SAN DIEGO (CN) – A report released this week on the cross-border sewage spill that polluted San Diego beaches reveals a breakdown in communication by Mexican officials who did not immediately inform U.S. agencies of the contamination.
At least 28 million gallons of raw sewage flowed into the Tijuana River and U.S. waters between Feb. 1 and Feb. 4, when workers repaired a broken sewer pipe in Tijuana that had collapsed Jan. 1 due to unusually heavy rains that drenched the region.
That number is much less than estimates by the U.S. Environmental and Protection Agency, which posited last month the spill may have been as much as 230 million gallons, according to a report by the International Boundary and Water Commission’s 320 Water Quality Work Group.
But the confirmed figure leaves out about 256 million gallons of sewage unaccounted for that was never pumped to Tijuana’s wastewater treatment facility in January and February, meaning millions more gallons of sewage likely contaminated coastal waters in San Diego and Tijuana.
The report states it is “difficult to determine the exact flow since it was not directly measured.”
The time frame for when the spill occurred is also different from what was reported last month. The commission’s report disputes that sewage flowed into the Tijuana River until Feb. 23.
Instead, the report says wastewater was deliberately redirected to the Tijuana River only during those four days when workers fixed the sewer pipe and lacked pumping equipment to send the sewage to the treatment plant. But the report also acknowledges “uncontrolled flows” sent wastewater into the storm drains and into the Tijuana River.
Since the North American Free Trade Agreement was signed in 1994, “wastewater treatment has improved greatly” in Tijuana but “the infrastructure in the city is aging and pipe collapses are becoming more common,” the report states.
Stormwater entered the sewer system, and sewage not only flowed into the Tijuana River but also submerged streets in the Mexican city.
Mexican officials said they did not immediately notify their U.S. counterparts of the spill because their “focus was on dealing with the broken lines” and opted to wait until the infrastructure breakdown had been fixed before informing U.S. authorities, according to the report.
Solutions suggested in the report for better resolving future spills include requiring authorities in Mexico immediately inform their U.S. counterparts of a spill when it happens, updating the plan to fix aging infrastructure in Mexico and adding infrastructure to the U.S. side to handle contaminated flows in the Tijuana River.
Imperial Beach Mayor Serge Dedina governs the southernmost beach city in California which borders Mexico and said his community is frequently affected by sewage spills that force beach closures in the working-class beach town. But this past one is the worst they’ve seen in 30 years, Dedina told Courthouse News.
He said his city has been complaining about the issue for years, and that there’s been a “consistent pattern” of sewage spills and illegal dumping in Tijuana that has polluted waters on both sides of the border.
An email by a commission foreign-affairs officer sent Wednesday afternoon states that there’s a new residential area in Tijuana not connected to the wastewater system and that samples collected from the Tijuana River in that area show elevated bacteria levels.
Dedina said that a new housing community went through the permitting and approval process in Tijuana without requiring it to be properly connected to the sewer system highlights the pervasive problem. He said while communication has improved since the latest spill, it’s also brought up major problems that have been “illegally covered up and there’s possible corruption.”
The mayor said illegal dumping compounds problems with Tijuana’s dilapidated infrastructure and that the United States cannot rely on the border city to properly treat its sewage and wastewater.
Dedina said he’s working on congressional support to build a sewage-diversion system on the U.S. side of the Tijuana River to catch and divert sewage from Mexico before it pollutes U.S. waters.
“This whole thing has really woken everybody up. This really uncovered the extent to which there’s a huge problem,” Dedina said.
“We felt completely abandoned by the agencies that are supposed to protect us and we still feel that way now. We’re working on turning our anger and outrage into action.”
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