Tijuana Sewage Leak Sends San Diego Near Disaster

A sudden break in a key wastewater pipe in Tijuana flooded the local river valley with raw sewage, pushing a nearby treatment plant beyond its limits and releasing toxic gas into homes overnight. The collapse of the Parallel Gravity Line, a major conduit that carries waste across Tijuana, was reported by the U. S. International Boundary and Water Commission on Friday night. The pipe’s failure caused a huge surge of untreated water to rush into the South Bay International Wastewater Treatment Plant, which is only built to handle 35 million gallons per day. For more than half the weekend, the plant received over 45 million gallons each day and even hit peaks above 60 million gallons for nine hours—well past its design capacity. The extra flow fed into the Tijuana River Channel, triggering sharp spikes in hydrogen sulfide gas. Air monitors near Berry Elementary School recorded levels of 915 parts per billion between 1 and 2 a. m. Tuesday, more than twice the federal four‑hour guideline of 360 ppb. California’s Office of Health Hazard Assessment lists a protective limit of 30 ppb for children and seniors.County health officials warned residents in the affected area to stay alert to air‑quality alerts and reduce exposure. They urged people, especially those with asthma or other lung issues, to keep rescue medications handy and use air purifiers when possible. The U. S. commission has been coordinating with Mexican authorities to repair the pipe, and Mexico says work could finish by week’s end. The commission is pushing for a faster turnaround, citing the urgency set out in last year’s binational agreement. This incident marks the second major failure of a Tijuana pipeline in recent months, following a January collapse that dumped 11. 5 million gallons of raw sewage into the river. Local leaders have labeled these events as a continuing public‑health crisis, underscoring the need for swift infrastructure upgrades. In the meantime, residents are advised to limit outdoor activity when foul odors appear, keep windows and doors shut, and use HEPA‑filtered or charcoal‑treated air purifiers to reduce indoor contamination.