The bridge is the planned finish line for the 10-kilometer marathon swim and the aquatic portion of the Olympic and Paralympic triathlons.
But Ile-de-France precinct officials dismissed the Surfrider tests on Monday, saying the water would be swimmable for the Summer Games after key elements of a $1.5 billion plan to clean up the river are rolled out in April and May. And the city’s deputy mayor for sports and the Olympics and Paralympics, Pierre Rabadan, said in an interview Tuesday in Paris that the findings ignore a steady improvement in water quality over recent years. “I did not learn anything from the surveys they provided,” he said.
The Seine, which winds through Paris, is not historically seen as an appealing place to swim. Entering the water has been banned for a century because of health concerns, including sewage.
But cleaning it up was a marquee commitment made by Parisian authorities as part of their bid to host the 2024 Olympics.
Along with select sporting events, the river is to be the centerpiece of the Opening Ceremonies. Athletes will sail down the Seine on cruise boats with spectators lining its banks, in lieu of the traditional parade on land.
In an open letter, Surfrider said it had growing concerns about the risks to Olympic athletes if the water is still contaminated by July, calling its test results “alarming.”
The cleanup plan has faced other setbacks. In August, the Open Water Swimming World Cup, to be held in the Seine in Paris, was canceled because of low water quality after above-average rainfall. Two of four days of Olympic test events were canceled that month for the same reason.
But in a news release Monday, the Ile-de-France precinct said key structural works in its cleanup plan were yet to be put into place, including the massive new Austerlitz storm water storage basin.
It added that water treatment plant disinfection units that would be activated for the Games were not operating over the Surfrider testing period; that water quality had been degraded by heavy winter rains, which would not be a factor during the Summer Games; and that boats in the Seine, some of which release wastewater into the river, would either be connected to the city’s sanitation network by summer or displaced for the Olympics.
It said the Seine’s water will be “swimmable” in time for the summer events.
“It’s well known that the [winter] period, which is a time with a lot of rain, is not suited for swimming,” Rabadan said.
He said the city’s own measurements show that the water quality was better over the past months than in previous winters, suggesting that cleanup efforts are working. “There is really a continuous improvement in the quality of the Seine,” he said.
Rabadan added that there is no alternative venue for the Olympic and Paralympic swimming events that are expected to be held in the Seine, but that organizers may postpone some competitions by several days if the water quality is insufficient.
Plans to clean up the river have been underway since 2016, and authorities aim to open more than 20 swimmable sites to the public after the Olympics, which Rabadan said will “reconnect residents and tourists a bit more with their urban river” and “provide refreshment opportunities during the summer periods, which keep getting hotter.”
Rick Noack in Paris contributed to this report.