Sir Joseph Bazalgette was the Victorian engineering mastermind and public health visionary behind the vast sewage system that Londoners still rely on today.
Hidden beneath the city streets lie 2,000 kilometres of brick tunnels that take raw sewage direct from our homes, along with 130 kilometres of interconnecting main sewers the size of railway tunnels. Much was engineered in the middle of the nineteenth century and includes magnificent cathedral-like sewage pumping stations.
Before Bazalgette’s designs, raw sewage seeped from inadequate sewers into the River Thames, turning it into a stinking open sewer; its foreshore thick with untreated human waste, industrial discharge and slaughterhouse effluent. The increasingly wide use of the new flushing toilets exacerbated the problem, overwhelming cesspits and causing more waste to flow into the river.
In the 19th century, London’s population numbered around 2 million. The city suffered fatal epidemics of cholera when thousands died. The Victorians had no known cure. It was widely believed breathing in ‘miasma’ – foul contaminated air – caused disease and death. London-based physician Dr John Snow put forward the theory that the disease was water-borne, but his ideas received little attention. The year 1853-54 saw cholera claim a further 10,738 victims.
In the scorching summer of 1858 temperatures averaged 35 degrees celcius. The stench from the Thames – the ‘Great Stink’ – became completely overwhelming to those nearby, including Parliament whose legislative business was disrupted.
Tons of lime was spread on the Thames foreshore and near the mouths of sewers discharging into the river to try and dissolve the toxic effluent, with little effect. Parliament was forced to hurriedly legislate to create a new unified sewage system for London. The Bill became law on 2 August 1858.
Joseph Bazalgette was chief engineer of the Metropolitan Board of Works (MBW), having began his career in public health engineering in 1849. He spent several frustrating years drawing up various plans for a revolutionary rethink of the city’s sewers, only to see them repeatedly shelved, as Parliament and others argued about the system’s merits.
The Great Stink was the catalyst for radical change. Parliament gave full responsibility for cleaning up the Thames to the MBW – favouring Bazalgette’s plans – along with the ability to borrow £3 million. This was a colossal sum then, and one which had more than doubled by the end of the project.
When completed in the mid-1870s, the new sewage network’s enclosed design – which captured both sewage and rainwater – virtually eliminated cholera. Dr John Snow’s theory about cholera being a water-borne disease was correct, although he died at the height of the Great Stink without knowing that he had been vindicated.
Integral to Bazalgette’s plans was the construction of four major pumping stations to lift sewage up from low lying sewers for discharge eastwards.
The magnificent Crossness pumping station raised the effluent from south of the river up 12 metres into a reservoir by means of four enormous powerful beam engines, designed by James Watt & Co, and named Victoria, Prince Consort, Albert Edward and Alexandra. From here it was released into the Thames well beyond London, swept out to sea on the ebbing tide.
Effluent from north of the river was pumped by Abbey Mills pumping station – another temple of engineering in elaborate Italianate Gothic style – for similar discharge into the Thames, well beyond the city limits.
Bazalgette, who remained Chief Engineer of the MBW for 33 years, also changed the face of London by reclaiming 7 kilometres of riverside land and muddy foreshore to create the vast Albert (1869), Victoria (1870) and Chelsea (1874) Embankments to accommodate his low lying sewers. He laid out new city thoroughfares, including Shaftesbury Avenue, Northumberland Avenue and Charing Cross Road, and built bridges across the Thames, including Hammersmith and Battersea.
With his sewer network hidden deep beneath the city, Joseph Bazalgette’s enlightened public health legacy is largely unsung today. This small wall-mounted bust is Bazalgette’s only public memorial.
Upgrading Sir Joseph Bazalgette’s sewer system – a 21st Century Super Sewer
London’s 150 year old sewage system is today struggling under the strain of the city’s ever increasing population – now nearly 9 million.
Millions of tons of raw sewage still spills untreated into the Thames each year, especially after extreme weather. Tideway is in the process of building a ‘super sewer’ – the Thames Tideway Tunnel – to relieve the pressure on the old system. It will run under London for 25 kilometres, from Acton in the west to Beckton in the east, at depths of between 30 and 60 metres, using gravity to transfer the waste eastwards for treatment. It is due for completion in 2024.
As part of the super sewer project, a new embankment is planned for the river by Blackfriars Bridge. The public open space will be named Bazalgette Embankment in honour of Sir Joseph Bazalgette.
Written by Nicky Hughes.