Poor water quality off Sentosa delays World Aquatics C’ship open water swimming event by a day

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The pontoon used for the open water venue at the World Aquatics Championships in Sentosa on July 7, 2025.

World Aquatics said in a statement that the event, which was scheduled to take place at Sentosa on July 15 has been postponed by a day.

ST PHOTO: MARK CHEONG

Follow topic:
  • The World Aquatics Championships' open water swimming start is delayed due to unacceptable water quality off Sentosa.
  • The women's 10km race is postponed to July 16 and will take place on the same day as the men's race. Other events are still scheduled as planned.
  • Water samples exceeded acceptable levels after previously meeting standards, leading to concerns for athlete health and safety.

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SINGAPORE – The start of the open water swimming competition at the World Aquatics Championships has been postponed by a day due to concerns over water quality off Sentosa, organisers announced on July 15.

The women’s 10km race, which was slated to kick off the open water programme on the morning of July 15, will now be held a day later.

A total of 69 athletes had been expected to compete in the first event of the competition.

The women’s race will now take place on the same day as the men’s 10km race on July 16.

The remaining events – the men’s and women’s 5km (July 18), 3km knock-out sprint (July 19) and the mixed 4x1,500m relay (July 20) – are set to proceed as originally scheduled.

In a statement, World Aquatics said that in coordination with the Singapore 2025 organising committee, the decision was made to postpone the women’s 10km open water swimming event “due to water quality levels exceeding acceptable thresholds”.

The postponement was announced less than eight hours before its scheduled start at 8am on July 15.

The decision followed a review involving World Aquatics, the Singapore 2025 organising committee, the World Aquatics Sports Medicine Committee, and the world body’s Open Water Swimming Technical Committee.

According to the statement, water quality testing in recent days had consistently met World Aquatics’ standards.

However, samples taken on July 13 showed levels exceeding acceptable thresholds.

In the statement, World Aquatics added: “The decision to postpone racing was made in the best interests of athlete health and safety, which remains World Aquatics and the Singapore 2025 organising committee’s top priority.”

Subsequent water samples and reviews will continue at the competition venue. World Aquatics and the Singapore 2025 organising committee will assess whether conditions are safe enough to proceed with the remaining events as scheduled.

This is not the first time water quality issues have disrupted a major international sporting event.

At the 2024 Paris Olympics, the men’s triathlon was postponed just hours before it was due to begin, after a 3.30am inspection of the River Seine revealed pollution levels too high for safe swimming.

Swimming in the Seine had been prohibited for over a century due to pollution. In the lead-up to the Olympics, the city of Paris launched a €1.4 billion (S$2.09 billion) clean-up initiative to make the river safe for competition in time for the Games.

This year’s World Aquatics Championships, hosted in Singapore for the first time, officially began on July 11 with the water polo tournament at the OCBC Aquatic Centre.

The championships feature six disciplines – swimming, diving, high diving, artistic swimming, water polo and open water swimming – and will welcome more than 2,500 athletes from over 200 countries and territories.

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