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On 28 March 1819, Joseph William Bazalgette was born, known for transforming London’s sewage system and improving the health of Victorian Londoners.

As guest of honour The Prince of Wales, later King Edward VII, entered the brand new sewage pumping house at Crossness in early April 1865, its powerful engines surged into action.

The final key element in the largest civil engineering project of the nineteenth century, London’s sewer system, was up and running.

Joseph Bazalgette, as featured in Men of Mark: contemporary portraits of distinguished men, 1877.
Joseph Bazalgette, as featured in Men of Mark: contemporary portraits of distinguished men, 1877.

At the celebratory banquet, the Prince toasted the Metropolitan Board of Works, who oversaw the project, and its chief engineer and designer Joseph Bazalgette:

‘This work will be of material use to London, not so much now, perhaps, as in the future, when I hope London will become one of the healthiest cities in Europe’.

And he was right, it was not just a great feat of engineering it was a great advance for public health. Bazalgette had designed for a healthier future and through his work he arguably prevented more death and disease in this country than any other Victorian.

Initially a railway engineer, Bazalgette was employed as a surveyor in the newly created Metropolitan Commission of Sewers in 1849 before becoming its engineer three years later.

With London’s population more than doubling between 1800 and 1850, existing systems of human waste collection, removal and disposal were being overwhelmed.

Invitation to the opening of Crossness pumping station, April 1865
Invitation to the opening of Crossness pumping station, April 1865

One of the Commission’s first moves was to order the closure of domestic cesspits. Dug on open ground or beneath housing, they were the traditional means of storing human waste. Houses were instead to be connected to the existing sewers, which emptied directly into the River Thames.

Ironically, these measures were a response to the growing recognition that the health of the city, and its citizens, were in urgent need of improvement.

Britain’s first cholera outbreak had reached London in 1832, killing several thousand. It was a key event from which a momentum for such reforms emerged. Given the then prevailing belief in the miasma theory, whereby diseases were caused by foul-smelling air-born vapours, sanitary reform was viewed as particularly crucial. Unfortunately, the theory itself was nonsense.

Cholera is a water-born disease and when it struck London again in 1848, over 14,000 died. The result of actively removing waste from thousands of households had been to contaminate the Thames – the city’s main water supply.

Satirical illustration of the polluted River Thames, by George Cruikshank, London, England, 1832
Concerns about the state of Thames water are clear in this caricature from 1832, by George Cruikshank, but in the following decades it got even worse.

Miasma theory was wrong, but it was the smell, or rather the ‘stink’, of London that was the tipping point. By the mid-1800s, the Thames was an open sewer where tons of faecal matter washed back and forth on daily tides. During the hot summer of 1858 the stench was overwhelming, especially for the Thameside occupants of the Houses of Parliament.

The Great Stink’ focused the minds of politicians who sanctioned a building project on a hitherto unseen scale. The task of building a new sewer network was assigned to the Metropolitan Board of Works, the successor to the earlier Commission, and its chief engineer Joseph Balzalgette.

His solution was a system that channeled sewage and waste water through miles of tunnels into a series of main intercepting sewers. Set at a slight gradient, and assisted by pumping stations, they slowly transported it eastwards where it was ejected into sections of the Thames where it would be swept out to sea.

Engine drawings, taken from Bazalgette’s detailed plans for Abbey Mills pumping station, 1864.
Engine drawings, taken from Bazalgette’s detailed plans for Abbey Mills pumping station, 1864.

Fortunately, Bazalgette insisted on broad brick-walled tunnels rather than the narrow pipes favoured by some contemporaries. Considered as unnecessarily extravagant at the time, it allowed the system to cope with the subsequent increases in volume.

As well as making the single biggest improvement to the health of Victorian Londoners, it transformed the city above as well below ground. Long stretches of the intercepting sewers were hidden beneath vast embankments along the Thames. This reclaimed many acres of land and also changed the character of the river, which became much narrower and faster flowing.

The project progressed remarkably quickly, with much of London connected up by the end of 1865. Nevertheless, delays to allow new Underground lines to be housed in the embankments helped enable a final cholera epidemic the following year.

Bazalgette as the "Sewer Snake", in a cartoon from Punch magazine, 1883. Credit: Wellcome Collection
Bazalgette as the “Sewer Snake”, in a cartoon from Punch magazine, 1883. Credit: Wellcome Collection

Of course, tons of raw sewage were also still being dumped further down-river into the Thames – sometimes with dreadful results. The death toll from the sinking of the pleasure boat Princess Alice in 1878 would have been smaller if it hadn’t sunk close to one of the sewage outfalls. Over 600 passengers died, many poisoned rather than drowned. The horror of this event prompted the subsequent building of riverside sewage treatment plants.

Such unfortunate incidents aside, Bazalgette’s creation has served generations well over many decades. This in spite of an increasing population and the emergence of hazards he would never have foreseen – such as wet wipes and fatbergs!

While significant expansion and improvements to the system continue, the many miles of Victorian tunnels remain at the core of the system.

So let’s all raise a glass – of something drinkable – and say Happy Birthday, Joseph Bazalgette!