A year ago, Lee Zeldin, head of the U.S. Environmental Protection Agency (EPA), visited the Tijuana River, one of the nation's most polluted rivers, and vowed to act urgently to stop the crisis.
Now, the federal agency is committing to bringing the same sense of urgency to another heavily polluted river more than 100 miles east of the San Diego-Mexico border in Imperial Valley.
“Our commitment here to you is that we’re here to do the same,” Mike Martucci, acting regional administrator for EPA's Region 9, said at a recent roundtable in Calexico. The agency and the U.S. International Boundary and Water Commission (IBWC) hosted the meeting last month to announce their latest efforts to stop the decades-long, cross-border problem.
Imperial Valley residents have long argued that past federal administrations have not prioritized solutions the way they have for other communities across the country.
For Astrid Calderas, this time feels different.
She was one of the few Calexico residents among a room filled with elected officials, government staff and Border Patrol agents who attended the roundtable. She said her neighbors didn't know about the meeting. Many of them had spent years pushing the state and federal governments for solutions.
“They’re kind of tired of the system,” she said. “They have been part of D.C. They have been part of projects. They were taken to Sacramento to speak, and nothing has happened in 10, 20, 30, 40 years. So, the people are tired. Plus, they’re very ill.”
She believes her neighbors have developed health conditions related to the pollution in the river. As an environmental health researcher, Calderas has documented hydrogen sulfide levels near the river repeatedly exceeding state standards. The toxic gas is a common byproduct of untreated wastewater, which frequently spills over the border from Mexico through the New River.
She said hydrogen sulfide has destroyed metal, such as nearby residents’ outdoor air conditioners.
“When you see them corrode, I’m like, 'Wait a minute, I live here. My community is impacted, my family is impacted,'” Calderas said.
As other families have reported experiencing, she said she believes her son’s respiratory issues, nosebleeds and eczema are related to the pollution.
“This is not only an environmental issue but a matter of public health and environmental justice and quality of life, and there has not yet been any complete solution for the community,” Calderas told federal officials at the roundtable.
The New River flows from Baja California and travels 60 miles through Imperial County into the Salton Sea. It carries a malodorous mix of partially treated sewage and waste from industrial and agricultural sectors.
News reports mention pollution in the river dating back to the 1940s.
According to the state Water Resources Control Board, the crisis “is believed to be closely aligned with population growth.”
Raw sewage from about 25,000 people was being discharged into the river from Mexicali 61 years ago. In 1975, the population rose to more than 100,000 people, according to the state board. Today, more than 1 million people live in Mexicali.
“When you hear the stories of people having gastric, esophageal and other types of cancers and the suspicion that these industrial waste have carcinogens in there, then enough is enough,” said Rep. Raul Ruiz, whose 25th District includes Calexico.
Ruiz said he had been monitoring the EPA’s response to the Tijuana River crisis.
EPA Administrator Lee Zeldin witnessed the pollution firsthand in the Tijuana River Valley, where residents there have reported symptoms related to exposure to sewage and chemicals in the river that aerosolize. After his April visit, the EPA and Mexico entered a binational agreement, called Minute 333, in December outlining a list of projects Mexico is expected to fund and build to stop cross-border contamination.
“I pressed the administrator to make that same commitment in terms of urgency and priority for the people who live in Imperial Valley, who suffer for many decades from this contamination,” said Ruiz, adding, “that it’s not just about the bigger cities and affluent communities.”
Ruiz said he got the EPA’s attention.
At the roundtable, Martucci said the federal agency is working with Mexico on expanding treatment capacity at the Las Arenitas wastewater plant in Mexicali. Its expansion would prevent more flows from entering the New River. A timeline for the work has yet to be determined, he said.
“We want to see these projects come to completion as expeditiously as possible,” Martucci said. “One of the ways that we do that is to bring pressure to Mexico to move those projects along at a pace that’s acceptable to us.”
Efforts are also underway to upgrade and expand a treatment plant in Calexico. The plant processes and cleans sewage before discharging it into the New River, which is heavily polluted by agricultural runoff, industrial waste and municipal discharge from Mexicali.
The city of Calexico is applying for Proposition 4 bonds to fund that work. Voters approved the measure in 2024 to fund urgent climate and other environmental protection projects. Nearly $50 million from the bond measure is allocated for water quality projects that could help fix pollution in the Tijuana and New Rivers. Calexico city officials said costs to expand the plant range from $10 million to $50 million.
The IBWC is also conducting a water quality study. Its findings could determine what in the water needs to be regulated in new agreements with Mexico. The agency declined to share a timeline for when it would publish the study.
In all her years of advocating for her community, Calderas said this is the first time she’s heard federal officials acknowledge they’ve fallen short.
“I’m feeling very hopeful that there’s something going to be happen(ing), especially because Dr. Ruiz was on the table,” she said.
To clean the New River, Ruiz said, is also to help the Salton Sea, which has long been contaminated by industrial waste.
“It must be the Imperial Valley’s moment,” he said.
