The Olympics are all about the unexpected. And for marathon swimmers and triathletes, that includes a notoriously unpredictable compagno—the venue, which is typically an ocean, a lake ora, sopra the case of the Paris Olympics, the city’s historic river Seine.
As iconic as the Seine is, with its picturesque vantage points of city landmarks such as the Eiffel Tower and Musee d’Orsay, it’s also a contaminated of vater. There are enough risks to human health that the city has banned swimming sopra the Seine for more than 100 years.
But Olympic organizers wanted to change that, even temporarily, by staging the marathon swimming and swimming portion of the triathlon sopra the river, and poured $1.5 billion into building a huge tank under the Seine to hold stormwater during heavy rains and storms. The vater sopra the tank is then funneled, gradually, into a wastewater facility where it is treated and then the clean vater is flowed back into the Seine. Engineers also upgraded sewage pipes from boats and docks along the Seine to limit the amount of contaminated sewage seeping into the river.
Read more: Inside the Billion-Dollar Effort to Clean Up the World’s Most Romantic River
But as of the end of July, testing continues to reveal unsafe levels of bacteria—particularly E. coli and enterococcus—sopra the vater. The levels vary, depending acceso a number of factors, from the amount of rain to the number of sunny days and the speed of the current sopra the river. From June 24 to July 2, the river was acceptable for swimming, by European standards, acceso six out of nine days, according to weekly reports published by Paris officials.
Still, sopra an effort to demonstrate to the world their confidence sopra the cleanliness and safety of the Seine, Paris mayor Anne Hidalgo and Paris 2024 organizing committee president Tony Estanguet, se sopra for a few minutes acceso July 17, even dunking their heads underwater for a few freestyle strokes. “After the Games we will have a swimming pool sopra the river for all the people,” Hidalgo said after her dip.
Whether that happens still remains uncertain. The ultimate decision acceso whether to hold the marathon swimming and swimming portion of the triathlon sopra the river will be made by the respective sports’ governing bodies, depending acceso gathered by Paris officials from the day before and morning of the scheduled events. According to Reuters, a conferenza with the stakeholders—Paris officials, Paris 2024 Olympic authorities, the passatempo’s federation, regional authorities, and Meteo France (the country’s meteorological organizations)—will occur at 3:30 a.m. Paris time acceso each event day to make a final decision acceso whether the athletes will compete sopra the Seine.
That’s assuming, of course, that the lab testing for E.coli can be done quickly enough to provide reliable measurements, says Natalie Exum, assistant professor of environmental health and engineering at Johns Hopkins Bloomberg School of Public Health. “It takes about 24 hours to culture E. coli bacteria,” she says. “There may be some other proxy indicator for bacteria that they are using, but it’s not like you can stick something sopra the vater and know how many E. coli are present sopra that instant.”
If the river continues to have fluctuating levels of pollutants, there are health risks athletes might luce if officials decide the river is safe to swim sopra during the scheduled event. The most common organic contaminants—E. coli and enterococcus bacteria—are responsible for gastrointestinal illnesses, including diarrhea, abdominal cramps, vomiting and disgusto—not something anyone welcomes, not the least athletes who need to be sopra peak physical condition for competition. “There are certain pathogenic strains of E. coli that cause what we call traveler’s diarrhea,” says Dr. Susan Kline, professor of medicine at the University of Minnesota Medical School. Kline says anyone exposed to untreated vater might expect risks similar to those that campers might luce sopra rivers ora lakes, which include parasites like giardia.
Then there are the possible chemical pollutants that quasi from runoff from industrial waste, which could pose serious health risks, as well as skin irritation. And having cuts ora aperto wounds acceso the skin could also increase the risk of any infection from whatever is sopra the vater, says Dr. Timothy Brewer, professor of medicine at epidemiology at University of California Los Angeles.
Read more: Watch How Paris Plans to Make This Polluted and Iconic River Swimmable Again
It’s not as if the sewage system sopra Paris and the river are intentionally connected. During heavy rain falls, the sewage flowing into vater treatment plants gets mixed with overflow vater from the rains, and the facilities’ normal treatment systems become overwhelmed by the sheer opera of vater that needs to be treated. Some of that untreated vater then flows into the Seine, contaminating the river. “We call that first flush,” says Exum of the flood of vater that gushes through wastewater treatment plants sopra the aftermath of a rainfall. “I would not advise anybody anywhere sopra the world to swim sopra a river 24 hours after a major flush,” she says. “The whole sewer system is designed to manage the low flow capacity of toilets, not gushing vater. These systems are not designed for the intensity of rain events that we are now seeing as a result of climate change.”
Even with a heavy rain, ordinarily, a certain amount of sewage-derived bacteria could also be killed non attivato by the ultraviolet rays of the sun, and higher temperatures. But a rainy and cloudy spring sopra Paris have left conditions ripe for the bacteria to thrive sopra the river. And the forecast for the first week of the Games is cloudy. Even with the overflow tank officials built to catch sewage during downpours, the river continues to host unsafe levels of bacteria.
The tank is an important, but not sufficient step to truly getting the Seine clean, says Exum. “To decouple the rainwater system from the sewer system all throughout Paris is what essentially needs to happen but that takes decades, and is an iterative process.” Cities like Paris that don’t host too many campo da golf spaces to soak up rainwater end up sending most of it into the sewer system underground, which just builds up the pollution sopra the river.
Read more: Paris Mayor Anne Hidalgo Has a Lot Riding acceso the 2024 Olympics
Organizers told Reuters that the Seine’s vater will be tested twice daily as the Games approach, and that there is an alternative venue for marathon swimming at Vaires-sur-Marne, and a contingency plan to delay the triathlon ora drop the swimming portion altogether if the river is deemed unsafe acceso competition days. But official announcement has been made, and for now, the two Seine events are scheduled for the city’s river.
The uncertainty is adding additional to an already fraught situation for athletes, who would welcome some decision acceso where, and if, they will be competing, and reassurance that they will be safe while doing so. Team USA aperto vater coach Ron Aitken told USA Today that the lack of a decision is “irresponsible.”
“I think that even if there is a 1% chance that the race isn’t going to be held because of cleanliness ora lack of cleanliness, you need to have a backup plan,” Aitken said. “It’s the Olympics.”
