Seine reopens to Paris swimmers after century-long ban

https://www.lemonde.fr/en/france/article/2025/07/05/seine-reopens-to-paris-swimmers-after-century-long-ban_6743058_7.html

149•divbzero•7mo ago

Comments

david927•7mo ago

Just beware of the sharks

https://en.wikipedia.org/wiki/Under_Paris

alwa•7mo ago

Oh my.

“Based on: An original idea”

I suppose so…

_zoltan_•7mo ago

it's entertainment, not science. if it fulfills that purpose then it's good. nothing else required.

david927•7mo ago

I mean, you need some plausibility to the imaginative leap. It can be crazy but as long as it doesn't disturb the audience's suspension of disbelief, you're fine, and that's a strange line.

There's nothing wrong with mocking the premise of this movie; I saw it and it deserves no defense.

dvh•7mo ago

Bull sharks are known to swim 4000km inland (even 1100km in US).

david927•7mo ago

There are around 8 to 10 major dams or weirs between the ocean and Paris.

dvh•7mo ago

They could swam before they have been built, or to paraphrase Jeff Goldblum: "Life, err, finds a way". Are you one of those people who believe dams can protect you from bull sharks? Do you know why faucets have little mesh on the outlet? That's right! Tiny bull sharks could bite your fingers when you wash your hands.

david927•7mo ago

This is so good. I'm already halfway through the screenplay for "Baby Shark". The poster will have someone dangling their finger in water in a sink and a tiny bull shark coming up to bite it.

konfusinomicon•7mo ago

this is primarily why marijuana is considered so dangerous. letting a pothead into your home will inevitably lead to them taking the aerator screens from your faucets to prevent hot ash from being inhaled during their pursuit of madness. in turn millions of minor finger injuries occur every year. spread awareness!

spauldo•7mo ago

I think you'll find that in the US they've been known to swim about 680 miles inland.

nandomrumber•7mo ago

646374.4 Smoots

https://en.wikipedia.org/wiki/Smoot

spauldo•7mo ago

They don't have to swim that far to get to Cambridge, the only place in the US where they use Smoots.

tmtvl•7mo ago

Sharks only eat like once or twice a week and are very shy creatures, so not much to worry about. You're more likely to be killed by a coconut.

david927•7mo ago

It was a joke about a silly movie premise

rossant•7mo ago

That comment might also have been a joke, ironically and intentionally missing the point that perhaps there aren’t that many sharks in the Seine.

seszett•7mo ago

Or coconuts.

kevinpet•7mo ago

One could be carried there

laxd•7mo ago

So could a shark

nandomrumber•7mo ago

Not by a Swallow

david927•7mo ago

It could grip it by the husk

jedimastert•7mo ago

> The seasonal opening of the Seine for swimming is seen as a key legacy of the Paris 2024 Olympics, when open-water swimmers and triathletes competed in its waters which were specially cleaned for the event.

Meanwhile...

> The Olympic legacy of the Seine has taken another hit, with a second athlete taken to hospital after competing in the murky waters.

https://www.thetimes.com/sport/olympics/article/second-olymp...

yread•7mo ago

It seems neither of them were clearly linked to the river? The articles on this guy were kinda clickbaity saying he "was rushed to the hospital" when he tweeted that he rushed to the hospital because of the stomach bug

thaumasiotes•7mo ago

Since the reason for not swimming in the Seine was sewage, a "stomach bug" is exactly the problem you'd expect to develop after swimming in it. To rule the water out, you'd need evidence that, say, the guy ate at a restaurant with several other people who didn't go swimming, and they got sick too.

mym1990•7mo ago

Why not just compare the incidence of sickness at the swimming event vs other triathlon swimming events and see if 2(or whatever the number of competitors affected was) is abnormal and work from there?

pdabbadabba•7mo ago

Yep. That has, in fact, been done and seems to show an elevated risk of GI illness in Olympians who swam in the Seine compared to previous Olympics.

https://www.medpagetoday.com/special-reports/exclusives/1116...

thaumasiotes•7mo ago

That would be an approach to the question of "is the Seine dirtier than other triathlon events?", but it wouldn't address the question of "how did this guy get sick?"

bluGill•7mo ago

i cannot find current data, but france had more food poinoning case than the us about 20 years ago (that is not per capita, that is total) thus it something they ate is not unlikely

layer8•7mo ago

Meanwhile:

> Paris officials say they have taken several measures to ensure swimmers can safely enjoy the long-anticipated reopening, including daily water pollution testing and implementing a swim test for bathers. The water quality is "exceptional", said Marc Guillaume, the prefect for the Ile-de-France region that includes Paris. "We are monitoring two bacteria, E. coli and enterococci, and for one we are ten times below the thresholds and for the other more than 25 times below," he said.

_zoltan_•7mo ago

let him swim in it. that's the real test. if the official claims it's exceptional then surely it's not a problem for him.

padenot•7mo ago

He did last year, alongside mayor Hidalgo and others, such as Tony Estanguet, who is a former athlete and was overseeing the olympics and the minister for sports.

Article in French: https://www.franceinfo.fr/les-jeux-olympiques/paris-2024/bai...

ameliaquining•7mo ago

Amusingly, President Macron also said that he was going to swim in it to prove it was safe, but ultimately didn't. According to Wikipedia, "the primary reason cited was the concurrent French general election, but reports also circulated that protestors had planned a mass defecation event to coincide with the swim."

bambax•7mo ago

People living in houseboats along the river have been swimming in the Seine forever. And every summer, young people, possibly a little drunk, jump into the water as a dare from bridges near Notre-Dame.

But yes, this is more mainstream and open to all so it's kind of big news.

wdavidw•7mo ago

I live on a houseboat just after paris in Meudon, facing Boulogne, we go paddle and swiming with the kids since they are 5 years old. The thing is to avoid going to the river the days after big rains. It is a very pleasant area along the Saint Germain Island (bras mort de l’Île Saint Germain)

forty•7mo ago

The news is that it's now allowed / legal

cladopa•7mo ago

when I was a kid, I swam in the Seine one day out of young stupidity and the next day I got hives on my skin and it was very itchy. I learned the lesson and luckily in a couple of days I was back to normal. Some of the people in my group(that swam with me) had longer lasting problems.

liotier•7mo ago

> and every summer, young people, possibly a little drunk, jump into the water as a dare from bridges near Notre-Dame

After ending high school exams in 1993, we jumped into the Seine from Pont de Neuilly. I suppose this sort of antics have been going on since times immemorial and without counting bacteria beforehand... But I'm glad the river has cleaned up !

My first impression upon hitting the water: 1 - it is actually water (I expected mud !), 2 - wow, there is actually current and the shore goes by rather fast... No problems of any sort.

Anyway, it is fun - do it, and have a spotter to check for ships !

nextos•7mo ago

One of the benefits of EU regulations is that they have brought some order to the dumping of raw sewage into rivers and seas. But there is still a lot of work to do.

Local authorities from lots of EU regions generally avoid measuring water quality after rainy days because raw sewage is still often dumped under those conditions.

Even in Basel, where the Rheine is really clean, authorities sometimes advise not to swim.

noughtme•7mo ago

The source of the Seine is in Burgundy. Not a European, so wondering what the relationship between the Seine and EU regulations is.

vasco•7mo ago

The seine, burgundy and paris are all part of EU.

maeln•7mo ago

An important part of the pollution in the Seine is from Paris itself. Due to being an old city, the sewer system and the flood water system (i.e rain) goes through mostly the same tubes and are dump directly in the Seine. This leads to the river being full of biological contaminent, a.k.a, shit.

A lot of effort was done to remediate this very old issue, with a very big push before the Olympics games (but improvement to the sewage system has been going on for years).

p1necone•7mo ago

Turns out you can dump raw sewage in rivers at any point along them, not just the source.

Also Burgundy is just another part of France which is in the EU, so not really sure what you mean.

thinkingtoilet•7mo ago

Are there other options when it rains? I imagine they're not dumping sewage into rivers for fun.

joskvw•7mo ago

Dedicated stormwater infrastructure separate from sewage pipes solves the problem. You can also build tanks to hold overflow.

ericvsmith•7mo ago

In DC, they're storing the combined runoff+sewage until it can be treated: https://dcist.com/story/23/09/18/new-anacostia-river-tunnel-...

As expensive as this project is, separating the storm drains from the sewage lines (https://en.wikipedia.org/wiki/Combined_sewer) in an existing system is much more costly.

zrail•7mo ago

Portland, Oregon completed a project in 2011 that successfully eliminated almost all of the combined sewer overflows into the Willamette river and Columbia Slough (a swampy area on the south side of the Columbia river near the airport).

There was a ton of work done to reduce the amount of water ending up in the sewer during storms followed by some large infrastructure improvements to improve the carrying capacity of the sewer itself.

https://www.portland.gov/bes/about-big-pipe

alexey-salmin•7mo ago

Not mixing sewers and rainwater drains is the usual choice.

lsllc•7mo ago

In London the Thames Tideway Tunnel is designed to intercept and divert sewage overflows from the River Thames, particularly during heavy rainfall:

https://www.bbc.com/news/science-environment-68464798

I think there's a B1M episode on Youtube that has a good overview.

ashoeafoot•7mo ago

The uk escaped this madness, here a entrepeneur can still take a free market bath as god intended. https://www.sewagemap.co.uk/

ourmandave•7mo ago

Pfft, raw sewage? Amateur hour.

Back in my day we'd have river fires that burned 50' high and burn bridges.

https://case.edu/ech/articles/c/cuyahoga-river-fire

cm2187•7mo ago

The water is "so clean" that you have mandatory showers before going in... But it's France, so how would you live without pointless regulations?

jt2190•7mo ago

People wear all sorts of oils and perfumes and deodorants that should be washed off before swimming.

_zoltan_•7mo ago

it's a river. Couple hundred people swimming in it with deodorants is meaningless.

loloquwowndueo•7mo ago

Maybe that was the initial thought? It’s a river, a handful of homes emptying sewage there is meaningless. And centuries later, here we are.

baud147258•7mo ago

I'd say it's the same rules as any other (swimmable) river in France, from the big to the small. Maybe it'd make more sense just for smaller rivers, but where do you draw the line? Like it's easier and simpler to just use the same set of rules

alamortsubite•7mo ago

This is true, but shortsighted. The overall Paris-Plage plan is a resounding success. Re-opening the Seine to swimming is likely to be just as popular.

cdrini•7mo ago

I was dubious so did a fact check, and it is indeed necessary! Not sure what the reasoning is, I wonder if it's some rule about public swimming which was originally created only for pools? Or maybe there are some wildlife concerns with certain lotions/etc getting in the water.

> Y a-t-il des douches ? > > Oui ! Chaque site de baignade propose des douches – obligatoires avant d’aller se baigner –, un accès à des toilettes, un poste de secours ainsi que des espaces pour s’asseoir et profiter du soleil.

https://www.paris.fr/pages/baignade-en-seine-toutes-les-ques...

ameliaquining•7mo ago

Maybe they're just erring on the side of caution since they just cleaned the place up.

alexey-salmin•7mo ago

I won't be surprised if the shower drains back into the river.

alamortsubite•7mo ago

My guess is while there are few people swimming in the river now, it's easy to imagine there will be tens of thousands in a couple years. Paris-Plages is a huge hit. The city probably figures it's better to ease people into the habit rather than try to force it on everyone afterward.

seszett•7mo ago

Isn't a shower before swimming in a public pool a universal thing? It's always required in France.

cm2187•7mo ago

A swimming pool isn't a gigantic body of moving water that is already barely clean enough to be swimming in it in the first place.

spauldo•7mo ago

I thought running through the shower area between the changing room and the pool and trying to avoid the cold water as much as possible was the norm, but maybe it's different in France.

bigstrat2003•7mo ago

I haven't been to a public pool in ages, but growing up in a small US town I can't say I remember any of the kids at the community center taking a shower before using the pool. It may be different now, but I would be disinclined to say a shower is universal at least based on my experience.

ameliaquining•7mo ago

I also grew up in a small U.S. town, and the posted rules said you had to do this, but I don't think they were consistently followed or enforced.

refurb•7mo ago

It’s pretty standard now.

But not so much for hygiene standards (the chlorine takes care of that), but more for maintenance issues.

Rinsing off before going in reduces the organic load in the pool, which reduces the amount of chlorine consumed, which reduces the amount of chemicals needed to maintain clean water (not to mention reduces chloramine levels which can irritate swimmers lungs).

Epa095•7mo ago

I am staying at a north American hotel with a pool now, and I have noticed that absolutely nobody showers before (and they come with dry hair), despite the sign asking them to do so. I have been wondering if this is a cultural difference between Europe and America.

It's absolutely disgusting.

refurb•7mo ago

Yes, but pools aren’t natural bodies of water that already don’t meet sanitary standards, not to mention the water is constantly moving so it’s not like the water is worse when someone goes in later.

rixed•7mo ago

I wonder if the water from those showers is drained directly in the river ?

cycomanic•7mo ago

For anyone visiting Paris, the sewer museum is definitely a unique experience and worth a visit (although smelly). It gives you a grasp of what a monumental it was to build the sewers back then. You can also see the overflow reservoirs that dump water into the Seine when there is heavy rain (they were talking about the cleanup efforts leading to the Olympics when I was there some years ago).

sidibe•7mo ago

+1, I always recommend this. It's interesting, doesn't take very long, and well situated right in the middle of the tourism to get a little break from whatever the outside weather is.

ourmandave•7mo ago

I wonder what comes up when you search for "restaurants in your area" coming out of there. Or why someone actually would.

alamortsubite•7mo ago

Absolutely, and if you like the Musée des Égouts de Paris, you'll also enjoy the sewer museum in Brussels.

fouronnes3•7mo ago

I'm going to swim a 1000m race [0] there tomorrow morning! Wish me luck HN!

[0] https://openswimstars.com/paris/

darekkay•7mo ago

Bonne chance!

wartijn_•7mo ago

Good luck!

IgorPartola•7mo ago

Удачи!

fouronnes3•7mo ago

well, race is cancelled due to weather :(

avidphantasm•7mo ago

You know that river was bad if they closed it in 1925.

saltysaltysalty•7mo ago

Commendable they’ve been able to remove the organic toxins, but I’m left wondering about PFAS, pesticides, microplastics etc?

greatgib•7mo ago

Already closed the day after (today) because of bad quality following a very light rain...

This is a political marketing stunt, not to be believed except for idiots that would really go to swim in this disgusting water not knowing about the consequences on themselves that they could expect...

Look at what happened to some swimmer athletes during the Olympic games...

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Seine reopens to Paris swimmers after century-long ban

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