‘We’re treating the river like a toilet’: Londoners warned about taking a dip in the Thames as polls show most think it’s safe

The river is in better condition compared to the 1950s, when it was declared “biologically dead” as a result of pollution, but there are better places to cool off, writes Kate Ng

The riverbed is exposed at low tide on the foreshore of the River Thames (EPA)

Despite millions of tonnes of sewage that flows into the waters of the Thames each year, more than half of Londoners think the capital’s famous river is safe to swim in.

A poll carried out by Opinium for Tideway, the company building the Thames Tideway Tunnel under London to help clean it up, has revealed that 55 per cent of people who live in London think the river, or at least parts of it, is safe enough to swim in.

The survey also found that 45 per cent would be likely to take a dip in the river to cool off in the event of a heatwave. A fifth of the 1,000 people surveyed said they would rather swim in the Thames than a public pool because of the coronavirus pandemic.

Tideway, alongside engineer Wes Nelson, who was a former contestant on the popular reality TV show Love Island, are urging people not to swim in the Thames no matter the weather.

Most of those who participated in the survey (81 per cent) "grossly underestimated" the amount of sewage that enters the river each year, believing up to a million tonnes flow in. In reality, 39 million tonnes of sewage are still flowing into the Thames each year before work on the super sewer began.

The river is in better condition compared to the 1950s, when it was declared “biologically dead” as a result of pollution. However, the capital’s Victorian drainage system was built to serve a much smaller population and regularly overflows. This means untreated sewage spills into the Thames, said Tideway.

The super sewer being built by Tideway is a 25km-long tunnel that will “intercept, store and ultimately transfer sewage waste away from the River Thames”.

Around 16km of the tunnel has been excavated so far and the project is due to be completed in 2024.

Mr Nelson said: “Swimming in the Thames is dangerous on so many levels. It’s not just the sewage people should be aware of, but the tides, currents and water traffic too.

“The RNLI’s two busiest lifeboat stations aren’t on the coast – they’re on the Thames, rescuing people from the water in central London.”

Kayla Browne, an apprentice civil engineer at Tideway’s Carnwath Road site in Fulham, said: “If you’re considering swimming in the river, don’t do it. Think about what you put down your toilet – that is essentially what you’d be swimming in.

“It may be hard to believe but, until the tunnel is built, we’re treating the river like a toilet.

“Sewage flows directly into the Thames when it rains, as this is the only way to stop homes and streets from flooding when the existing Victorian sewers overflow.”