The organisation of the Olympic Games continues to face challenges as the French capital prepares to host the Games from 26 July 2024. As well as the well-known security concerns, there is also the issue of the poor quality of the water in the Seine.
The third Olympic Games to be held in the French capital from 26 July to 8 September (including both the Olympic and Paralympic Games) have suffered major setbacks. This time, the quality of the water in the Seine has become a cause for concern. This river is not only the setting for the impressive opening day, with a 6km ceremony and delegations sailing through the centre of Paris on special barges, but also for the open water swimming events (10km).
Although the issue is not new, it has a long history, including the cancellation of last year's Open Water World Cup due to "the water quality in the Seine being below acceptable levels for the health of the swimmers". These general tests, carried out a year before the start of the Games, did not produce the desired results. The marathon swimming competition between the Pont Alexandre III and the Pont Alma was cancelled because "the quality standards of the International Federation were clearly exceeded".
This longstanding problem persists and, despite expectations of improvement, acceptable levels have not yet been achieved. Although some progress has been made, water quality has not improved at the expected rate. Analyses carried out between 2015 and 2023, sent to AFP by Paris City Hall, show significant fluctuations last summer, with several peaks in the concentration of one of the two bacterial indicators of faecal contamination, Escherichia coli.
According to the 2006 European Bathing Water Directive, none of the 14 water sampling points in Paris reached a sufficient quality level in 2023, mainly from June to September, raising many questions about the Summer Olympics. The concentration of E. coli exceeded the maximum permitted level (900 colony-forming units/100 ml) at all points.
The same was true, although to a lesser extent, of Enterococcus faecalis, another organism that lives in the gastrointestinal tract of humans and other mammals and is considered harmful to human health and potentially life-threatening if ingested.
The latter bacteria slightly exceeded the required threshold at the Ivry Bridge (south-east) and the Garigliano Bridge (south-west): 330 CFU / 100 mL, exceeding the promising results of the summer of 2022 (sufficient levels were reached for both bacteria).
Although the results have not yet lived up to expectations, hopes remain high for the world's biggest sporting event. Five projects are underway (to be completed before the start of the Games) to increase the storage capacity of the sewerage network, thereby limiting the use of the Seine as a sewer and the pollution it causes. In addition to the cancellation of the swimming marathon, there were also problems with the triathlon and paratriathlon held in the same area from 16-20 August 2023; two days of competition were cancelled due to water contamination, this time caused by a faulty valve, according to the city council.
