Seine awash in bacteria one month before open-water Olympic swimming

London: The River Seine – set to be a centrepiece of next month’s Paris Olympics – is still failing water quality tests one month before it is scheduled to host two swimming events.

The latest tests, completed last week and released by the Paris mayor’s office on Friday, showed levels of E.coli bacteria – an indicator of faecal matter – far above the upper limits imposed by international sports federations.

The River Seine is still failing water quality tests, one month before it is scheduled to host open-water events and the swimming leg of the triathlon.

Considered by many the most romantic river in the world, the Seine has also long had a reputation as smelly, murky, and – after busy summer nights – fringed with the filthy residue of partygoers.

The tests show that on June 18, E.coli was present 10 times above acceptable levels at the Alexandre III bridge, the planned triathlon swimming site. At no point did it fall below the upper limit of 1000 colony-forming units per 100 millilitres (cfu/ml) used by the World Triathlon Federation. The readings for enterococci bacteria were better, but they 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.

Mayor Anne Hidalgo revived the dream of swimming in the Seine when bidding for the French capital to get the 2024 Games, promising the open-water swimming competition and the swimming leg of the triathlon.

The Surfrider Foundation, an NGO focused on water quality in Europe, issued a stark warning in April that levels of E.coli and enterococci remained far too high.

French authorities have spent $US1.5 billion ($2.24 billion) in the past decade trying to clean up the river by improving the Paris sewerage system, as well as building new water treatment and storage facilities.

But major storms still overwhelm the capital’s wastewater network, parts of which date back to the 19th century, leading to discharges of untreated sewage directly into the river.

After months of unusually wet weather, the Seine is currently high up its banks, with its flow around four to five times higher than its usual summer level, according to recent readings. Organisers insist that some dry weather and sunshine in July should be sufficient to make the Seine fit for outdoor swimming events.

World Aquatics, the world governing body for swimming, has recommended that organisers of open-water events consider alternative locations to manage a drop in water quality on race day. Paris officials considered their options but ultimately decided to hope it wouldn’t rain and that the warm sun of a typical Paris summer would kill enough of the dangerous bacteria.

There is no Plan B other than postponing races for a few days to let the water flow downstream.

“We are still confident with the delivery of the competitions in the River Seine,” Paris 2024 chief organiser Tony Estanguet told reporters during a visit to the Olympic Village in northern Paris this week.

“We knew from the beginning that the plan that we decided was really aligned with good conditions at the end of July,” he said. “Now we are entering the final lap and the good zone.”

Tourist barges pass under the Alexandre III bridge.

The International Olympic Committee said in a statement to NBC News last month that the triathlon could be cancelled or turned into a duathlon – just running and cycling – if the river’s water was too polluted.

The high water levels and rain are also disrupting preparations for the opening ceremony, which is also set to take place on the river on July 26.

A rehearsal for the opening ceremony planned for Monday was postponed because the river was flowing at a level five times stronger than its normal summer reading.

The rehearsal was to have featured around 90 barges, which will be used to transport teams on their parade down the river.

Paris 2024 will be the first Olympics in history to move the opening ceremony from its traditional setting of the main Games stadium.

With agencies

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