Seine river, Paris Photo: AFP
Heavy rain during the Paris 2024 Olympics could make events in the River Seine "difficult", says an advisor to Paris' mayor.
The Seine is scheduled to host marathon swimming, triathlon and Paratriathlon events at the Olympics and Paralympics.
Paris is hoping to improve the river's water quality, which the city claims is already suitable for bathing two days out of three on average in the summer.
However, some sporting events were cancelled in this year because of issues with the Seine's water quality.
Pauline Lavaud, the Paris mayor's advisor on energy and climate transition, water and maintenance of public spaces, said: "We're trying to reduce all risks, and if it is not possible to swim one day, the events can be postponed.
"If it rains non stop for two weeks, it could be difficult."
Swimming is set to be one of the Paris' Games major legacies thanks to a $2.5 billion regeneration project in the capital region, with three open-air swimming areas set to be made accessible from the quayside by 2025.
The fourth meet of the Open Water Swimming World Cup and the swimming leg of the World Triathlon Para Cup in Paris - both test events for the 2024 Games - were called off in August due to water quality issues.
"The amounts of rain we had, had not been [seen] since the 1970s," Lavaud said.
A rainwater storage basin is being built in Paris to significantly reduce the risks of pollution of the Seine.
The Austerlitz basin will collect rain water before evacuating it to a treatment plant, and when it has met the required health criteria, the water will be poured into the Seine.
The water will be tested every day during the Games to ensure it is safe for athletes to swim in.
"We are now back to the level of water sanitation of the pre-industrial era," Lavaud said.
"The Olympics have made us gain 10 years on our project of making the Seine possible to bathe in."
This story first appeared on the BBC