the water quality of the Seine insufficient at the beginning of June, but improving

With a week without rain, “the weather factors are working in the right direction”, reassured Benjamin Raigneau, the director of cleanliness and water, to the press.

Less than two months before the Paris 2024 Olympic and Paralympic Games, the water of the Seine still has to prove itself. At the beginning of June, his level of concentration of fecal bacteria E.Coli, one of the two taken into account to authorize or not swimming in a natural environment, did not correspond “globally” not at the regulatory level to swim there, the Paris town hall announced on Friday June 14. At the four Parisian analysis sites (Bercy, bras Marie, Alexandre III and bras de Grenelle), this level was greater than 1,000 colony forming units (CFU)/100 ml, during measurements carried out from June 1 to 8.

If the international triathlon and open water swimming federations only authorize the holding of events on the condition of displaying a rate lower than 1,000 CFU/100ml, the Seine is getting closer and closer: between 6,000 and 8,000 CFU/100 ml at the start of the period, the values ​​decreased until reaching levels below this threshold of 1,000 on Sunday June 9.

Star of these Olympics, the Seine will host the opening ceremony as well as the triathlon, swimming-marathon and paratriathlon events.

With a week without rain, “weather factors play in the right direction”, declared Benjamin Raigneau, the capital’s director of cleanliness and water, in his explanation to journalists. The rainy spring brought “flow levels between 3 and 4 times higher than the normal flow of the Seine at the start of the summer period”he added, emphasizing that this natural factor was “the most penalizing on the analyses”.

In the event of intense precipitation, untreated water (a mixture of rain and wastewater) can be released into the river, a phenomenon that retention works inaugurated just before the Games are intended to prevent.

Plan B consists of postponing the tests for a few days, but not changing location.