encourage advocacy for Mexican wastewater infrastructure projects progress and “the inclusion of defined accountability measures.”
The revised resolution also calls for the implementation of those measures as changes to the United States-Mexico-Canada Agreement (USMCA).
The resolution calls on city representatives to “…advocate for changes to the USMCA that establish expectations for the prohibition of cross-border water pollution and defined consequences for future pollution to assure that treatment and proper management of wastewater continues and keeps pace with industrial and population growth.”
The resolution was approved on Dec. 2 after a City Council discussion about ongoing advocacy efforts.
Coronado’s pollution testimony
The city submitted a letter to the United States Trade Representative (USTR) ahead of the joint review of the USMCA on July 1, 2026.
In that letter, Coronado Mayor John Duncan calls on the federal government to impose “enforceable controls” in the renegotiated agreement “so that if Mexico does not abide by its obligations, there will be real, measurable consequences.”
“Such controls could include economic, trade and monetary penalties that provide impactful consequences for a failure to maintain infrastructure in Mexico that causes pollution in the United States,” writes Duncan in the Nov. 3 letter. “The city is generally supportive of any controls, but is especially interested in further discussion with USTR on how to most effectively incentivize Mexico to continuously monitor and improve its infrastructure’s capacity and treatment capability over the long term – for the benefit of their citizens and ours.”
According to the letter, there are a variety of ways to achieve the desired outcome.
“If implemented, they would strengthen North American economic security and competitiveness, and more importantly, protect our community from future public health crises,” it says.
The U.S. trade representative is an office within the executive branch. This is not the first time Coronado has asked the White House to consider more drastic measures for Mexico. In May, the council unanimously voted to amend the city’s resolution on the sewage crisis with similar language to an Imperial Beach resolution urging restrictions on water exportation and cross-border traffic.
As of Dec. 2, the city’s updated resolution on the crisis requests: “that President Donald J. Trump execute an executive order declaring water pollution at the United States-Mexico border a national emergency and continue to prioritize and send all available resources to expedite solutions.”
During a USTR public hearing on the first joint review of the USMCA in Washington, D.C. on Dec. 5, Andre Monette, partner at Best Best & Krieger LLP, testified on behalf of Coronado, stressing the urgency in the city’s position.
Monette said population and economic growth in Tijuana beginning in the 1990s accelerated rapidly with the North American Free Trade Agreement (NAFTA) and the massive increase in trade and cross-border development continues under the USMCA.
“Between 1994, the year NAFTA was signed, and 2024, population in the city of Tijuana more than doubled and grew by almost 1.3 million people,” said Monette. “The growth and prosperity generated by NAFTA and USMCA are undeniable and very clear. Unfortunately, Mexico has not kept up with the basic infrastructure and sanitation demands that were necessary to manage population growth that came with it.”
Monette said lack of infrastructure and failure to maintain existing collection and treatment systems has created a public health crisis on the U.S. side of the border resulting in millions of gallons of raw sewage and industrial waste flowing north into San Diego, Imperial Beach and Coronado.
“It has caused noxious fumes to enter homes and schools in communities near the international border,” he added. “It has caused illness in recreational ocean users in Imperial Beach and Coronado.”
Monette said the $300 million allocated by the USMCA for infrastructure projects in the U.S. falls short of the estimated $1 billion needed for the crisis.
“The city strongly supports renewal of the USMCA and free trade,” said Monette. “However, the city asks USTR to ensure the impacts of free trade and economic prosperity are not borne by communities in the United States. There must be enforceable mechanisms for compliance to protect communities like Coronado.”
Monette proposed permanent infrastructure funding mechanisms in both the U.S. and Mexico and said revenue could be generated by having Mexico dedicate toll road funds from the new cross-border port at Otay Mesa to infrastructure work south of the border.
“…Financial incentives are one of the biggest drivers for environmental improvements in Mexico,” he added.
Following the hearing in December, Ambassador Jamieson Greer reported to Congress on the operation of the USMCA in advance of the 2026 review.
In his report, Greer identified “Increasing funding for trade, labor, and environment enforcement activities” among concerns being addressed with Mexico.
“That work remains ongoing and covers not only trade, but border and national security as well,” said Greer during a hearing held Dec. 16 and 17.
“…I want to stress that the success of the Joint Review will depend on a variety of factors, including the ambition of our USMCA partners. In addition, we must achieve outcomes that meet President Trump’s expectation,” he added.
Trump has highlighted the crisis online with a post, on Dec. 10, urging Mexico to manage its water and sewage problem calling it “a true Threat to … the United States of America!”
