Researchers conducting studies in the Tijuana River Valley have decided to temporarily halt their work, while several schools in San Ysidro have suspended outdoor activities after detecting elevated levels of hydrogen sulfide, a toxic gas present in sewage.

According to the International Boundary and Water Commission, between 40 to 50 million gallons of sewage-contaminated water cross from Mexico into the Tijuana River Valley daily. This flow has worsened air quality problems, causing severe discomfort for residents in southern San Diego, who are already enduring high temperatures along with the foul odors emanating from the river.

The stench has become so intense in recent weeks that, on Monday, September 9th, the South Bay School District issued a directive to move all outdoor activities indoors as a precaution. Authorities indicated that if conditions persist, this measure would remain in effect for the rest of the week.

Residents like Kevin Watson claim the odors have reached "extremely disgusting" levels, to the point where he and his family are considering moving. Others, like Ramón, have no choice but to endure the situation. “If this were happening in places like La Jolla, where wealthy people live, it would have been fixed immediately,” he told Telemundo San Diego.

In response to the growing crisis, Imperial Beach Mayor Paloma Aguirre, along with members of the Tijuana River pollution task force, have called for urgent intervention by state and county agencies. On Saturday, September 21st, southern San Diego residents have organized a march to demand immediate solutions to this problem, which is affecting both their health and quality of life.