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 the record rainfall Southern California has experienced recently has exacerbated problems repairing infrastructure 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 set forth the joint effort to solve the sewer crisis. 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 Tijuana State Public Utilities Commission (CESPT) said a pair of 42-inch pipes that send untreated water to the South Bay wastewater plant on the U.S. side of the border were repaired and ready to return to service, but a new road is in the works. construction along the border and adjacent to the PB1A and PB1B pipelines has put them out of service and will not operate at full capacity, the project will be 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.
