Paris mayor Anne Hidalgo famously swam in the river to prove it was safe. Then tests showed the water contained unsafe levels of bacteria on the day she swam.
After months of delay and worry, Olympic organisers confirmed that triathlon swimming could go ahead in Paris’ famous Seine.
It comes after months of back and forth over where the river’s water quality could be fixed in time for the Paris Olympics.
Water quality tests repeatedly found unsafe levels of E.coli and other dangerous bacteria while French politicians took televised swims in the river to prove it was safe.
Paris officials frequently blame the unsafe water quality on rainfall and said they were «optimistic» the waterway would be clean in time for the Games.
But with water testing showing the opposite, how did they get the Seine ready to host the world’s best athletes?
How the Seine became unsafe for swimming
The history of swimming in the Seine stretches back more than 100 years. The river hosted swimming events during the 1900 Olympics, but bathing was then banned in 1923 due to danger from boat traffic and water pollution.
The waterway then became the city’s way to transport goods and people on boats instead.
Unsurprisingly, over time its waters became so toxic that even fish struggled to survive.
As well as being a dumping ground for broken bikes and rubbish, Paris’s main river is also polluted by untreated wastewater.
In 2015, the city announced that it would aim to clean up the river in time for the Olympics.
A comprehensive €1.4 billion clean up project slowly got under way to transform the noxious Seine waters into a swimming spot.
Some of the measures put in place to improve water quality included the construction of a giant basin to capture excess rainwater and keep wastewater from flowing into the river, renovating sewer infrastructure and upgrading wastewater treatment plants.
Politicians taking a dip and €1.4 billion spent: A timeline of the Seine’s sewage problem
2015 – Preparations begin to get the Seine clean enough for the Olympics,
June 2023 – Paris says the river will be open to the public for swimming in summer 2025
20 August 2023 – Four days of triathlon test events are scheduled in the Seine but only the first two days go ahead after water quality tests show higher than authorised levels of bacteria. “As a precautionary measure and to protect the health of the athletes, the decision has once again been taken to cancel all the swimming races scheduled for today,” organisers say. Rainfall may have contributed to the problem.
February 2024 – President Emmanuel Macron says he’ll to take a dip in the river to show it is clean enough for swimming. He adds: “I’m not going to give you the date: There’s a risk you’ll be there.»
April 2024 – NGO the Surfrider Foundation takes 14 water samples from the river on both dry and rainy days. Only one is found to be safe for swimming. They say samples included “pollution of faecal origin” and that athletes would be “taking significant risks to their health” by swimming in the Seine. The NGO blames malfunctions in the sewage network, as well as barges and riverside dwellings that aren’t connected to the wastewater networks.
The City of Paris responds to the NGO’s report by saying they were “surprised” by the timing of the report. “The Seine is not intended to accommodate swimmers from mid-September to June,” it said in a statement. For “safety reasons,” it will only be swimmable in the summer.
Marc Guillaume, the Paris regional prefect, says routine water testing would start on 1 June when new treatment facilities would be operational. During the Olympics, water will be tested at 3am each day and determine whether to hold events as planned, he says.
Olympics organisers says if pollution levels are too high, events could be rescheduled and in the worst-case scenario, the swimming section of the triathlon would be cancelled.
April 2024 – Paris Mayor Anne Hidalgo says she’ll join President Macron by taking a swim in the Seine. She says she has invited top officials to swim in the river at an event dubbed «the big dive» to be staged at the end of June or beginning of July. Macron had been invited, she confirmed, as well as Paris Olympic organisers and IOC president Thomas Bach.
«We’re going to dive into the Seine, and many volunteers have already come forward to come and dive with me and all the athletes who will be there,» Hidalgo says. «We’ll all be safe to swim in the Seine.»
May 2024 – Paris officials inaugurate a giant underground water storage basin next to the Austerlitz train station aimed at collecting excess rainwater and stopping wastewater from entering the Seine. The basin can hold the equivalent of 20 Olympic swimming pools of dirty water that will now be treated.
June 2024 – Daily water quality tests indicate unsafe levels of E. coli bacteria
2nd July 2024 – With three weeks to go before the start of the Games, an opening ceremony rehearsal on the Seine is cancelled due to dangerous concentrations of faecal bacteria found in water analyses done by Paris’ City Hall. “The quality of the water continues to deteriorate as a result of unfavourable hydrological conditions,” they say, citing “rainfall, high flow, little sunshine, temperatures below seasonal norms and pollution from upstream”.
Months of wet weather have left the river flowing at four to five times higher than its usual level. Organisers say they are hopeful that the next three weeks will bring enough dry weather and sunshine to reduce the bacteria to acceptable levels.
13 July 2024 – French sports minister Amelie Oudéa-Castéra takes a dip in the Seine. Dressed in a body suit, she dives into the river after an initial slip and swims a few metres near the Alexandre III bridge. “We held our promise,” she said.
17 July 2024 – Paris mayor Anne Hidalgo comes good on her promise and swims in the Seine. Kitted out in a wetsuit and goggles, she swims in the river while being filmed and photographed by the media.
She is joined by Paris 2024 chief Tony Estanguet and the top government official for the Paris region, Marc Guillaume, along with swimmers from local swimming clubs.
26 July 2024 – Test results show the water was not safe on the day of Hidalgo’s swim.
Tests by monitoring group Eau de Paris show that at the Bras Marie, E. coli levels were above the safe limit of 900 colony-forming units per 100 millilitres determined by European rules on 17 July, when the mayor took a dip. The site reached a value of 985.
26 July 2024 – The Olympic opening ceremony takes place on the river, with 205 delegations sailing down the Seine on boats cheered on by 300,000 spectators. Unfortunately the night is beset by almost constant rain.
27 July 2024 – At a news conference American triathlete Taylor Spivey says, “Hopefully we get to swim, bike and run because I don’t swim this much to just run and bike».
28 July 2024 – Olympics pre-race triathlon swimming scheduled for the next day is cancelled. Organisers say they removed the swimming leg of the triathlon familiarisation after a meeting about water quality among authorities tasked with carrying out tests.
29 July 2024 – The swimming portion of the triathlon training session is called off after a meeting over water quality. Event organisers say they remain optimistic athletes will be able to swim in the river when the Triathlon competition begins tomorrow.
31 July 2024 – Olympic organisers confirm the the women’s and men’s Olympic triathlon races will go ahead in the Seine. They say latest water tests showed compliance with quality standards.