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Lee Tunnel - BBC Super Sewer series - Tom Swingler (Raw TV Ltd)

The Five Billion Pound Super Sewer

Following workers for three years as they race to build an enormous super sewer on time and on budget.

About the series

The super sewer is the largest upgrade to the sewage system for more than 150 years; built 90 metres under London, it’s also the biggest engineering challenge for a generation. In this major new three-part series, The Five Billion Pound Super Sewer puts cameras at the heart of the action, following workers across the capital for the past three years as they race to build the enormous tunnel on time and on budget. 

Here, you can read about the original Victorian sewer system, or about unfreezing urban infrastructure. For more about the series, you can head to the BBC programme page.

Discover the range of qualifications and modules from the OU related to this programme:

A worker in an orange coat and white hard hat smiles into the camera. We can see he is in a gigantic tunnel

Copyright: Tom Swingler (Raw TV Ltd)

Aerial photo of the Thames in London, focusing on cranes stationed on the water. Tall buildings of the city are in the distance

How London got its Victorian sewers

Recently, there has been a major upgrade to London’s sewer network. But how did the existing system come into existence?

1858 – A city in crisis under Creative Commons BY-ND 4.0 license

The first two weeks of June 1858 were exceptionally hot. That weather led to desperate politicians voting a bill for a complete new sewage system for London through both Houses of Parliament in only 18 days. By 2 August they had approved an Act of Parliament for the expenditure of £2.5 million (about £300 million in today’s money) – and it was to be publicly financed.

Why were they so desperate?

The answer was the threat of water-borne disease and nowhere was this more urgent than in the brand new Houses of Parliament.

London was a rapidly growing city with a population that had reached two million by 1840, having doubled since the beginning of the century and it had a big sewage problem. Before the construction of proper sewers, most of London’s sewage was recycled as fertilizer. Individual houses had cesspools (though often these were just the cellars). The solid waste or ‘night-soil’ was collected from these by well-paid ‘nightmen’ (they were only allowed to work at night) who transported it to the market gardens surrounding the city. The wastewater either seeped into the ground or flowed through the streets into the old natural rivers, which had become public sewers. These all eventually flowed out into the River Thames.

London’s water supply problem

Supplying clean drinking water was another serious problem. Some of London’s water came from shallow wells within the city and was delivered by the bucketful. More prosperous areas had piped water provided by private water companies from springs in the hills around London or, most dangerously, from the Thames itself.

The invention of the flush toilet or water closet at the end of the eighteenth century made things worse. Well-off households that could afford a proper water supply could now dispense with a smelly cesspool and simply flush all their waste away – and out into the Thames.

Cholera arrives

A drop of Thames water - Punch magazine

A drop of Thames water - Punch magazine

Cholera is a deadly disease. The primary symptom is acute diarrhoea, which drains the body of nutrients and fluids. In 1831, there was a global outbreak. It had originated in India but had spread across Europe and arrived in Britain. This outbreak killed over 6000 people in London. At the time, the cause of the disease was a mystery. 

The link between the disease and the contamination of drinking water by human sewage was suspected by some. It was obvious that Thames water, when seen through a microscope, was far from clean and it was a subject of wonderful campaigning cartoons in the London newspapers and the satirical magazine Punch.

However, at this time the dominant opinion was the 'miasmatic theory', that the disease was spread by 'fould air'. It wasn't the polluted water that was deadly, but the very smell of it.

Would the Houses of Parliament have to be abandoned?

G.W. Wilson & Co., photographer, Public domain, via Wikimedia Commons

Nowhere was this problem more urgent than in the brand new Houses of Parliament.

Construction had started in 1840 following a disastrous fire which had destroyed most of the old Palace of Westminster in 1834. The lavish new building was initially estimated to cost about £700,000 but ended up costing three times as much. By the summer of 1858, the building was almost complete (and the money spent). 

Joseph Bazalgette reviews the options

Joseph Bazalgette, Civil Engineer

Joseph Bazalgette

There was no shortage of ‘solutions’. In 1848 the government had established a Metropolitan Commission of Sewers. After issuing a general invitation to engineers to submit proposals for dealing with London’s sewage, an engineer with a background in land drainage methods, Joseph Bazalgette, was hired.
In 1855, the Metropolitan Local Management Bill was put through Parliament. This attempted to centralise some aspects of the administration of London. It created the Metropolitan Board of Works, one of whose duties was to ‘make such sewers and works as they may think necessary for preventing all and any part of the sewage of the Metropolis from flowing into the River Thames in or near the Metropolis'.

Joseph Bazalgette was appointed chief engineer for the Board of Works. He took his duties very seriously, reviewing 137 different proposals and producing a detailed plan for a scheme of intercepting sewers collecting London’s sewage and discharging it into the Thames 10 miles further downstream (which could be interpreted as being ‘near the Metropolis’). 

The ‘Great Stink’ forces action

The weather of the first two weeks of June 1858 was exceptionally warm, and the River Thames was extremely smelly. Nowhere was it more unpleasant than in the Houses of Parliament. Sheets soaked in disinfectant were hung up to disguise the smell, but it was increasingly obvious that something serious would have to be done. Otherwise Parliament would have to relocate upstream (and out of London).

The ‘force of sheer stench’ (as the Times newspaper put it) prompted the government to act. On 15 July Benjamin Disraeli, as Leader of the House of Commons, introduced a new bill in Parliament, the Metropolis Local Management Amendment Bill. 

One key element was to reword the 1855 Act so that the sewage system would be for ‘preventing as far as may be practicable, the sewage of the Metropolis from passing into the River Thames within the Metropolis’. These extra words, ‘as far as may be practicable’ immediately allowed Bazalgette's proposed scheme to be used. 

The bill was debated for three days and became law on August 2nd. Only 18 days after the bill had been introduced and two months after the ‘Great Stink’ the required Act of Parliament was put in place for Bazalgette to start work.

Bazalgette’s engineering masterpiece

A map of Bazalgette's 1858 scheme

Bazalgette’s scheme was an extraordinary feat of engineering. It involved the construction of major new ‘intercepting sewers’ that would collect sewage from the existing piecemeal array of sewers and move it down river. On the north bank, sewage would be carried eastwards as far as Beckton, eight miles east of St Paul's Cathedral, to be stored and then discharged on the outgoing tide. On the south bank, the sewage would flow as far as Crossness, two miles further downstream, where the same would happen. 

sarahtarno under Creative Commons BY-NC-ND 4.0 license

Most of the scheme was very carefully designed to flow by gravity, but at critical points, all of the sewage would have to be pumped to a higher level using huge steam pumps. Those installed at Deptford in 1864 were at the time the largest ever built.

One of these pumping stations was at Abbey Mills, where much of the sewage from London’s East End had to be pumped up into the enormous Northern Outfall Sewer which flowed across the marshland towards the discharge point at Beckton. This was a prestige project and the buildings above ground, such as the pumping stations, were lavishly decorated.

Philip Halling, Creative Commons Attribution-Share Alike 2.0

Bazalgette replaced 165 miles of old sewers as well as constructing 1100 miles of new ones. It required the excavation of 3.5 million cubic yards of earth by hand – there were no mechanical diggers at the time. The construction consumed 318 million bricks and demand was such that it forced up the price of them in London by about 50%. 

The need for more bricklayers meant that wages had to be increased from 5 shillings (25 pence) per day to 6 shillings (30 pence) or more. It consumed nearly a million cubic yards of concrete. A special mill was built at Crossness to produce this, together with a railway to distribute it

The project made pioneering use of Portland cement, which was water resistant, rather than conventional lime mortar. Because its manufacturing process was so new, Bazalgette insisted on a draconian regime of quality control, with every batch being tested before it was used.

The southern drainage scheme was completed in 1865 and the northern one in 1868. Most of the pumping stations were opened by Royalty, and some of the enormous sewage pumps were even named after members of the royal family.

Joseph Bazalgette was knighted for his considerable services to London in 1874 and retired in 1889, dying in Wimbledon two years later.

But you’re still dumping all the sewage in the Thames!

Matt Brown from London, England, Creative Commons Attribution 2.0

Bazalgette’s scheme moved London’s sewage ‘out of sight’ (and smelling distance) of Parliament but it still dumped it into the Thames. A steady tide of complaints now came from those downstream. 

One particularly nasty incident in 1878 focused attention on the state of the river. The pleasure steamer Princess Alice collided with a freighter and sank near the outfalls, with the loss of 600 lives. There were suggestions that many of the dead had been poisoned by the river water rather than simply drowning.

Pressure from MPs in the 1880s forced the first ‘treatment’ of the sewage. The solid waste was settled out at Beckton and Crossness and only the liquid waste was discharged into the Thames. There were attempts to sell the solid sludge as fertiliser but there was little demand. So in 1887, a fleet of six sludge vessels were commissioned. These sailed down the Thames and dumped it out at sea. Even this is now regarded as unacceptable and was prohibited by an EU Directive in 1998. 

The proper recycling of sewage as a potential fertilizer remains as interesting a challenge today as it was in the 1850s.

A photo taken from the Thames in London, looking towards The Shard and surrounding glass-fronted buildings

Unfreezing Urban Infrastructure

Late feminist scholar, Susan Leigh Star, wrote that to fully appreciate the critical role ‘boring things’ like infrastructures play in how we live, it is necessary to ‘unfreeze’ them. So let's do it.

What she meant is that - especially in the Global North - it can be easy for networks of transportation, communication, supply, and sanitation to remain taken for granted as a sort of static background of roads, cables, lines, and pipes to our everyday activity, giving us no reason ever to explore their full complexity and contribution.

A long boat sits shoreside on the River Thames. A yellow and red crane extends upwards from it.

Copyright: © Alan Gardiner | 

To bring such unexciting infrastructures to life, Star used what she called certain ‘tricks of the trade’. One was to pay attention to the typically ignored, behind the scenes maintenance work that all infrastructures require to keep them going, while another was to take any opportunity possible to follow infrastructure ‘in the making’. In The Five Billion Pound Super Sewer series we witness the sanitation infrastructure of London through both of these lenses, and as a consequence get an unusual and privileged insight into a key way in which the city is made and kept habitable. On the one hand, we get to follow the ‘flushers’ who continually work to clear the existing Victorian sewer system of some of the detritus of twenty-first-century urban life like wet wipes. And on the other, we are offered remarkable access to the construction of various aspects of the new ‘Super Sewer’ itself as it emerges in and is gradually stitched together between various sites in and around London.

Encountered in this somewhat different light, it can perhaps make a bit more sense why infrastructures have become a topic of renewed interest for geographers and other urban scholars over the last couple of decades. Through this work - often inspired by Star and her colleagues - engaging with urban infrastructures has come to be considered as absolutely key to understanding the past, present, and future of cities and the ways of life that happen there.

Infrastructures are often 'taken for granted'

Infrastructures have become understood as the very conditions of possibility for urban life. Cities depend on circulations – of people, materials, goods, waste, energy, and information – it is urban infrastructures that make those circulations possible. Without them, the practical issues posed by large numbers of people living together would not be solvable. Consider, for example, how the introduction of Bazalgette’s underground sewage system during the nineteenth century helped transform the habitability of London for people of all sorts of backgrounds.

City infrastructures do not always serve equally

Urban infrastructure is continually making a difference in the city; its availability or scarcity makes certain parts more habitable than others and some activities more or less possible

Infrastructures have become understood as patterning as well as producing the habitability of cities. In other words, if infrastructures pervade cities and make urban ways of living possible, that does not mean that they are everywhere the same or make everywhere equally habitable. By their very nature, infrastructures tend to take the form of networks, and networks – whether of sanitation or roads or data - connect some places rather than others. Urban infrastructure is continually making a difference in the city; its availability or scarcity makes certain parts more habitable than others and some activities more or less possible. Differential access to working infrastructure is an issue in all cities but is felt most acutely in urban developments in the Global South.

In other cases, the patterning of cities by infrastructure is less about what is absent from a certain area and more about what is present. There is a long history of particularly undesirable aspects of urban infrastructure such as sewage treatment plants, rubbish dumps, and polluting factories, located in areas populated by less affluent citizens, and generating evident inequalities. We should always ask, therefore, who benefits from the particular ways in which urban infrastructures make the city?

Urban infrastructures must continually be maintained and often improvised

If infrastructures have become understood as keeping cities operating, moving, liveable and social, they have, in turn, become recognised as never just working but instead as being always in the making.

Not just in the sense that new infrastructures are continually built somewhere or another, but more pointedly regarding the fact that existing urban infrastructures whether new or old require - as noted earlier by Star - constant repair or renewal. Like the infrastructure itself (when it is functioning correctly) this work goes mostly unrecognised and undoubtedly uncelebrated. However, when one considers the sheer range of activities involved, and the sheer size and extent of modern cities, it soon becomes clear that this work could not be more crucial. As the ongoing lead-poisoning water crisis in the city of Flint in the United States demonstrates only too well, whose infrastructure gets maintained, when, where, and at whose expense is a critical question for urban living everywhere.

Adam Cohn under Creative Commons BY-NC-ND 4.0 license

If the notion of maintenance can offer a sense of return to normality or a stable situation, another notable kind of infrastructure work can be considered more creative in character in the mind that it involves improving the liveability of parts of cities, where there is not even a great deal of existing conventional infrastructure to repair or renew. Such ‘improvisation’ of infrastructure, as it has been called, shapes many kinds of urban infrastructure from housing to mobile phone use - particular in cities of the Global South - but always involves a learning about and tinkering with urban space and its materials to making a marginal situation work better for its inhabitants.

To take but one example related - like the Super Sewer series - to the topic of sanitation, in their research in the informal settlements of the Rafinagar district of Mumbai, India, geographers Colin McFarlane, Renu Desai, and Stephen Graham (2014) report on how - faced with wholly dysfunctional sanitation provision - residents have built makeshift shared toilets made from cloth, timber, jute and iron sheets. Developed in part because climatic changes have made existing shared sanitation facilities increasingly inaccessible or prone to flooding. The construction of shared toilets relies on residents contributing their labour, skills, or money. Over time, and with experience, some of those improvised toilets have become an established part of everyday life in the settlement, while nevertheless continually facing the threat of unannounced demolition.

According to the urban scholars, AbdouMaliq Simone and Edgar Pieterse, it is such small, incremental acts of improvisation, more than mega-projects like the Thames Tideway Tunnel, that offer the best model for how different kinds of infrastructures might be woven together to build cities that take seriously the environmental challenges as the drivers and significant victims of accelerated climate change. For Simone and Pieterse, if it is correct to say that urban infrastructures play a central role in making cities habitable and should also be considered as key sites at which we should experiment with finding ways of keeping cities - and the planet - habitable in the so-called Anthropocene era. They propose the model of an ‘adaptive city’ (2017) in which low-cost, labour-intensive approaches to urban infrastructure that are typical of improvised infrastructure are connected with broader city-wide, regional and national systems to generate water, energy, and transport infrastructures that both serve the majority of city dwellers and are more sustainable than those offered by current models of provision.

Building urban infrastructures for an adaptive city

What would this look like in London? Many people in the city regret that more distributed, localised and integrated ways of managing the issues of water infrastructure that London faces - collectively known as Sustainable Urban Drainage Systems (or SUDS) - were not given greater consideration during the early review period. Whether Simone and Pieterse are correct in suggesting that it is only by weaning ourselves off a certain engineering-dominated approach to urban infrastructure that we will find more sustainable infrastructure systems better suited to our changing planet, only time will tell.

Meet the academics

Dr Bob EverettLecturer in Renewable Tech, Faculty of Science, Technology, Engineering and Mathematics VIEW FULL PROFILE
Dr Bob EverettLecturer in Renewable Tech, Faculty of Science, Technology, Engineering and Mathematics

I am a lecturer in Renewable Technology at The Open University and have contributed to many Energy and the Environment OU courses, and to multiple books on Renewable and Sustainable Energy. I have been fascinated by London's infrastructure since childhood and love visiting the parts of the capital that most tourists never see.

My research has been on low energy housing and I have been working on assorted renewable energy projects and those involving energy in buildings since 1979. These have included hospital design and energy assessment.

In January 2014 I appeared in a BBC East programme about low energy housing in Milton Keynes (the topic of my PhD). I have also advised (through the Newcomen Society) on a 2015 BBC Four programme on the history of Diesel engines.

Dr Nick Bingham, Senior Lecturer in Geography
Dr Nick BinghamSenior Lecturer in Geography - School of Social Sciences & Global Studies GeographyVIEW FULL PROFILE
Dr Nick Bingham, Senior Lecturer in Geography
Dr Nick BinghamSenior Lecturer in Geography - School of Social Sciences & Global Studies Geography

Nick's interest in taking seriously the role that non-human entitles (whether they are insects and microbes or technologies and data) play in social life has involved him researching topics as diverse as food safety, the bee crisis and smart cities.

Professor George Revill - Professor of Cultural Historical Geography
Professor George RevillProfessor of Cultural Historical Geography - School of Social Sciences & Global Studies GeographyVIEW FULL PROFILE
Professor George Revill - Professor of Cultural Historical Geography
Professor George RevillProfessor of Cultural Historical Geography - School of Social Sciences & Global Studies Geography

George has worked on a number of OU environmental and social science modules. Current research brings issues of sound, mobility, communication and landscape together in terms of acoustic geographies of space, place, landscape and environment. 

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