The iconic River Seine has reopened to swimmers in Paris, allowing people to take a dip in the French capital’s waterway for the first time in at least a century after a more than billion-euro cleanup project that made it suitable for Olympic competitions last year.
A few dozen people arrived ahead of the 8am (06:00 GMT) opening on Saturday at the Bras Marie zone in the city’s historic centre, diving into the water for the long-awaited moment under the watchful eyes of lifeguards wearing fluorescent yellow T-shirts and carrying whistles.
It was also a welcome respite from the scorching heat enveloping the city this week. Parisians and tourists alike, looking to cool off this summer, can dive in – weather permitting – at three bathing sites: one close to Paris’s Notre-Dame cathedral, another near the Eiffel Tower and a third in eastern Paris.
The swimming zones are equipped with changing rooms, showers and beach-style furniture, offering space for 150 to 300 swimmers.
The seasonal opening of the Seine for swimming is seen as a key legacy of the Paris 2024 Olympics, when open-water swimmers and triathletes competed in its waters, which were specially cleaned for the event.
“It’s a childhood dream to have people swimming in the Seine,” said Paris Mayor Anne Hidalgo, who visited the bras Marie site on Saturday morning.
But officials reminded swimmers of potential dangers, including strong currents, boat traffic and an average depth of 3.5 metres (11 feet).
“The Seine remains a dangerous environment,” said local official Elise Lavielle earlier this week.
To mitigate that risk, lifeguards will assess visitors’ swimming abilities before allowing independent access, while a decree issued in late June introduced fines for anyone swimming outside designated areas.
The promise to lift the swimming ban dates back to 1988, when then-mayor of Paris and future President Jacques Chirac first advocated for its reversal, about 65 years after the practice was banned in 1923.
“One of my predecessors (Chirac), then mayor of Paris, dreamed of a Seine where everyone could swim,” President Emmanuel Macron wrote on X, describing the move as the result of a “collective effort” and a moment of “pride” for France.
L’un de mes prédécesseurs, alors Maire de Paris, a rêvé d’une Seine où chacun pourrait nager. Demain sa promesse sera tenue.
C’est un héritage des Jeux olympiques et paralympiques de Paris après 100 ans d’interdiction, un travail collectif, une fierté pour le pays.
Merci… pic.twitter.com/KhymFPgIy1
— Emmanuel Macron (@EmmanuelMacron) July 4, 2025
Ahead of the Olympic Games, authorities invested approximately 1.4 billion euros ($1.6bn) to improve the Seine’s water quality.
Since then, work carried out upstream, including 2,000 new connections to the sewage system, promises even better water quality – with an unappetising catch.
On rainy days, the mid-19th-century Parisian sewage system often overflows, causing rain and wastewater to pour into the river.
Flags will inform bathers about pollution levels in the water every day, and if it rains, the sites will likely close the day after, said Paris city official Pierre Rabadan.
The presence of the faecal bacteria Escherichia coli (E coli) and enterococci in the Seine will be assessed daily using live sensors and samples.
A refuge from the hot weather
Varying weather conditions will be a critical factor. Swimmers may be in luck this year, though, with temperatures predicted to be drier than the record rainfall during the games, which had led to the cancellation of six of the 11 competitions held on the river.
With record-breaking heat hitting Europe, including France’s second warmest June since records began in 1900, authorities said they expect Parisians to embrace the relief of a refreshing swim.
Some scepticism about the water quality remains, however.
Dan Angelescu, founder and CEO of Fluidion, a Paris and Los Angeles-based water monitoring tech company, has routinely and independently tested bacterial levels in the Seine for several years. Despite being in line with current regulations, the official water-testing methodology has limitations and undercounts the bacteria, he said.
“What we see is that the water quality in the Seine is highly variable,” Angelescu said. “There are only a few days in a swimming season where I would say water quality is acceptable for swimming.”
Some Parisians are also hesitant about the idea of swimming in the Seine. The feeling is often reinforced by the water’s murky colour, floating litter and multiple tourist boats in some places.
Hidalgo, who took an inaugural swim last year, said that cleaning up the Seine for the Olympics was not the final goal but part of a broader effort to adapt the city to climate change and enhance quality of life.
The swimming spots will be open for free until August 31 at scheduled times to anyone with a minimum age of 10 or 14 years, depending on the location.
