The Tijuana Slough at the Tijuana River Mouth ranked among California's most polluted beaches, while Playa Blanca near Tijuana was listed as the state's worst beach in Heal the Bay's annual Beach Report Card released Wednesday ahead of Memorial Day weekend.
The environmental nonprofit's 2025-26 report placed the Tijuana Slough ninth on its annual "Beach Bummer" list of beaches with the poorest summer dry-weather water quality grades because of elevated bacteria levels and chronic pollution concerns.
According to Heal the Bay, Playa Blanca and the Tijuana Slough continue to be heavily impacted by transboundary wastewater flows from Baja California, although efforts are underway on both sides of the border to reduce sewage discharges and improve infrastructure.
The report's Beach Bummer rankings were:
— 1. Playa Blanca near Tijuana;
— 2. Santa Monica Pier;
— 3. Erckenbrack Park in San Mateo County;
— 4. Linda Mar Beach at San Pedro Creek in San Mateo County;
— 5. Parkside Aquatic Park in San Mateo County;
— 6. Pillar Point Harbor's Capistrano Road Beach in San Mateo County;
— 7. Pillar Point Harbor's Harbor Beach in San Mateo County;
— 8. Marlin Park in San Mateo County;
— 9. Tijuana Slough at the Tijuana River Mouth in San Diego County; and
— 10. Clam Beach County Park at Strawberry Creek in Humboldt County.
Heal the Bay said California beaches overall maintained relatively strong water quality, with 91% earning A or B grades during summer dry conditions. However, statewide wet-weather grades declined from 67% to 61% because of rainfall, stormwater runoff and aging infrastructure, according to the report.
"No one should get sick from a weekend in our waters," Heal the Bay CEO Tracy Quinn said in a statement. "These findings are a reminder that water quality isn't just a report, it's a public health issue that affects every beachgoer and river user across California."
According to the report, 21 beaches statewide earned Honor Roll status for receiving A-plus grades in all monitored weather conditions, down sharply from 62 beaches the previous year.
San Diego County beaches receiving Honor Roll recognition included Encinitas' San Elijo State Park Pipes surf break, several Carlsbad beaches, Point Loma Lighthouse, Sunset Cliffs at Ladera Street, Mission Beach at Belmont Park, Solana Beach Tide Beach Park and Cardiff State Beach.
The report urged beachgoers to avoid swimming within 72 hours after rainfall and to stay away from storm drains, river outlets and stagnant water areas.
