Paris has invested €1.4 billion to clean up the Seine River, but with less than two weeks until the Paris Olympics, questions remain about whether the water will be clean enough for athletes to swim in. The city has been working tirelessly to make the iconic river safe for the swimming events scheduled during the Games, which run from July 26 to August 11. Triathlon and marathon swimming are slated to take place in the Seine, but heavy rainfall can contaminate the water with bacteria-laden wastewater.
For over a century, swimming in the Seine has been illegal due to the water’s poor quality. The city has undertaken massive infrastructure projects to improve the situation, including a giant underground water storage basin designed to capture stormwater and prevent wastewater from entering the river. This basin, capable of holding the equivalent of 20 Olympic swimming pools of dirty water, is a major part of the city’s efforts to clean up the Seine for the Olympics and for Parisians in the years to come.
Despite these efforts, concerns remain. The Seine has experienced heavy rainfall in recent months, leading to unsafe levels of E. coli bacteria in the water. Paris Olympic organizers have stated that if heavy rain impacts the river’s flow during the Games, the triathlon swimming portion would be canceled and the marathon swimming competition would be moved to the Vaires-sur-Marne Nautical Stadium in the greater Paris region.
The city’s combined sewer system, which means wastewater and stormwater flow through the same pipes, contributes to the problem. During heavy or prolonged rainfall, the system can overflow, sending raw wastewater directly into the Seine. While water quality has shown improvement in recent weeks, experts warn that the situation is still delicate and could change rapidly.
The uncertainty surrounding the Seine’s cleanliness has sparked debate. French Sports Minister Amélie Oudéa-Castéra has publicly expressed confidence in the river’s safety, even diving into the Seine to prove it. Paris Mayor Anne Hidalgo has also stated her intention to swim in the Seine. However, some, like triathlete Léonie Périault, find the heightened attention surrounding the river’s cleanliness frustrating. Périault, who competed in a test event in the Seine last year, believes the water quality is comparable to other locations around the world.
Despite the optimistic outlook from officials, experts emphasize the complexity and cost of addressing the issue. Metin Duran, a professor of civil and environmental engineering, cautions that the Seine’s water quality remains a “complicated and very costly problem.” Dan Angelescu, CEO of Fluidion, a water-monitoring technology company, agrees, highlighting the fragility of the Seine’s water quality. While Angelescu has observed improvements since the new infrastructure was built, he acknowledges the difficulty in predicting future water quality, especially given the recent heavy rainfall and the short period of time the new infrastructure has been operational.
The Paris Olympics present a unique challenge for the city. Paris aims to showcase the Seine as a vibrant part of the Games, but the river’s cleanliness remains a significant concern. The coming weeks will be crucial in determining whether the Seine will be safe for the scheduled swimming events or if alternative plans will need to be implemented.
