PARIS — The success of the triathlon events at the Paris Olympics now depends on the hope that sunny weather and high temperatures will sufficiently improve the Seine River’s water quality. Originally planned for Tuesday, the men’s triathlon was postponed due to water contamination concerns.
Organizers are attempting to reschedule the men’s triathlon for Wednesday, coinciding with the women’s competition. However, both events will only proceed if water quality tests show acceptable levels of E. coli and other bacteria. Friday has been set as a backup date.
Forecasts predict rain and storms from Tuesday night to Thursday, which could further complicate rescheduling efforts as rain typically raises bacteria levels in the Seine.
Aurélie Merle, Paris 2024’s director of sports, explained that water samples are taken 21 and a half hours before decisions about the swim are made, leading to uncertainties about conditions on race day.
Paris has invested 1.4 billion euros ($1.5 billion) to clean the Seine in preparation for the triathlon and next week’s marathon swimming event. Despite these efforts, bacteria levels remain inconsistent, raising questions about the prioritization of aesthetic appeal over athlete safety.
“We’re living in the 21st century where, unfortunately, there are far more meteorological events that happen that are beyond the control of the organizers,” Merle stated. “We’ve seen that we go from heavy rain to extreme heat like today in very few days. So it’s actually hard to control how it can affect the quality of a river.”
Recent rains during the Olympic opening ceremony and subsequent days resulted in the cancellation of swimming portions of training events on Sunday and Monday. Although organizers were hopeful that clearer skies and warmer temperatures would improve bacteria levels, this has not guaranteed athlete safety. Ultraviolet rays from the sun can kill bacteria, but the unpredictable weather has complicated conditions.
The decision to postpone the men’s triathlon was made early Tuesday by World Triathlon, its medical team, the IOC, and city officials. Triathlete Rider shared that he learned of the delay during a 4 a.m. run, illustrating the sudden nature of the changes.
Paris Deputy Mayor Pierre Rabadan noted that “the trend is improving” but did not rule out further delays if bacteria levels remain high. Daily water quality tests measure levels of fecal bacteria E. coli, with anything beyond 900 colony-forming units per 100 milliliters considered unsafe. On Tuesday, one test site was below this threshold, while others ranged from 980 to 1,553 units.
High E. coli levels can indicate sewage contamination, with some strains posing health risks. Even a small amount of contaminated water can cause diarrhea and other illnesses.
Recently, Paris Mayor Anne Hidalgo and Paris 2024 chief Tony Estanguet took a public swim in the Seine, but data revealed that E. coli levels were slightly above the safety threshold that day.
The men’s triathlon is now scheduled to start at 10:45 a.m. Wednesday, which may increase heat-related challenges as the event concludes during the hottest part of the day. The women’s race is set to begin at 8 a.m. as planned. If the river remains unsafe for swimming, the triathlon will proceed with only the cycling and running portions.
World Triathlon president Marisol Casado emphasized the need for adaptability in competition, defending the potential format change.
Additional events planned for the Seine include the triathlon mixed relay on Monday and the women’s and men’s marathon swimming events on August 8 and 9. In the event of continued water quality issues, the marathon swimming events may be moved to the Vaires-sur-Marne Nautical Stadium, which already hosts rowing and canoeing competitions. However, shifting the triathlon swim to a different location presents significant logistical challenges due to the established cycling and running routes in Paris.
“We understand the concerns,” Merle stated. “We will continue to monitor the situation closely and adapt as necessary
