Why this matters
Pollution in the Tijuana River has for decades impacted communities on both sides of the U.S.-Mexico border. The Trump administration has promised to fast-track solutions.
A private company may soon be using federal dollars to launch an experimental project it hopes will reduce toxic gas from the air in the polluted Tijuana River valley.
But scientists who have been carrying out years of research in the watershed are raising alarms that the technology is untested and could make matters worse.
Last month the International Boundary and Water Commission, which oversees a wastewater treatment facility along the U.S.-Mexico border, awarded Ohio-based Greenwater Services an estimated $2.5 million to test their “nanobubble technology” method to capture contaminants in the Tijuana River. The process involves pumping ozone bubbles into water. Ozone is a gas that reacts with and can break down contaminants.
The company has used the method to eliminate algal blooms in lakes and touts it as “chemical free” and “safe for humans and marine life.” However, according to the IBWC’s own project description, deploying this method on the Tijuana River has yet to be tested.
Scientists, local leaders and environmental advocates are concerned that the project has been given a greenlight by the IBWC despite a lack of data on its effectiveness or risks. They also say there has been a lack of transparency regarding the project.
Citing recent findings of a wide array of industrial pollutants in the river, and how chemicals from the river are transferred into the air, they say testing the new technology in an area adjacent to schools and neighborhoods poses public health risks.
“It’s reckless to do this in the middle of a vulnerable community,” said Kim Prather, an atmospheric chemist at Scripps Institution of Oceanography.
Prather, who recently published a study showing how chemicals in the Tijuana River are transferred into the air through aerosolization, essentially through bubbles, says adding more bubbles with ozone could cause chemical reactions, and that the list of chemicals identified in the river is still growing.
The technology has been used in wastewater treatment, Prather says, but that takes place in contained environments, whereas here, byproducts from the treatment could end up in the air.
“I can’t believe they would do that without ever having run the test,” Prather said. “They were going to just do it in the middle of the community. No one was going to know.”
Greenwater Services did not respond to inewsource’s request Monday for comment.
A spokesperson for the IBWC said the agency could not answer inewsource’s questions by this morning’s deadline.
In its project description, the IBWC says that awarding the funds to Greenwater was of “unusual and compelling urgency,” saying that should its technology be effective it could provide relief “to Americans that are exposed to dangerous levels of (hydrogen sulfide), noxious fumes and dangerous levels of fecal coliform.”
San Diego County Supervisor Paloma Aguirre said that while she supports projects that address the public health impacts of the pollution crisis in the river, solutions shouldn’t expose communities to unknown risks.
“My concern is that there’s not enough guardrails to make sure that we are not using my community as a guinea pig,” Aguirre said.
Phillip Musegaas, executive director of San Diego Coastkeeper, said he’s concerned that information about the project has been scant. Musegass said he learned about the project from Josh Cook, the Environmental Protection Agency’s Pacific Southwest administrator, who was his point of contact. After six months on the job, Cook resigned earlier this month to work with tribes on forest and watershed management, Politico reported.
Musegaas also called on the San Diego Regional Water Quality Control Board to step in to protect the public.
In response to an email from inewsource, the water regulators issued the following statement:
“Until the treatment system is deployed and the San Diego Water Board has a chance to review the data, it can’t comment on the project’s potential or efficacy.”
Water regulators added in a later email that since the project is not discharging waste, no permit is required. They said that if monitoring detects that the project contributes to more pollution, a permit will be required. They also said controlling pollution at the source and diverting the river are preferred methods to address the problem.
The board did not answer inewsource’s questions regarding Prather’s concerns that the project would be an experiment carried out in a vulnerable community.
The federal EPA also declined to answer if they would allow the project to go ahead despite the concerns and referred inewsource to the IBWC.
Type of Content
News: Based on facts, either observed and verified directly by the reporter, or reported and verified from knowledgeable sources.