US officials are expressing growing concern about sewage flows from Mexico that continue to pollute communities and beaches in Southern California despite measures taken to mitigate the problem.
The US Commissioner of International Borders and Waters, Maria-Elena Giner, said in a letter in late January that, after a visit with her Mexican counterparts and other authorities south of the border, “we have not yet saw no improvement in wastewater flows, specifically in terms of reductions in both transboundary flow to the Tijuana River and discharge to the South Bay Wastewater Treatment Plant.”
While recent record rainfall in Southern California has exacerbated problems making infrastructure repairs on the Mexican side of the border, it is not the cause of the continued flow, Giner’s letter said.
Since early 2022, untreated sewage has been flowing from the Mexican side of the border into the Tijuana River and the Pacific Ocean contaminating the water in communities like Pacific Beach on the US side of the border. In 2022, The US and Mexico signed a pair or agreements, Declaration of Intent and Act 328, which describe the joint effort to solve the sewer problem. As part of that agreement, Mexico pledged $144 million over five years in rehabilitation efforts.
Repairs to PB1A underway at Matadero Cañon, MexicoPhoto courtesy of the North America Development Bank
The State Commission of Public Services of Tijuana (CESPT) has said a pair of 42 inches. The pipes, PB1A and PB1B, which send untreated sewage to the South Bay International wastewater plant on the US side of the border, had been repaired and were ready to come back online, but the ongoing highway construction along the border and next to the pipelines has brought them. Out of service. CESPT said they will not be operating at full capacity until the project is completed in March.
“As an immediate measure, I have stressed to the state and federal governments of Mexico the importance of returning to the wastewater flow levels experienced prior to the July 2022 PB1A pipeline rupture,” Giner said in his letter.
He also said record rainfall in 2023 and the impacts of this year’s rain have contributed to high water levels and continued transboundary flows of sewage. A side effect of heavy rain, however, is further dilution of untreated sewage.
Procurement will begin in March for the PB1 pump station rehabilitation contract which is the first part of a comprehensive project to eliminate border sewage flows. The IWBC says if the overall project is on schedule to bring the stream into compliance with permits by August, but further delays would complicate that timeline.
