Another study is beginning into the problems from sewage near the border in the South Bay.
San Diego County is partnering with UCSD to better understand how the Tijuana River sewage crisis is affecting people in nearby communities.
It's called an "exposure characterization study," and is part of the county's Tijuana River Valley chemical pollution impact investigation.
It's aimed at helping identify the chemicals in the air and understand how they're affecting public health.
The County says this will help them in their efforts to end the sewage crisis, something that's been affecting South Bay locals for decades.