In November 2021, FLUSH's Founder was working in London (UK) and had the chance to visit the Crossness Pumping Station for a tour. The Crossness Engine Trusts team gave a fascinating tour and shared surprising details on London's sanitation story. This blog will get into the Crossness Pumping Station. But, first, we need to talk more about London's sewer history and its significance.
Before London's Victoria Sewers
London has been no stranger to sewers; the Roman Empire was famous for implementing underground sewers, including across cities on the British Isles. However, sewers weren't always used exclusively for transporting human waste between the Roman Empire and Victorian England. Instead, sewers back in the day focused on managing the run-off from the streets and making sure land drained rain somewhat. Henry VIII passed the Statute of Sewers in 1531 to regulate land drainage and prevent flooding.
If sewers were for just rainwater, then what about human waste – where did all of the poo go? Unfortunately, after the Roman Empire fell, underground sewers that included human waste often fell into disrepair, and people threw chamber pot waste onto the streets. Without safe sanitation systems like sanitary sewers, poo will always end up in a waterway. In London, that was the Thames River, which is a tidal river that ebbs and flows into the sea. As London grew over the centuries, the pouring of waste into the river that got stuck in the river's tides meant that the Thames was becoming overwhelmed with sludge.
By the 19th century, London had 200,000 cesspits that night soil men would empty and sell the waste to farmers at nearby farms for fertilizer. The rest of London's waste was ending up in the Thames (not just human waste, but industrial and animal waste too). The Thames was dying from pollution, but this didn't stop people from relying on the river for drinking water. In 1856, there were 9 water companies in London, and 5 of them sourced water they sold to households from the Thames. Essentially, people were poisoning themselves with water contaminated from their own waste. Diseases were rampant, and from the 1830's cholera outbreaks were common.
In 1858, the Thames was dead and stinking. In the summer, London's smell became terrible, called The Great Stink. Parliament was sure the smell was going to kill them, as miasma remained a popular theory. Because of this, they and mobilized political action to get the Metropolitan Board of Works £3 million to create new underground sewer systems - closer to £200 million today. As Chief Engineer of the Metropolitan Board of Works, Joseph Bazalgette, was tasked with designing and constructing London's first integrated sewer system.
Bazalgette's Engineering Feat
Bazalgette started his engineering work developing Britain's railways, which allowed him to understand land use and drainage. While responsible for a lot of London's construction at the time – over £1 billion in today's terms – he is probably better known for the Thames Embankments in London. However, perhaps the crown jewel of his work was the construction of London's sewer system, which forms the system's backbone still in use today.
London wasn't the first place in the UK to develop an integrated sewer system; a decade earlier, James Newlands developed Liverpool's sewer system. His work was able to reduce waterborne diseases to the point that Liverpool's life expectancy doubled.
However, by the mid-19th century, due to its rapid increase in population, London was the largest city in the world. In 1859, Bazalgette began work on the largest civil engineering project ever undertaken at the time.
Bazalgette planned to construct a drainage system right across London and its environs to enable the sewage and surface water to flow safely underground, via gravity, and be carried eastwards to be discharged into the Thames well away from the heavily populated Victorian city of London.
1,100 miles of street sewers and 82 miles of intercepting sewers were constructed running from the west of London to the east. On the north side of the Thames the sewage flowed to Abbey Mills Pumping Station - the Northern outfall – and on the south side, to Crossness Pumping Station on the Erith Marshes, the Southern Outfall - 12 miles downstream from the city.
At Crossness four mighty steam-powered beam engines – the largest in the world - lifted the waste from the sewage wells deep underground and pumped it into a 6.5 acre covered reservoir with a holding capacity of 25 million gallons. Twice a day at high tide, the Crossness station released sewage from the reservoir into the Thames to be carried downstream on the ebbing tide and out to sea.
About Crossness Pumping Station
Images of Crossness Pumping Station (left to right): The Metropolitan Board of Words initials in the ironwork; the lovely outside area; the entrance to the steam pump room; the steam pumps. (Credit: FLUSH/Kimberly Worsham)
Remarkably, only six years after construction had begun, Crossness was officially opened by the Prince of Wales, Albert Edward, on April 4th, 1865. Three years later, Abbey Mills and the northern system were also operational. Bazalgette's new drainage system for London eradicated cholera from the city and greatly improved the health and quality of life for Londoners.
The pumping station had a beautiful side to it that went beyond practical needs, as well. Because of the miasma theory, Bazalgette put the reservoir underground and covered it with a big green space with houses for the workers to live on with their families since work at the station was 24/7. Also, the building was a beautiful Gothic design and handsomely painted for the upper-class to ogle and appreciate the amazing civil engineering feats of the empire. The designs in the engine rooms were elaborate reds and greens, with the Metropolitan Board of Works initials molded in iron decorations everywhere. The place is beautiful, and Victorians loved looking at it when it opened – on opening day on April 4th, Prince Edward was there turning on the engines in a big party.
The Accident that Changed Crossness
Not long after Crossness was online, people started wondering if the Thames' sewage problem was simply moving downstream and creating problems elsewhere. By 1878, those concerns changed Crossness's future when tragedy struck.
On September 3rd, a paddle steamer called the SS Princess Alice took hundreds of people on a day trip out of London. The boat went eastward and up the coast (we don't know how many people, but it was a lot). Unfortunately, by the time it got to the inlet of the Thames, a much larger vessel, the Bywell Castle, started approaching it a bit too quickly. After poor maneuvers from both boats, the vessel collided with Princess Alice, chopping it in half. As the boat sank, people sank with it – in the boat and out. The Bywell Castle saved some people, but an estimated 650 people died in that accident.
How did they die? The investigation after the accident concluded that some died by drowning, others by ingesting sewage.
The accident had happened close to the Northern Outfall while millions of gallons of raw sewage from Abbey Mills was released into the Thames.
Remember – Bazalgette, the creator of the Crossness Pumping Station – was a miasma guy. He wasn't thinking about waterborne diseases when he created London's sewers – he just wanted to move the stink somewhere else. Germ theory came afterward, and only after the sewers were completed did people start understanding that contaminated water was the key disease vector.
This tragedy encouraged authorities to start reconsidering how it discharged waste out of the city. By the 1880's sedimentation tanks were constructed at Crossness to separate the solid waste, called sludge, from the liquid waste. Although the liquid waste continued to be released into the river, the sludge from sewers was now loaded into barges and transported daily along the Thames where it was dumped out at sea. This was a practice that continued until 1998 with the enforcement of new EU regulations.
It was a remarkable history lesson for us at Crossness, and it was a great reminder that a lot of the incredible sanitation systems we have today happened in response to tragedies – whether they be outbreaks or boating accidents. It is easy to forget that the construction of our original modern sewers often came out of urgent necessity in response to terrible events. Also, it was fascinating to learn that our sewers work brilliantly, but not for the reason that Bazalgette had originally anticipated – the dirty water was the issue with our sewage that needed managing, not dangerous air.
Images (left to right): The non-restored area of the steam pump room; A column with Bazalgette's head in relief (Credit: FLUSH/Kimberly Worsham)
Because of changing disposal methods, rapid population growth, and new technologies, the Crossness Pumping station eventually closed in the 1950s when the city built a waste treatment nearby. The underground areas of the pumps were filled with sand to make sure the leftover sewage didn't release toxic gasses while it stayed unused. It stayed dormant until the 1980s when a preservation group of volunteers called the Crossness Engines Trust began restoring and conserving the station, even bringing one of the mighty beam engines back into steam!
The Trust's restoration work continues, and Crossness is now open to the public on Open Days for guided tours and to take part in its learning and outreach program for schools, universities, and the local community.
A big thank you to the Crossness Engines Trust team - particularly Petra Cox -for giving us a fantastic tour and fact-checking this blog post for us!