Great Stink of London (1858): The Thames and Bazalgette's Sewers

The Great Stink was the period in the hot summer of 1858 when the River Thames in central London smelled so strongly of raw sewage that it disrupted life across the capital, including the work of Parliament. The crisis broke years of political delay and led directly to Joseph Bazalgette’s intercepting sewer system, one of the great engineering projects of the Victorian age and still the backbone of London’s drainage today.

Background: a river turned into a sewer

In the first half of the nineteenth century London’s population grew from about one million to around 2.5 million. Most human waste went into cesspits, but the spread of the flushing water closet changed that. Toilets sent far more water into cesspits, which overflowed, and from the late 1840s the authorities required many houses to connect their drains to sewers instead.

Those sewers had been built to carry rainwater and ran straight into the Thames. The river, which was also a source of drinking water for many Londoners, became an open drain flowing back and forth with the tide through the middle of the city. Slaughterhouse waste, industrial effluent and the contents of overflowing graveyards added to the problem.

Cholera, a waterborne disease, struck London repeatedly: the epidemic of 1848–49 killed roughly 14,000 people in the capital and that of 1853–54 more than 10,000. In 1854 the physician John Snow traced one outbreak to a contaminated pump in Soho, the Broad Street cholera outbreak, but most experts still believed in the miasma theory, which held that disease spread through foul-smelling air.

The search for a solution

Reform was slow and fragmented. A Metropolitan Commission of Sewers was set up in 1848, and in 1855 Parliament created the Metropolitan Board of Works to coordinate drainage across the capital. Joseph Bazalgette, an engineer who had already worked for the sewer commissioners, became its chief engineer in 1856.

Bazalgette proposed a network of large intercepting sewers running parallel to the river, catching existing drains before they reached the Thames and carrying the sewage east to outfalls well downstream of the city. His plans were sent back several times in disputes with the government’s Commissioner of Works, Sir Benjamin Hall, over cost, design and where the outfalls should be. By 1858 almost nothing had been built.

The summer of 1858

June 1858 was exceptionally hot, with shade temperatures reported in the mid-30s Celsius. The low, warm river fermented, and its banks were coated with exposed sewage at low tide. Newspapers, satirical magazines such as Punch and Members of Parliament described the smell as unbearable, and the press quickly labelled the crisis “the Great Stink”.

The new Palace of Westminster stood directly on the riverbank. Officials hung curtains soaked in chloride of lime over the windows to mask the odour, and there was talk of moving parliamentary business out of London. Benjamin Disraeli, Chancellor of the Exchequer and Leader of the House of Commons, described the river as “a Stygian pool reeking with ineffable and unbearable horror”.

Because MPs feared that the foul air itself was deadly, the smell achieved what years of cholera deaths had not. Politicians who had to breathe the stench every day were now willing to act quickly.

Parliament acts

On 15 July 1858 Disraeli introduced a bill amending the Metropolis Management Act. It gave the Metropolitan Board of Works the power to plan and build the main drainage without government veto and to borrow £3 million, guaranteed by the Treasury and repaid through a local rate over 40 years. The bill passed through both Houses in about eighteen days and received royal assent on 2 August 1858.

Heavy rain later in the summer cooled the weather and the worst of the smell faded. This time, however, the political decision had already been made, and work began in 1859.

Bazalgette’s sewer system

Bazalgette’s design used gravity wherever possible. Three intercepting sewers north of the river and two south of it collected sewage from local drains and carried it eastward. Pumping stations, including Deptford, Crossness, Abbey Mills and the Western Pumping Station in Pimlico near Chelsea Bridge, lifted the flow where gravity was not enough.

The sewage was discharged untreated into the Thames at Beckton on the north bank and Crossness on the south bank, timed to go out on the ebb tide. It was not clean, but it was far from where most Londoners lived and drew their water.

On the north bank much of the low-level sewer was built inside new river walls: the Victoria Embankment, opened in 1870, which also carried a road and the tunnel of the Metropolitan District Railway, part of the underground network begun by the Metropolitan Railway in 1863. The Albert Embankment and Chelsea Embankment followed. Bazalgette deliberately made his pipes larger than his calculations required, anticipating that London would keep growing.

By the numbers

Consequences and limits

The Prince of Wales formally opened the Crossness pumping station in April 1865. The following year cholera returned to London, but the deaths were concentrated in the East End, in an area whose water company had supplied contaminated water and which was not yet connected to the new system. The pattern strengthened the case that cholera spread through water, and the 1866 epidemic was the last major one in the capital.

The system also had flaws. Untreated sewage at the outfalls fouled the lower Thames, and in 1878 the sinking of the pleasure steamer Princess Alice near the outfalls, in which roughly 600–700 people died, drew attention to the polluted water. From the late 1880s the sewage began to be treated and the solids shipped out to sea.

Bazalgette was knighted in 1875 and died in 1891. His network, expanded and modernised, still serves London. Its combined sewers, carrying both rainwater and sewage, overflow into the river during storms, a problem the Thames Tideway Tunnel, completed in the mid-2020s, was built to address.

Myths and facts

A common belief is that the stink itself caused deaths. In fact the smell was unpleasant rather than deadly; the killer was contaminated water. The irony of the episode is that politicians acted on the wrong theory, miasma, yet funded a system that largely solved the real problem by removing sewage from the water supply.

It is also sometimes said that the new sewers ended cholera at once. They did not: the 1866 outbreak came after the main drainage opened, in a district it did not yet serve.

Timeline

• 1848: Metropolitan Commission of Sewers established; cholera epidemic of 1848–49 begins.
• 1854, August–September: John Snow investigates the Broad Street cholera outbreak.
• 1855, August: Metropolis Management Act creates the Metropolitan Board of Works.
• 1856: Joseph Bazalgette appointed chief engineer of the Board.
• 1858, June: Hot weather produces the Great Stink along the Thames.
• 1858, 15 July: Disraeli introduces the bill to fund the main drainage.
• 1858, 2 August: The act receives royal assent.
• 1859: Construction of the intercepting sewers begins.
• 1865, April: Crossness pumping station formally opened.
• 1870, July: Victoria Embankment opened.

Why it matters

The Great Stink shows how a vivid, shared discomfort could push a hesitant government into funding public health infrastructure on a vast scale. Bazalgette’s sewers helped end cholera epidemics in London, became a model for cities worldwide, and still carry the capital’s waste more than 150 years later.