The treatment plant at Punta Bandera, about five miles south of the border, was rebuilt in 2025. When U.S. officials toured it on April 4, 2025, it was in the final stages of starting back up, expected to meet Mexican standards within two to three weeks while treating 18 million gallons a day.
Why it matters
What this plant cannot treat goes onto the shoreline at Punta Bandera and drifts north to Imperial Beach. It is the largest source of dry-season beach closures, so how much of its inflow it actually treats decides how much of the year the water here is closed.
Where it stands
Done, and not enough. The rebuilt plant treats about 18 million gallons a day, roughly half of what it receives. The rest is still discharged at Punta Bandera.
Expanding it to about 43 million gallons a day, and adding an offshore outfall so discharges no longer land on the beach, are both under study rather than funded.
Who's responsible
CESPT, the Baja California state water utility, with Mexico's federal agencies.
What to watch
Whether the expansion and the outfall move from study to a funding plan. Until one of them does, the rebuild has halved the problem rather than ended it.
Related
Punta Bandera outfall and expansion. What reaches the ocean.
Sources
- U.S. EPA, Minute No. 333, for current capacity and the expansion study
- Coronado Eagle, Mayor's Corner, August 2026, on the plant treating about half its inflow
- USIBWC, letter to stakeholders, April 9, 2025, on the April 4 tour of the plant