Paris Olympics 2024: Month before Games, tests reveal river Seine unfit for swimming

The river Seine continues to fail water quality tests just one month before the Paris Olympics begin on 26 July. The river is scheduled to host the open-water swimming competition and the swimming leg of the triathlon.

The latest tests, conducted last week and released by the Paris mayor’s office, showed levels of the E.Coli bacteria – an indicator of faecal matter – are far above the upper limits allowed by sports federations.

On 18 June, the level of E.Coli was 10 times the acceptable levels and at no point did it fall below the upper limit of 1,000 colony-forming units per 100 millilitres (cfu/ml) used by the World Triathlon Federation.

The readings for enterococci bacteria were historically better, but were still at unsafe levels for several days last week.

“Water quality remains degraded because of unfavourable hydrological conditions, little sunshine, below-average seasonal temperatures and upstream pollution,” the mayor’s office said in a statement.

French authorities have spent €1.4 billion in the last decade trying to clean up the river by improving the Paris sewerage system, as well as building new water treatment and storage facilities.

But storms and extensive rain still overwhelm the capital’s waste water network, some of which dates back to the 19th century, leading to discharges of untreated sewage directly into the river.

After months of unusually extensive rain, the Seine is currently high up its banks, with its flow around four to five times higher than its usual level in the summers, according to recent readings.

Organisers insist that dry weather and sunshine in July should be sufficient to make the Seine fit for the outdoor swimming events.