“We had our test event there and I must say we haven’t had any problem,” Rolland told the BBC at the end of a day’s programme watched by, among others, the International Olympic Committee (IOC) President Thomas Bach.

“Of course we were lucky with the weather conditions at that time, and we know the water is polluted.

“But it’s still safe for the rowers.

“Our first priority must be the health of our athletes, who we know train so very hard.

“We want to deliver the best conditions for them to perform.

“We have had some difficulties and issues to address.

“But we are working with the Rio 2016 Organising Committee, the Brazilian authorities and the IOC to make sure we can address these issues.

“We don’t make measurements on the River Thames, but if we did so, you will not want to drink or swim there.

“We have to be transparent, but at the same time we have to make sure we don’t exaggerate.”

In June, World Rowing published a comprehensive report into the quality of the water at the 2016 rowing venue of the Rodrigo de Freitas lake following a wave of reports of pollution by sewage and, in April, by 50 tonnes of rotting fish carcasses.

The report concluded that the venue would be safe for competition, although it recommended a number of best practices.

“Based on these actions of the Rio health authorities and the recommendations above, regular reviews of statistics on water quality with experts and the regular testing of the water quality by the state and city authorities, the FISA Executive Committee has accepted the data provided which indicates the athletes will not have increased health risk through incidental water contact by competing at the Lagoa,” the report said.

“The FISA Executive Committee continues to monitor the situation.”

At the Olympic trial event last month - the World Junior Championships - a number of rowers fell ill with stomach complaints after racing on the Lagoa, including 15 members of the US team.

But the IOC have insisted that these instances of illness were not directly related to activity on the lake, because a coach who had not been on the water was also ill while an athlete who capsized was not.

Rolland also said sprint racing over 500 metres could form a part of the sport’s Olympic future - but stressed that it must remain as an endurance event over the traditional 2,000 metres.

The Olympic gold medallist in the men’s pair at the 2000 Sydney Games accepted the idea that racing over shorter distances could help add to the appeal of the sport as it looked to adapt to the new vision adopted within Bach’s Agenda 2020 reform process.

“Why not?” Rolland said.

“We have to renew ourselves as an Olympic sport, and we can work on different dimensions.

“We want to develop rowing of all different kinds including coastal rowing and shorter distance sprints.

“But for the Olympics we want to remain an endurance sport above all.

“We have to be very cautious.

“To improve one dimension we don’t need a revolution, we don’t want a revolution.”

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