It all started on a hot summer’s day in August 2015, when hordes of people defied a 1923 law and plunged into a canal in the northeast of Paris. It was such a welcomed event that, in November, the City Hall officially proposed a plan for three swimming pools to be built along the south side of the Quai de la Loire canal basin, ready for this summer.

Paris Mayor Anne Hidalgo celebrated the plan on Twitter, writing: “City swimming: promise kept! Three pools on the Bassin de la Villette starting next July 15.” It is a bold plan that, ahem, hopefully will swim and not sink.

The Bassin de la Villette is located in the north east of Paris and is the widest part of the long and fascinating canal system that flows down into the Seine. It was inaugurated in 1808 by Napoleon Bonaparte to supply water to Parisians – they can't just drink wine you know – and was a former port area during the industrialisation of rivers. Now, it's a central cultural and recreational spot, boasting a theatre barge, boat rental, breweries and cinemas, and is a prime spot for summer wine drinking.

The temporary structures will be built into the actual Bassin, which connects the Canal de l'Ourcq with the Canal Saint-Martin. The smallest, a children's pool, will be just 40cm deep, a second will be up to 120cm deep and a third will be reserved for serious swimmers at 2m deep. The pools in total would stretch 90m end to end, and would take up 16m in width.

Liberté, Egalité, Water Qualité

Naturally, the water itself is a worry. The canal has fallen pray to a few rat infestations and, on occasion, you can watch giant rats being dredged up as you sip a fresh rosé on a canalside terrasse – but don't be put off just yet. Jean-Francois Martins, tasked with sports at the City Hall, offered reassurance to prospective Parisian bathers in Le Figaro newspaper, saying: "We've been monitoring the quality of the water in the Bassin de la Villette since 2009."

Would you jump in? Image: Pixabay

The canals were emptied and dredged under a year ago, uncovering bizarre objects hidden in their depths - from bottles to scooters to a stray toilet. Despite the occasional sight of a cupboard or some vermin, the canal is actually relatively clean and a calm hub in the bustling city, where people picnic, fish and commandeer model boats during the summer months. It is not uncommon to see overly zealous Erasmus parties dive into the canal on hot weekend evenings and there have been no reports of swimmers haemorrhaging from the mouth, eyes and internal organs after contracting Weil's disease (Google if you dare) just yet. So that’s something.

Managing the water for swimming will require stemming sewer overflow during heavy storms, illegal discharge into the water from quayside boats and barges, and agricultural run-off from farms upstream. It is doable but still a massive undertaking by the city and region of Île-de-France.

Will Paris ne regrette rien?

Is it all worth it? Perhaps. Many Parisians seem to have a thirst for outdoor swimming and will seek a cooling spot to escape the city heat again this summer – the City Hall estimates that around 1,000 people would show up to the pools on any given summer day next year. As a local and keen outdoor swimmer, a guarantee of good water quality would certainly draw me for a daily swim.

The pools will be a kind of summer pop-up, along with the annual Paris Plage which transforms the banks of the basin and Seine quayside into an urban beach every summer. This means that they will be taken down for the winter season as it is pretty unlikely that many people will want to float down a freezing canal.

Paris Plage is already a thrilling reality. Image: Wikimedia Commons

Fanatics keen for a outdoor swim in the chillier months can head to the outdoor pool at Butte aux Caille in the 13th arrondissement, which is open year-round and now heated from the warmth given off by a data centre installed in the same building.

As part of Paris' Olympic bid for 2024, the city has also been overhauling the 38 existing swimming facilities; building innovative heating systems as part of a plan to make all the pools eco-responsible by 2024.

Another new, unusual, environmentally friendly pool-heating system can be found at the Aspirant-Dunand pool in the 14th arrondissement. Water from the Paris sewers is being used to warm this pool – which has cut its electricity bill by 50 per cent. A new heat pump system was installed at the pool following tests of similar systems at the pool and several others in the Paris region. The city has 2,400km of sewers under its streets and assistant mayor Célia Blauel said that the water they contained was between 13C and 20C all year round. This heat was taken from the water and used to heat the pool and showers.

In-seine urban planning

Not willing to stop at just a canal, the ambitious City Hall has also announced that they aim to make the river Seine clean enough to swim in by 2024. The city has even suggested staging Olympic events such as the swimming triathlon in the river.

Zurich already has a perfectly good outdoor swimming spot. Image: Zurich Film Office

So, will it work? Proposals to clean up waterways are a regular occurrence in many major European cities. Berlin’s 2014 scheme included a plan to swim in a part of the river Spree, but pollution from storm water run-off and coal mining put that one on the back burners. Over in London, there is the more viable Thamesbath project. It is a partially heated twin pool rather than an open swimming area but would use river water, filtered and cleaned through tanks and aquatic plant beds. It’s reached almost £150,000 on Kickstarter but is likely to cost a fortune, so don’t hold your breath. (Sorry).

Copenhagen's harbour is now swim-friendly. Image: Thomas Rousing / Flickr

But the idea of safe and clean urban swimming for the masses does float, as there are success stories already. Both Copenhagen and Zürich have cleaned up their open waters – a harbour and a lake – making it perfectly safe to jump right in.

Paris doesn’t have many ecological factors in its favour but the city of light has a big watery dream. In spite of the odds, this project may be just about achievable, and we could one day see tourists slip in for a dip in the Seine after a visit to the Eiffel tower.

Don’t forget your swimsuit.

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