Just how safe is it to swim in London’s canals? We ask an expert

Picture the scene. It’s the hottest day in London’s history. You feel like you’re inside a weird apocalyptic furnace where an oven and a sauna become one cruel version of Hell on Earth. You go to the local corner shop for a Solero ice cream to cool off but the freezers are absolutely ransacked.

And then, all of a sudden, you see it in the distance: the glistening water of a London canal. It looks so cool and tempting (if you ignore the rubbish bobbing around), that it’s almost impossible to resist the urge to submerge your whole entire body into the shady depths of the water. 

But you might want to think twice before seeking that oh-so-sweet, chilly dip.

According to Tideway, more than half of Londoners think that the river Thames is safe to swim in, and 45 percent say that they would be likely to take a dip to cool off from a scorching heatwave. This week, London’s canals and basins have been filled with overheated Londoners taking the plunge to avoid the heat. Heck, east Londoners have even rebranded the north-east side of Hackney Marshes as the ‘Hackney Riviera’.

Unfortunately for us, London’s canal network is no French Riviera. The network, which includes Regent’s Canal, Limehouse Basin, Surrey Quays and the Grand Union Canal, feeds off the main River Thames. It’s consequently filled with sewage, industrial debris and all types of suspicious pollution. Swimming in London’s canals is a big NO, according to the UK’s Canal & River Trust.

Just how safe is it to swim in London’s canals? 

Watch out for the shopping trolleys

There are more than just fish roaming around in the depths of London’s canals. Some risks are obvious, but there are some hidden dangers. ‘Canals just aren’t the right places for a swim,’ says Claire Gauci, the campaign lead at the Canal & River Trust. ‘You often can’t tell how deep the water is and it could be much shallower than you think, meaning you could get seriously injured if you jump in, particularly if there are objects like shopping trolleys which you could land on,’ she says.

Disease ain’t no joke, either

‘Leptospirosis, also known as “Weil’s Disease”, can be found in canal and river water and can be fatal if not treated,’ says Claire. ‘Always wash your hands when you come into contact with canal and river water.’ 

Organisms that cause gastrointestinal illnesses are commonly found in rivers, lakes and canals, too. Don’t forget – canals are basically roads for boats: Claire warns that the water will have petrol and oil pollution. Is that summer dip still tempting you? 

It could be even more dangerous during a heatwave

‘With a really warm air temperature, the water will feel even colder and sudden immersion can bring on cold-water shock,’ says Claire. ‘The shock can make you gasp and if you’re under water, you’ll draw in water. Remember there are no lifeguards along the canals,’ she warns.

Don’t get caught up

‘Reeds and plants can also get tangled around your limbs and make it very difficult to get out,’ explains Claire. ‘The canals are for the wildlife that live in and along them, and for the boats that cruise on them. They aren’t places for swimming.’

In conclusion…

Not very safe at all. That might explain why swimming in canals is not permitted anywhere in the UK, and the Port of London Authority only allows swimming in the Thames upriver of Putney Bridge, through to Teddington.

You can still get your summer dip, though. Here are London’s best lidos, according to us. Stay cool.

The fan from Argos not cutting it? Shoreditch has new cooling wall for sweaty Londoners to chill out.

Here are the best reactions to London's heatwave so far.