Paris Mayor Anne Hidalgo took a swim in the Seine River on Wednesday this week in an effort to prove the “long-polluted” river was now clean enough to host swimming during this year’s Olympic Games.

Earlier this year the water showed unsafe levels of E. coli bacteria, AP reported. 

During her swim she was joined by swimmers from local clubs, Paris 2024 chief Tony Estanguet and the top government official for the Paris region, Marc Guillaume, the report says. 

Hidalgo said during the swim: “The Seine is exquisite. The water is very, very good. A little cool, but not so bad.’’

She called the day “a dream” and a “testimony that we have achieved a lot of work”. 

Estanguet added: “After twenty years of doing sports in the river, I find it admirable that we are trying to clean it up.”

In preparation for the Summer Games starting on July 26 with a grand open-air ceremony featuring an athletes’ parade on boats on the Seine, efforts are underway to highlight the river’s improved cleanliness.

As AP notes, swimming in the Seine has been banned for over a century and since 2015, organizers have invested $1.5 billion to prepare the river for the Olympics and ensure a cleaner Seine for Parisians post-Games.

This plan included building a massive underground water storage basin in central Paris, renovating sewer infrastructure, and upgrading wastewater treatment plants.

Originally planned for June, Hidalgo’s swim was delayed due to snap parliamentary elections. During that time, the hashtag “jechiedanslaSeine” (“I’m pooping in the Seine”) trended on social media as a protest against the Olympics.

Previous attempts to clean the Seine, including a pledge by former French president Jacques Chirac in 1988, were unsuccessful. Hidalgo followed French Sports Minister Amélie Oudéa-Castéra, who swam in the Seine on Saturday wearing a full-body suit.

Concerns about the Seine’s flow and pollution levels continue, leading to daily water quality tests by Eau de Paris. Early June tests showed unsafe E. coli levels, but recent results have improved.

The Seine will host several open-water swimming events during the Games, including marathon swimming and the swimming legs of the Olympic and Paralympic triathlons.