How the United States and Mexico can clean up the Tijuana River

from Deborah BrennanCalMatters

This story was originally published by CalMatters. Subscribe to your newsletters.

This article is also available in English. Read it here.

Authorities tasked with cleaning up pollution from the Tijuana River must complete improvements to wastewater facilities on both sides of the border, finance the operations, not just the construction, of those facilities and plan for the eventual reuse of wastewater, a report released Wednesday recommended.

Those are some key takeaways from the report, “The Tijuana River Pollution Crisis: A Five-Pillar Framework for Binational Solutions,” released today by the San Diego Regional Chamber of Commerce and the Prebys Foundation. Maria Elena Giner, former commissioner of the U.S. Bureau of International Boundaries, and Doug Liden, former employee of the U.S. Environmental Protection Agency, authored the report.

The paper provides an overview of how the transboundary river became one of the most polluted waterways in the country, recent efforts to clean it up, and what is still needed to clean it up.

“The continued pollution of the Tijuana River and the nearby Pacific coast is due to chronic historical infrastructure failures, inadequate operation and maintenance, and fragmented binational governance,” the report states.

The Tijuana River basin covers approximately 1,750 square miles, with nearly three-quarters of its area in Mexico and one-quarter in the United States, according to the report. It is primarily lined with concrete on the Mexican side, but extends through natural floodplains and wetlands in the Tijuana River Valley on the US side.

The United States and Mexico have administered it jointly since 1944 through the International Boundary and Water Commission. The North American Free Trade Agreement, the U.S. EPA’s Border Water Infrastructure Program and U.S. investment in Mexico helped pay for wastewater treatment, the report said.

But wastewater capacity has not kept pace with Tijuana’s population growth, and delayed maintenance and deteriorating facilities have led to “recurring breakdowns and accelerated transboundary flows since 2016, undermining much of the progress achieved through previous binational efforts.”

Over the past decade, sewage pollution from the Tijuana River has affected Imperial Beach, Coronado and other areas of southern San Diego County, dissuading beachgoers and surfers, forcing beach closures and jeopardizing Navy SEAL training in Coronado. The river also releases toxins into the air, such as foul-smelling hydrogen sulfide gas, which causes respiratory problems and other illnesses in neighboring communities.

Pathogens such as faecal coliforms, E. coli, enterococci and viruses cause gastrointestinal, respiratory and skin diseases, according to the report, creating a chronic public health risk for nearby communities and recreational users. Water analyzes also found high levels of industrial metals such as copper, nickel and zinc.

Meanwhile, 75 percent of Tijuana’s sewer network and half of its pumping stations are in urgent need of repair. Its population is projected to grow by 40 percent by 2050, and demand for drinking water is outpacing interest in wastewater treatment, according to the report.

The infrastructure on the American side was also crumbling. The South Bay International Wastewater Treatment Plant has suffered decades of deferred maintenance, with more than a third of the facility in critical condition by 2022, according to the report.

The lack of consistent funding for operations and maintenance “has led to a repetitive cycle of system failures where emergency fixes only occur after major operational disruptions,” he said.

To correct these shortcomings, the United States and Mexico should adhere to plans laid out in a series of treaties or acts negotiated through the International Boundary and Water Commission, the authors urged. They detail how the two countries should cooperate to manage the river and how to expand the capacity of sewage treatment facilities to control sewage and other pollutants.

In addition to these investments, the United States must provide annual funds for the maintenance and operation of the South Bay International Wastewater Treatment Plant. The International Boundary and Water Commission should consider a tiered pricing structure that penalizes Mexican wastewater facilities discharging into the Tijuana River and offers lower rates for flows that are properly managed, the authors recommend.

While wet weather increases river flows, the worst pollution occurs during dry conditions, so “eliminating dry-weather flows provides the greatest benefits at the lowest costs,” they note.

Rather than simply managing runoff, facilities must treat it to make it usable. “Wastewater reuse must remain a top priority for future infrastructure,” the report states.

He also called for transparency and public information, calling for a “joint bi-national communications strategy”, improving real-time beach monitoring and reporting and holding an annual “State of the River Forum”.

This article was originally published on CalMatters and was republished under license Creative Commons Attribution/Attribution-Noncommercial.