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After decades of pollution and years of beach closures caused by raw sewage in the Tijuana River, San Diego County Supervisors are pursuing a local plan to divert the river and treat it directly.
They’re calling for the county to design a new treatment plant to capture and clean contaminated water before it enters San Diego communities, using potential local tax revenue to back nearly a billion dollars worth of bonds to build it.
“We need to capture all of this waste, all this pollution, and we need to treat it before it gets into our rivers, before it gets near our schools, before it gets to our beaches,” Board Chair Terra Lawson-Remer said.
The supervisors called for spending $1.8 million to design a system to divert and treat the river water. They also proposed $4 million to immediately fix a sewage hot spot on Saturn Boulevard, where river pollution becomes aerosolized. The board will vote on the plan Tuesday.
In November voters will decide whether to approve a proposed half-cent county sales tax, entitled “Protect San Diego County Health and Safety Act.” It could generate $360 million per year, with about $80 million of that earmarked yearly for Tijuana River improvements.
That annual tax revenue could fund $700 million to $1 billion in bonds needed to build sewage treatment facilities to clean the river, Lawson-Remer said. She added that local officials have used general obligation bonds for a new airport terminal, roads and other infrastructure.
“So the only real question is whether we as a community have the will and the determination to make that same kind of long-term commitment and investment to solving the Tijuana River sewage crisis?” she said.
Sewage from Tijuana flows into Imperial Beach, Coronado and other parts of southern San Diego County, sickening swimmers and surfers, forcing beach closures and threatening Navy SEALs training in Coronado.
The river also emits airborne toxins including noxious hydrogen sulfide gas, which causes asthma, headaches and other ailments in neighboring communities. And it carries industrial chemicals, pesticides and pharmaceuticals.
Wastewater treatment plants in the U.S. and Mexico filter some of the contaminants, but those facilities have failed over the past decade and released hundreds of millions of gallons of raw sewage into the river.
Recent upgrades to the plants helped reduce that pollution, and the federal government has dedicated about $650 million to repair and replace aging wastewater infrastructure.
But some of the pollution bypasses the plants and pours directly into the river. The new facility could divert and treat the river as it crosses from Mexico, supervisors said.
“We can’t control what happens across the border, but we can control what we do on our side of it,” Aguirre said.
The treatment process could involve advanced water purification, which removes nearly all contaminants using techniques such as ultrafiltration membranes, reverse osmosis, advanced oxidation, ultraviolet light and disinfection, said Natalie Mladenov, an engineering professor at San Diego State University. Or it could be treated to a lesser level, to meet the Environmental Protection Agency’s standards for discharge to the ocean.
Supervisors said it’s a chance for San Diego County to achieve a permanent solution in what they called an “aggressive timeframe.”
“We will continue to pressure Washington and Mexico, but we will set the pace,” Aguirre said. “We’re done waiting for someone else’s timeline.”
