History makers: Joseph Bazalgette

This week, we celebrate a civil engineer whose unglamorous project transformed the lives of people around the world.

Despite coming to prominence in the age of great engineers, Joseph Bazalgette stood out. No other engineer in the Victorian period, not even Brunel, undertook a project quite as ambitious or transformative as Bazalgette did, when he led the project to build London’s municipal sewer system. The system, and the similar sewer systems it inspired around the world, may constitute the single greatest leap forward in public health and sanitation in history. His legacy continues to save countless lives to this day.

In the mid-nineteenth century, London was the centre of the world’s greatest empire, yet it remained a terrible place to live for the bulk of its inhabitants. Most of the city’s population lived in appalling poverty, and with that came disease. Outbreaks of disease were rampant and up to half of children did not survive infancy. A cholera epidemic between 1848 and 1849 killed over 14,000 Londoners; another outbreak in 1853 claimed a further 10,000 lives.

Joseph Bazalgette

For centuries, it had been thought that cholera was spread by miasmas or foul air. This was because outbreaks of diseases like cholera tended to strike in places where the stench of sewage was strongest. Although the pioneering work of Dr John Snow had already shown that it was sewage contaminating the water supply, not air pollution, that was causing cholera outbreaks, his theories were yet to be widely recognised. At the time, open shores still carried the city’s effluent into the Thames, turning the river itself an enormous open sewer.

As the city expanded, there was some clamour to improve how London dealt with its sewage. But it was not until the Great Stink of 1858 that parliament, located on the banks of the stinking river, finally decided to act.

A network of enclosed sewers was to be built to enclose the smell, and with it what they believed was the cause of disease. Bazalgette had recently been appointed chief engineer of London’s new Board of Metropolitan Works, and found himself responsible for the project. Bazalgette’s tendency to think big was what made him remarkable. He was to elevate what could have been a simple infrastructural improvement into one of the greatest engineering feats in history.

The scale of the project he planned was immense. Almost 160 km of intercepting sewers would be fed by 720 km of main sewers, which in turn were fed by 21,000 km of tributary sewers serving every street in London. Far from being seen as unglamorous, the project was rightly celebrated as one of the wonders of the age. Due to the limitations of the time, the raw sewage would ultimately still enter the Thames untreated, but he ensured that it entered the river downstream on the Thames estuary, away from the major population centre. The pumping stations, charged with the unsavoury task of shifting millions of litres of effluent away from the city, were symbolic of the grandeur afforded this project. Pumping stations today are often built to blend in and go unnoticed; Bazalgette’s stations made a statement. They were large sturdy structures, with interiors adorned with elaborate and brightly coloured iron work; they were ostentatious and proud monuments to progress.

His status as a visionary is well deserved. Bazalgette’s drive to see his project completed to the highest standards meant that he never rested. He spent his days dashing about London to inspect personally every intersection of the web of sewers as they branched across the city, taking meticulous notes as he went.

Bazalgette wanted his sewer system to last for centuries, but was well aware that London, already the largest city on earth, would continue to grow exponentially. He calculated the absolute maximum amount of effluent a single human could produce, multiplied it by what was then the population of London, and then designed his sewers to cope with four times that volume. This made sure his system would be able to cope as the city expanded over the coming generations. As a result of his planning, the system was even able to cope with the explosion in population density that came with the postwar construction of high-rise blocks. Bazalgette famously responded to criticism of the mounting costs of the project, and accusations that he was over thinking what was meant to be a simple infrastructure project, by saying ‘Well, we’re only going to do this once and there’s always the unforeseen’.

Today, big infrastructure is frowned upon; we are encouraged to think small. In parts of the world that still don’t enjoy the kinds of sanitation that Londoners have had for over 150 years, people are told to use compost toilets. Here in the West, we, too, are often told that new infrastructure projects are unfeasible or too costly. Whether it’s high-speed railways, power stations, new airports or reservoirs, we are often instructed to make do with what we have. We would all benefit from a return to the vision and extraordinary boldness of Joseph Bazalgette.



comments powered by Disqus