Paris to open Seine for swimming this summer after century-long ban

One year after the Seine took centre stage at the Paris Olympic Games, hosting open water swimming and triathlon events, public swimming is set to return to the river – for the first time in more than a century.

Fulfilling a key legacy promise from the Games, the Paris authorities are to allow the public to swim in the Seine from 5 July at three points in the river, which is now deemed safe for a dip. 

Parisians will be able to take the plunge at Bras Marie in the heart of the historic centre, the Grenelle district in the west of Paris and at Bercy in the east. 

"It was an extraordinary moment [in 2024], but swimming during the Games was not an end in itself," said Paris mayor Anne Hidalgo at a press conference. "Making the Seine swimmable is first and foremost a response to the objective of adapting to climate change, but also of quality of life."

Seine swimming to return to heart of Paris after century of bans

Pollution levels

Once a favourite pastime in Paris, until last year swimming in the Seine had been off limits for a century, due to pollution levels.

Swimming will be supervised and monitored, said Pierre Rabadan, deputy mayor of Paris in charge of sports. The city expects to welcome between 150 and 300 people at any given time at the three sites, which will close for the season at the end of August. 

As on beaches, a system of flags – red, yellow and green – will signal how safe it is to swim, according to the current and the quality of the water. 

Water quality will be closely monitored, after high levels of bacteria forced the postponement of some of the competitions during the Olympics.

Checks will be carried out daily, and swimming may be suspended in the event of rain, said Marc Guillaume, the Ile-de-France region's police chief. 

He expressed "even more optimism" about water quality than last summer, given the work done to make the river cleaner. 

Olympic triathlon training cancelled again over Seine river pollution

Investment

More than €1.1 billion has been invested since 2016 to clean up the Seine: ahead of the Olympics, disinfection of the discharge from two wastewater treatment plants upstream of the capital has been reinforced.

Around 260 houseboats moored in the capital have been connected to the sewage system. 

In the neighbouring department of Val-de-Marne, 14 swimmable sites have been selected along the Marne and the Seine. Two of them will also open this year, on 28 June, at former historic swimming spots in Maisons-Alfort and Joinville-le-Pont. 

(with newswires)