Tijuana River Program Moves River Gates and Cross-Border Wastewater Work Forward
EPA’s third-quarter update reports Phase 2 river-gate construction, a completed parallel gravity line and continued work on cross-border wastewater infrastructure.
Development date: September 30, 2026
The U.S. Environmental Protection Agency’s third-quarter update on the Tijuana River sewage program reports several concrete construction milestones on both sides of the border. Phase 2 of the Tijuana River diversion-gate work began in September, a parallel gravity line was completed, and agencies continued coordinating upgrades intended to reduce untreated flows reaching the San Diego region.
The work is part of a multi-agency program involving EPA, the U.S. International Boundary and Water Commission, Mexican authorities and financing partners. EPA said the South Bay International Wastewater Treatment Plant expansion to 35 million gallons per day was completed in August 2025. The current program is focused on improving conveyance reliability, intercepting flows and strengthening the broader system that feeds treatment capacity.
EPA reported that Phase 2 of the river-gate program is being advanced alongside Phase 1 and is scheduled for completion in early 2027. Construction sequencing changed to prioritize urgent repairs to the Antiguo Force Main. The agency also said the PB-1 facility remains targeted for certification by the North American Development Bank by December 2026. These dates are targets in the public update, not guarantees of completion.
Wet-weather readiness is a major operational issue. EPA and USIBWC are coordinating with agencies in San Diego and Tijuana to assess infrastructure integrity, including conditions at Rodríguez Reservoir, ahead of the October-to-April rainy period. Heavy flows can expose weak points in collection, pumping and diversion systems, so temporary operating measures and permanent capital work must be managed together.
For the infrastructure market, the program illustrates why border-water projects demand more than treatment-plant capacity. Conveyance lines, pump stations, gates, monitoring systems and emergency-response protocols all affect performance. Procurement opportunities may be divided among U.S. and Mexican entities, and firms should verify the contracting authority and funding source for each package.
The quarterly reporting also provides a useful accountability mechanism. Stakeholders can compare promised milestones with completed work and identify where schedule changes reflect genuine field conditions. Continued publication of construction status, certification and wet-weather performance will be essential to measuring whether the system delivers sustained water-quality improvement.
Source: U.S. Environmental Protection Agency, September 30, 2026.
Representative wastewater infrastructure photograph, not a site discussed in this article. Photo: Pi.1415926535, CC BY-SA 4.0. No editorial alterations; WordPress may resize or crop for display.
