Seine river Olympics: Paris mayor swims in river to prove to Olympic athletes it is clean and safe amid fears of unsafe water quality

The mayor, Anne Hidalgo, has been pictured taking a dip in the river today (Wednesday 17 July), just nine days before the Olympics are due to start in the capital. Her swim in the river comes following her promise to take a dip and it has been a promise made by Paris mayors for decades.Paris has spent over €1.4 billion since 2015 to clean up the Seine and make it safe to swim in. It will hold the opening ceremony as well as the open-water swimming and triathlon events. However, there have been continued fears over the water quality and it could yet cause the cancellation or displacement of those swimming events.

Hidalgo promised in January she would swim in the river herself before the Olympics to prove it was safe - and she has finally done it. She said: "It's bliss! We've been dreaming of this for years, we've worked very, very hard, the water is very good, a little cool but not that much”. Seven security boats were deployed for the occasion and she swam down the river for about 100 metres, switching between front crawl and breaststroke.

Officials have warned repeatedly that heavy rainstorms during the Games could cause issues with the city's sewer system, affecting the water quality of the river. Results in early June by the monitoring group Eau de Paris indicated unsafe levels of E. coli bacteria, followed by recent improvements.

On 18 June, the level of E Coli was 10 times acceptable levels and at no point did it fall below the upper limit of 1,000 colony-forming units per 100 millilitres used by the World Triathlon Federation. Organisers insist that dry weather and sunshine in July should be sufficient to make the Seine fit for the outdoor swimming events.

Organisers have previously said that the marathon swimming event could take place just outside Paris should the Seine not be suitable for competition. The Seine will host several open water swimming events during the Games, including marathon swimming at the Olympic Games and the swimming legs of the Olympic and Paralympic triathlons.