Paris shuts Seine swim spots after reopening for the first time in 100 years

A woman dives in the water as people swim at the Pont Marie safe bathing site on the Seine river in Paris, France, Saturday, July 5, 2025, during the opening of the three Seine swimming pools, as part of the 'Paris Plages' event. (AP Photo/Thomas Padilla)

Rainfall on Sunday temporarily shut down three Seine swimming sites in Paris according to the city hall website, just one day after the river reopened to bathers for the first time in a century.

Red flags flew over the three designated swimming zones in the French capital on Sunday, warning would-be bathers that the Seine was off-limits due to water quality concerns caused by the wet weather.

The closures came just a day after the river’s triumphant reopening, which capped a years-long effort to clean up the Seine, with bathers of all ages diving in for the first time since the practice was banned in 1923.

But on rainy days, the mid-19th-century Parisian sewage system often overflows, causing rain and waste waters to pour into the river.

To mitigate the risk, city officials said that the Seine would be assessed daily for the the presence of the faecal bacteria escherichia coli (E. coli) and enterococci.

Flags 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.

Another site along the Canal St-Martin in eastern Paris was set to welcome its first swimmers on Sunday but remained closed over the rain, which “compromises water quality”, according to the local town hall on X.

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.

Ahead of the Olympic Games, authorities invested approximately 1.4 billion euros (US$1.6 billion) in improving the Seine’s water quality.

Record rainfall during the Games led to the cancellation of six of the 11 competitions held on the river.

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, around 65 years after the practice was banned.