France's Cassandre Beaugrand won gold in the women's triathlon at the Paris Olympics on Wednesday, cheered on by a delighted crowd as the hosts' gamble to hold the swim stage of the race in the Seine paid off after days of uncertainty.
The triathlon, a central showpiece of the Paris Games, started and finished at the Alexandre III bridge at the heart of the French capital, taking athletes along a section of the Champs-Elysees and past more Parisian landmarks including the Musee d'Orsay.
The men's triathlon had been scheduled to take place on Tuesday but, after the river failed water quality tests, it was postponed to 10:45 a.m. (0845 GMT) on Wednesday, immediately after the women's race.
The women began their competition at 8 a.m., just as overnight rain was easing, with the triathlon offering spectacular views as they swam in the Seine before racing their bikes and running into central Paris.
A handful of athletes crashed off their bicycles after slipping on the wet cobblestones of the Champs-Elysees.
World number one Beaugrand broke away on the last lap of the run stage and was fuelled to the finish line by ecstatic cheers from crowds lining the streets. Switzerland's Julie Derron won silver and Britain's Beth Potter took bronze.
The races going ahead will have come as a relief for teams and athletes, as well as for Paris authorities who have promised residents a swimmable Seine as a long-term legacy of the Games, with the triathlon a very public test.
"We have achieved in four years what has been impossible for a century: the Seine is swimmable," President Emmanuel Macron tweeted after the race.
The gamble that the river would be clean enough for the triathlon was never guaranteed to pay off as water quality varies widely day-to-day, with rainfall causing concentrations of infection-causing bacteria such as E. coli to rise.
"I have no doubts about the quality of the Seine, we've swum in worse water," Beaugrand said after her victory, adding that scrapping the swim and holding a duathlon -- the organisers' last resort if the river had been too dirty -- would have been "shameful" for the sport.
Wednesday's races were given the green light despite rain overnight.
Organisers make the call based on analysis of river samples taken the previous day at 5 a.m. and after discussions with experts on weather, according to Paris 2024.
Showers started again around 5:45 a.m. on Wednesday, making racing conditions more difficult for the bike stage which features some sharp turns and a quarter of the course on cobbled roads.
Fifty-five women representing 34 countries kicked off the contest at 8 a.m., with Beaugrand and Potter diving into the river side by side from a floating pontoon next to the bridge.
"The results of the latest water analyses, received at 3.20 a.m., have been assessed as compliant by World Triathlon allowing for the triathlon competitions to take place," Paris 2024 and World Triathlon said in a statement.
Paris has spent 1.4 billion euros ($1.52 billion) of public money on wastewater infrastructure to contain sewage and minimise spillage into the river, and Mayor Anne Hidalgo took a dip earlier this month in a bid to convince doubters that the water would not make them ill.