Down in the dumps: Inside London's sewers

New European

05-02-2025

Below a manhole cover in east London, I stepped off the bottom rung of a ladder and the waters of a sewer splashed over my thighs. I was almost caught out by the undertow and upended in the far-from-appetising drink.
I was one of a group of Thames Water customers who had come to the company's outpost at Wick Lane to see where our money went: our money, and more besides. This subterranean excursion was part of Sewer Week, an event put on by the firm.
Down in the wet and noisome gloom, I followed my fellow visitors in single file. We were squelching through a barrel of the northern outfall sewer, built to carry rain and foul water from east London downriver to a place called Crossness, well away from the centre of the city.
Our guides were Thames Water staff known as 'flushers' – men and women who, as their title suggests, keep everything moving in the watery underworld. For a time, all you could hear was the sloshing of waders and the muffled roar of the far Niagaras of the sewer delta, and the faint sonar ping of a gas-monitoring device carried by one of the flushers.
Through history, chancers and charlatans fell over themselves to meet the water needs of the growing metropolis. In the 16th century, a German engineer persuaded the mayor to let him install a rotating water pump on London bridge: this spluttering Catherine Wheel fed gurgling wooden pipes that dribbled water into the city. In the 1800s, water companies retained scientists and other salaried apologists to praise the river water for its 'liveliness'.
So much for the water coming into our homes. As for the foul stuff travelling in the opposite direction, there is a long tradition of men known as 'gong-fermors' and rakers, who were making brass out of muck as early as the Middle Ages.
There were occupational hazards. Richard the Raker fell into a cesspit in 1326 and, according to one account, 'drowned monstrously in his own excrement'. Henry III was the first ruler since the Romans to commission public conveniences, but only people of means could afford to take their ease at one of these early privies. The common or garden citizen had to make do with the common or garden.
A Victorian cartoon entitled 'Monster Soup' showed a horrified woman looking through a microscope at a slide of tentacled nasties. Water quality had been a scandal for years, but nothing was done until 1858.
In that long, hot summer, the Thames blew the Houses of Parliament a ripe and lingering kiss. The river had become stagnant. The Great Stink of London led to the commissioning of the sewers under the direction of Sir Joseph Bazalgette, one of London's least recognised city fathers. He built or revamped an underground city comprising 1,300 miles of tunnels.
The tunnel I was sloshing through was a Bazalgette creation. After 150 years of service, Bazalgette's sewers are at last being upgraded: the Thames Tideway Tunnel, a 'super sewer' running for 15 miles east to west under the river, came online last autumn. In one 24-hour spell alone, the tunnel can remove 850,000 tonnes of sewage.
But while the engineers of Thames Water command admiration, the company's knotty financial arrangements are less impressive.
Thames Water was debt-free when it was privatised by Margaret Thatcher in 1989, but perhaps that's because we, the taxpayers, had been shouldering its outgoings. As a private company, it has borrowed heavily. A large chunk of debt was added after it was bought by an Australian bank called Macquarie. By the time they sold it again in 2017, the liability was more than £10bn.
Where has all the money gone? It certainly hasn't been used to fix the infrastructure problems. It would take more than a water diviner and his trembling hazel twig to trace Thames Water's financial problems all the way back to their source.
Stephen Smith is a journalist and broadcaster