Olympic officials have dramatically postponed the men’s triathlon event due to pollution.
In worrying signs for competitors, officials say the water quality readings “are still above acceptable limits”.
Organisers have said that there has been some improvement in the water quality but they are still erring on the side of caution.
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The call to postpone the race was made at 4.15am local time just hours out from the scheduled start time of the event 8am (or 4pm AEST).
The men’s event will now directly follow the women’s race at 10.45am local time (6.45pm AEST).
The water quality of the River Seine has been an ongoing concern for Olympic officials, and things were only made worse when the rain bucketed down during the opening ceremony.
A statement from World Triathlon said Friday remains a contingency day if one or both of the races are unable to go ahead.
“Tests carried out in the Seine today revealed water quality did not provide sufficient guarantees to allow the event to be held,” read the statement.
“Despite the improvement in the water quality levels, the readings at some points of the swim course are still above the acceptable limits.”
More than one billion euros ($A1.7 billion) was spent on cleaning up the river in preparation for the Games, but organisers knew heavy rain in the days before a competition could cause the levels of the harmful bacteria E. Coli to rise.
There was hope the effects of the deluge that marred Friday’s opening ceremony would have passed in time but that has not been the case.
Britain’s Alex Yee is one of the favourites for gold in the men’s race but he must wait for his moment, while attention now switches to whether the water will be safe for the women’s race.
– With AAP