Poor Seine water quality after heavy rain set to force triathletes to miss training sessions at Olympics

Olympic triathletes in Paris are set to miss their first practice session in the River Seine on Sunday because of the deteriorating water quality.

Two days of practice are scheduled before the men’s event on Tuesday, with the women’s race taking place a day later. However, organisers admit the heavy rain over the past 24 hours means the water will likely fail its next test at 4am on Sunday morning.

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A second “familarisation” – or training – event is due to take place on Monday, but organisers remain confident that the improvement in the forecast will see both races take place as scheduled.

“The rain that has fallen on Paris over the last 24 hours is likely to impact the quality of the water in the Seine over the next 24 to 36 hours,” a Paris spokesperson said. “Depending on current water quality levels and the conditions expected over the next 24 hours, it is possible that the familiarisation scheduled for Sunday 28 July at 8am may be cancelled. The decision will be taken at the daily situation meeting at 4am on 28 July.

“We are nonetheless confident in our ability to organise the events as planned from 30 July. Given the weather forecast for the next 48 hours, we expect the water quality to return to below limits within the next 24 to 36 hours.”

Swimming in the Seine has been banned for more than a century. Since 2015, organisers have invested about £1bn to prepare the Seine for the Olympics and to ensure Parisians have a cleaner river after the Games. The plan has included constructing a giant underground water storage basin in central Paris, renovating sewer infrastructure, and upgrading wastewater treatment plants.

British Triathlon’s performance director, Mike Cavendish, insisted his team were confident of doing well even if the practice session was cancelled. “While a reduction in familiarisation sessions would impact all competing nations, we have great confidence in the preparation we’ve done and know our athletes will be on the start line in the best possible shape to compete at their best,” he added.