While Olympic athletes gear up to prove they’re the best in the world, Paris city officials have their own prep underway to clean up an important Olympic venue—the Seine River, which will host the swimming marathon as well as the swimming legs of the Olympic and Paralympic triathlons (but not the surfing competition—that’ll be held in Tahiti).
In the wake of reports about high levels of E. coli in the water, Paris Mayor Anne Hidalgo took a dip last week to show there’s been progress.
In late June, test results of the water were murky. A French water monitoring group revealed contamination levels to be way above safe limits determined by the World Triathlon Federation, according to the Associated Press.
“Like a lot of older cities, the pipes [in Paris] that carry sewage and storm water are the same pipes, as opposed to separate pipes in newer cities,” explains Nicole Iovine, MD, UF Health’s chief hospital epidemiologist and an infectious disease specialist. “When there’s a lot of rain, those pipes can go over capacity and then there’s runoff that ends up in the Seine or other bodies of water.”
In fact, the river has been off-limits to swimmers for the last 100 years because of high pollution levels.
France has invested $1.5 billion to upgrade the city’s sewer system and its wastewater treatment plants, and daily water quality tests have shown improvement. But bacteria levels in the river can change from day to day, Dr. Iovine says, especially after heavy rain.
That’s likely why concerns are still circulating about the Seine’s water quality as we near the Games’ opening ceremony on Friday. Here, Dr. Iovine explains why.
What happens when you swim in E. coli-infested water?
High levels of E.coli in the river can be a legitimate concern for athletes’ health. As swimmers plunge into the Seine, water will inevitably get into their eyes, ears, and mouth while they’re swimming toward gold.
If they ingest enough harmful bacteria, they could end up with diarrhea—similar to the effects of food poisoning. “That would be the most common [side effect],” Dr. Iovine says. But there’s a smaller chance of more serious consequences: “If someone has a small open wound on their skin, that could become infected from swimming in the water,” Dr. Iovine notes.
How likely is it that athletes would get sick?
The likeliness of athletes getting sick is unclear, per Dr. Iovine. That’s because levels can change on a daily basis, so risk can be higher depending on the day (and the weather).
“It’s hard to say. If there’s a super high level of contamination and they’re swimming in it, then there’s a greater chance that someone would get sick,” Dr. Iovine says. “If levels are moderate or only a little bit above what would be the threshold, that makes it a lot less likely that someone will get sick.”
The good news? “These are athletes—super healthy people who tend to be younger,” Dr. Iovine says. “All of that is in their favor and would help to make it less likely that they’d even get sick in the first place.”
You can watch the Paris Games’ open-water swimming competitions beginning August 8. NBCUniversal is the official U.S. broadcaster for the Paris 2024 Summer Olympics, but you you can also watch on Peacock, NBCOlympics.com, NBC.com, USA Network, CNBC, and E!
