The concept was, and remains, a sound one — a spectacular way to ensure one of the Games' most demanding events was able to be contested through the heart of the city.
Not since 1900 has a major urban waterway been used to host swimming competitions, also in the Seine.
But rarely, if ever, has a city integrated an Olympic Games to its sights and key attractions than Paris has in 2024.
The imagination alone to envisage how the world famous landmarks could play such a vital part of the Games experience was as ambitious as any ever undertaken.
But the idea relied on Paris authorities facilitating something that has rarely been done in a city as large as Paris, cleaning a river that for over a century has been closed for swimming on account of its cleanliness.
Over 1.4 billion Euros, some $2.3 billion, has been spent to make Mayor Anne Hidalgo's vision of a swimmable Seine come closer to reality, an outlay that includes the building of a super sewer to the south of the city, and a 50,000 cubic metre-runoff tank to handle excess flow during periods of rain.
Having such an issue with pollution in a city river is not unique to the Seine.
Indeed, in March this year, rowers participating in the 169th edition of the famous Oxford vs Cambridge boat race in the River Thames were warned not to enter the Thames, with advice to cover blisters, and wear footwear when getting in and out of the boat also offered.
The BBC reported that 16 tests around Hammersmith Bridge in west London, indicated an average of 2,869 E. coli colony-forming units (CFU) per 100ml of water, almost three times the allowed limit for inland water bodies.
Rivers around the world are struggling.
Rivers are Life, an organisation based out of Louisiana State University found in a survey that 81 per cent of people considered rivers to be a vital part of the food system, 94 per cent said rivers were vital for agriculture, yet most would not eat a fish out of their local river.
If nothing else, the ongoing soap opera of whether the Seine would be fit for swimming has highlighted the issues facing so many of the world's rivers and environments in general, illustrating just how much investment is needed to return these vital waterways to health.
This reclamation of the Seine is not just important environmentally, but also to the city of Paris as a whole.
In a city where living space is at a premium and communal space highly prized, any public space has to be cherished.
The brief heatwave that cooked the city on Tuesday gave a small glimpse of how insufferable the city would be to live in if the projected impact of global warming is to carry on unchecked.
The ability to go for a dip in the shadow of the Eiffel Tower during summer would, perhaps, help avoid the annual summer exodus of the inner city for the country.
It's why Hidalgo, Paris 2024 chief Tony Estanguet and French sports minister Amelie Oudéa-Castéra all went for a swim in the weeks leading up to the Games to prove that their investment was worth it.
Then came the rain, washing out the ambitious opening ceremony and creating enormous headaches for schedulers who were forced to cancel acclimatisation swims and delay the men's race.
But on Wednesday morning, after that day's delay, the triathletes were finally allowed to take their place on the Pont du Alexander III.
That was despite more heavy overnight and early morning rain in the French capital that turned the roads slick and ensured the Seine would be flowing even more fiercely than the day prior.
The fast-flowing nature of the river was clear to all observers, the safety kayaks in the river were being forced to paddle just to stay in place, with the water streaming through the arches of the Pont des Invalides through which the swimmers would have to ride the rapids.
The swimmers, diving off the Pont Alexandre III, streaked downstream at a rapid rate of knots, before taking two hard lefts before coming back against the current, hugging the south bank where the flow was recorded at a slower rate of 0.4 metres per second.
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The adage for triathletes is always that you cannot win the race in the swim, but you sure can lose it.
Those slick roads, rife with cobbles and white painted road markings meant that many riders came a cropper, the remainder having to tip toe around the 90 degree corners.
All things considered, many of the athletes would probably have rather taken their chances with the E. coli.
Nevertheless, Flora Duffy of Bermuda, the defending champion and the Caribbean nation's only ever Olympic gold medallist, took the initiative and was the first out of the water, completing the 1,500m swim in a time of 22:05, nine seconds ahead of Italy's Bianca Seregni.
The final swimmer Ekaterina Shabalina, was more than six minutes behind in leaving the Seine's murky, fast-flowing water.
But the show was allowed to take place.
Despite the morning rain, which mercifully cleared by the time of the start, fans had crowded the course hours ahead of the race start.
The seated sections along the river were not full, but the vantage points across the bridges were, and those that did come out were treated to a magnificent display of racing.
In the end, perhaps fittingly, Duffy's bold gamble on the Seine did not quite pay off, the Bermudan getting caught on the bike and then dropped on the run — understandably given a year ago she worried she would never run again after a partial tear in her patellar tendon revealed ongoing damage.
Instead it was French favourite Cassandre Beaugrand who out fought Julie Derron and Beth Potter for the top prize in a four-way battle for the ages in the closing laps of the run.
For any sport, visibility is crucial, and there can be no more visible course in the world than through the heart of the Olympic city.
It gave exposure to a sport that, due to a myriad of different organisational bodies and specialities can, at times, feel a little scattered.
But this event was not just about the triathlon.
This was about the health of Paris's most important asset, and the difficulty of making it healthy once more.
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