Beach closures and health warnings are continuing across parts of Southern California as sewage flowing from Mexico contaminates coastal waters, raising concerns among residents, health officials, and local leaders.
In Coronado, near San Diego, county officials have posted advisories warning people to avoid contact with ocean water due to pollution tied to the Tijuana River. Signs along the shoreline caution that entering the water could cause illness.
The Tijuana River carries untreated wastewater from Mexico into the United States before currents push contaminated water north along the California coast. Reports indicate that tens of millions of gallons of sewage-tainted water can enter the Pacific Ocean daily, affecting beaches throughout the region.
The contamination has reached high-profile areas, including waters near the historic Hotel del Coronado, where unsafe conditions have forced repeated closures.
Health experts say the pollution poses risks in both the water and the air. Hydrogen sulfide gas associated with sewage can irritate the eyes and respiratory system and may cause more severe health effects at higher concentrations, according to the Centers for Disease Control and Prevention. Exposure to contaminated water can also trigger gastrointestinal illnesses, while airborne toxins have been linked to headaches and breathing problems.
Community advocates and medical professionals say children have been especially affected. Some families have reported worsening asthma symptoms, skin irritation, and other health issues they believe are tied to the pollution.
Residents living near the coast have also complained about persistent odors.
“There’s a really unpleasant sewage odor outside that drifts into my apartment,” one Reddit user wrote, Fox 4 KDFW reported. “This has been happening for months with no improvement.”
“It’s nasty,” another user added, per Fox 4. “This has been going on for too long.”
Local officials and environmental groups say the crisis has intensified in recent months. During a briefing hosted by the Tijuana River Coalition, advocates, healthcare workers, and environmental experts discussed the growing public health concerns and efforts to accelerate cleanup projects.
“As so many folks know, this is one of the longest standing public health issues facing the United States,” said Courtney Baltiyskyy, vice president of public policy and advocacy at the YMCA of San Diego County, per Cal Matters. “It is a unique issue because it’s on the border between Mexico and the United States and in a place with thriving commerce and extremely unique ecological, natural resources. But we know that the threat to our communities is dire. And it’s worse than ever before.”
Officials said sewage pollution has sickened swimmers and surfers, contributed to beach closures, and affected Navy SEAL training operations at Naval Amphibious Base Coronado. Air quality concerns have also grown as hydrogen sulfide levels increase in nearby communities.
Longtime Coronado residents say the crisis has transformed an area once known for its beaches and tourism.
“It was heaven on Earth, and now I call it paradise lost,” retired surgeon and surfer Whitney David told The Wall Street Journal.
Visitors have encountered warning signs along beaches that caution against entering the water. Kristin Cohen, a visitor from New Jersey, said she had planned to bring her young daughter to the beach before seeing a notice that read, “Water Contact May Cause Illness.”
“I guess we can’t do that, babe,” she said, the New York Post reported.
Others say the smell alone has become disruptive. Larry Delrose, entertainment director at the Coronado Shores condominium community, said he regularly shuts his windows to block what he described as sewer-like odors.
San Diego County Board of Supervisors member Paloma Aguirre has called the contamination the “worst environmental disaster in the United States” and urged California Gov. Gavin Newsom to declare a state of emergency, per the Post.
“We are breathing in toxic gases, and we can’t wait any longer,” Aguirre said in a video posted to Instagram. “Please declare a State of Emergency for the Tijuana River crisis.”
“Our children are waking up with headaches, our seniors are struggling to breathe, and our families are prisoners in their own homes,” she added.
The issue has also drawn national attention. President Donald Trump has urged Mexico to address untreated wastewater flowing into the United States, calling it a threat to nearby communities. Federal officials have said the administration is working with Mexico on wastewater infrastructure improvements and expansion projects aimed at reducing future contamination.
According to the Environmental Protection Agency, U.S. and Mexican officials signed agreements in 2025 intended to accelerate cleanup efforts and improve wastewater management along the border. The agency also said expansion work at the South Bay International Wastewater Treatment Plant was completed to help prevent additional sewage from reaching U.S. waters.
