Have you ever wondered what happens when you press the ‘Flush’ button on your toilet and wondered where all the contents of your toilet-bowl vanish off to? Everyone’s wondered that at one point or another in their lives. Have you ever pondered what happened to mum’s wedding-ring after it got washed down the sink and didn’t show up in the U-bend at the bottom of the pipe? Back in Victorian London, people didn’t have to wonder about things like this. They knew where their sewerage went…and that’s exactly what this article is about.

Admittedly, writing an article about a 160-year-old sewer-system is not the biggest thing on the list of subjects to write about for any writer, but the story London’s Victorian sewer-system is about a lot more than huge pipes in the ground that haul away rainwater, bodily waste and general sewerage…It’s about an ambitious and dangerous civil engineering project, it’s about the vastly changing opinions on the causes of disease, it’s about ambition and determination and, as is more often the case than is not, it’s about how the hands of the mighty are only swayed by mighty events. This is the story of Sir Joseph Bazalgette and the sewers of London.

London, 1850

The Industrial Revolution was not called such for no reason at all. It revolutionised alright. It revolutionised bigtime. It revolutionised everything in the world. And unfortunately, it also revolutionised London. The city’s population skyrocketed during the Victorian era, with more and more people surging into the British capital looking for money, work and a better livelihood for themselves and their families. Slums sprang up, houses were built, new businesses were opened and all over town, people were settling into their new lives.

But as the city of London grew above ground, below the streets and buildings of the great metropolis, there was a horrible, unimaginable and unseen disaster waiting to explode.

For centuries, London had existed without sewers. What few public sewers and drains that there were existed as old trenches or tunnels which were covered over as the city grew, or were pipes, channels or streams that ejected their contents directly into the River Thames. The majority of households still relied on daily visits by the nightsoil-carrier or gong-scourer, who would come by each evening to empty their chamberpots and cesspits. What drains that did exist were by the 1850s, centuries old. They were frequently blocked by sewerage or overwhelmed by the frequent heavy rainfalls for which London is globally famous. Streets flooded, sewers backed up and overflowed and disease and stench were rife throughout London. By 1850, there had already been one outbreak of cholera in which over 14,000 Londoners died from drinking the incredibly contaminated water, which had been polluted by the overflow of sewerage within the confines of London. A solution to this increasingly unavoidable problem was needed…and it was needed yesterday!

In charge of the sanitation of London was a body of men called the Metropolitan Commission of Sewers based in Soho Square. Try as they might, they were unable to find a single reasonable method of removing sewerage from London. This all changed in 1849. In August of that year, a new assistant engineer was appointed to the Commission, a thirty-year-old engineer named Joseph Bazalgette.

Bazalgette didn’t have any idea of how to combat the growing problem of London’s sewerage either, but when he saw the products of those people who thought they did, he began to realise that something serious had to be done. Unable to find a way to remove sewerage from London, the Commission printed a letter in the Times newspaper, asking its readers to post suggestions to them on how to clean up London. It was up to young Bazalgette to sift through every single one of the 137 replies…none of which he deemed suitable for replacing the narrow, clogged and overflowing channels that served as ‘sewers’ up to that point in London’s history.

In 1855, the Commission of Sewers was replaced by a new body, the Metropolitan Board of Works. Another cholera epidemic (in 1853) had proved how ineffectual the Commission had been in finding a solution. The MBW as it was sometimes called, apart from being a new organisation, also had a new leader: Joseph Bazalgette.

Planning the Sewers

Now that he was in charge of his own organisation, Bazalgette set to work. He carried out surveys and measurements, he examined the tidal flow of the River Thames, he carried out explorations of the old sewers and checked their general condition and he drew up bold plans for a vast network of tunnels underneath London which would draw the sewerage away from the capital to pumping-stations where it could be pumped out into the Thames each day at the changing of the tides. The poweful river-currents would drag the sewerage right out to sea and London and the River would be clean and healthy forevermore.

Or at least, that was the plan. The reality was very different.

The government was not pleased. They complained endlessly that Bazalgette’s plans were…too dangerous…too big…would take too long to build…were far too expensive…involved tunnels that were not long enough as to draw the sewerage a satisfactory distance from London…and which the government, as a result, would not give him permission to build. The Metropolitan Board of Works…ground to a halt. For three years, all that Bazalgette could do was redraw his plans…over…and over…and over…and over…and over again. And every single time, the government said ‘No’. All the while, the threat of another catastrophic cholera outbreak was lingering just below the surface.

Cholera and Snow

While Bazalgette struggled with the government and its refusal of his bold new plans for London’s sanitation, nearby, physician Dr. John Snow was battling with the London medical establishment, a battle he would eventually win…posthumously.

Dr. Snow was a researcher and a theorist. As a physician, he was fascinated by the spread of disease and in the 1850s, the disease to study was cholera. Leading medical minds of the time were convinced that cholera was spread via “Miasma” (‘My-as-ma’), a term that literally means ‘Bad Air’. The Miasma theory came up in the early Georgian period to replace the previously widely-held theory of the Four Humours, a medical theory that dated back thousands of years to the ancient Greeks…and which had absolutely no scientific basis at all. The Miasma Theory purported that strong stenches, odours and smells spread disease through the air and that such foul contaminants came from places such as graveyards, rubbish-tips, chimneys, polluted waterways and the bad breath of ordinary people. It was the first, semi-scientific link between the containment of disease and the vital necessity for cleanliness. However, in mid-Victorian times, in an age where the Germ Theory that we know today, would not arrive for several more decades, everyone believed that all diseases were airborne miasmas and that the best way to handle such miasmas was to keep things clean and the air fresh.

This did not, unfortunately, extend to the vital necessity of keeping waterways clean. The idea that disease could be waterborne as well as airborne, simply hadn’t entered the minds of the medical community. But it had entered the mind of Dr. Snow. Through careful plotting, study, observation and record-keeping, he determined that water consumed from a particular pump in Broad Street, East London, caused an unnaturally high rate of cholera cases. By studying which people on Broad Street drank what, when and where, he was able to trace their illnesses back to contaminated water and therefore prove that cholera was a waterborne disease…something that many other medical minds of the day, cast off as ludicrous.

Building the Sewers

Ever since the late 1840s, London had been struggling with the monumental task of trying to find a way to remove vast amounts of sewerage from its streets and arterial river, the Thames. Theories, proposals, ideas and even plans had been put forward as possible solutions, but none of them were even so much as entertained by the government, all cast off as being…too expensive…too dangerous…too impossible…too outrageous. And so for ten years, nothing was done.

That all changed in 1858. By this time, London had become so incredibly polluted that the air had become almost unbreathable. In the summer of that year came the famous ‘Great Stink’. Extreme summer temperatures caused the water in the River Thames to heat up by several degrees and this caused the sewerage contained within it, to give off powerful odours and smells, which wafted all over London. So bad was the smell that Parliament had to relocate outside of London to get away from the unimaginable, nose-wrinkling, eye-watering stench! How could such a great, powerful, technologically advanced city at the heart of a great empire smell like something that had crawled under a bed and died? Finally forced to face the inconvenient truth that London required a serious and long-term solution to its sanitation problems, the government contacted Joseph Bazalgette, the head engineer of the Metropolitan Board of Works and asked him how quickly he could start digging.

This cartoon from 1858 shows Father Thames (right) introducing his children (Diptheria, Scrofula and Cholera) to the fair city of London (left). This shows just how bad the pollution of the Thames had become by the time of the Great Stink

The project was never going to be easy. And it was never going to be cheap. London had existed for centuries and had grown for centuries, without any modern sewerage system of any kind at all…and now in a matter of years, they were going to try and undo the lack of foresight that had lasted ever since London had been established back in Roman times! Bazalgette was given three million pounds sterling (unadjusted for inflation) and told to start at once.

Finally given the green light, Bazalgette immediately began surveying the land, measuring distances and determining exactly where each and every tunnel, channel and watercourse would go. How big it would have to be, how high, how long and most importantly…what angle of gradient the tunnels would need to have. There was no space for large, steam-powered pumping-appratus in the middle of London, so every last cubic inch of the sewers had to be angled downwards, towards the East, where the force of gravity would draw the sewerage out of London and down the Thames Valley.

Where possible, the sewers were constructed just a few feet below street-level using the ‘Cut-and-Cover’ method which was also being used for some of London’s Underground subway-tunnels. It was simple…Dig a trench, build the tunnel and then put the earth back on top. In total, there were to be five huge main tunnels, three going underneath London north of the Thames and two going under the areas of London south of the Thames. These great sewers were to intercept smaller sewers that ran north-south (towards the river’s edge) and then take the sewerage far out of London to enormous holding-tanks. Here, vast, steam-powered pumps would pump the sewerage into the river each day at the changing of the tides. As the Thames is a tidal river, all that the people at the pumping-stations had to do was to wait for the tide was at its highest and then, when it began to change, discharge the sewerage. The strong currents would pull it right out to sea.

Although Bazalgette was as careful as possible with his tunnel-construction, insisting on all safety precautions, quality-control checks on the cement and the millions of bricks that would be used to construct the tunnels, a few men did die in their construction; mostly from cave-ins or other work-accidents.

Completing the Sewers

The main components of the sewers were completed in 1865. On the 4th of April, the Prince of Wales (the future King Edward VII) turned on the pumps at the Crossness pumping-station outside of London and for the first time in centuries, London’s water supply began to clean up its act. Cholera disappeared from London as pollution of London’s water-supply began to disappear. It was for this action of constructing London’s sewers, and of many other engineering successes of his throughout London, that in 1875, Joseph Bazalgette was knighted by Queen Victoria and became Sir Joseph Bazalgette.

The Sewers Today

London has grown enormously since Bazalgette’s time. Today, his original, Victorian-era sewer-system makes up only a small portion of the additions that have been made in the over 100 years since he died in 1891. But even without modern additions, Bazalgette was a man of foresight. He had made the sewerage-tunnels as big as possible so that they were able to take twice the amount of even the highest level of rainfall and sewerage that London could produce at the time, meaning that it wouldn’t be necessary for decades to expand and improve his original system until well into the 20th century.