London Super Sewer
London is a notoriously expensive city, but even so, a price of £1 million for a one-metre trip is pretty steep.
In this case, however, the price reflects the many challenges involved in moving all 556 tonnes of the PS Tattershall Castle, 100 metres to the west of its former mooring location on the Westminster bank of the Thames, in order to make way for the forthcoming “super sewer”. If that sounds expensive, it’s, if you’ll pardon the expression, just a drop in the ocean compared to the overall projected costs of £5 billion for this ambitious engineering project.
The history of London’s sewers
London’s main sewer was once the river Thames itself, with other local sources of water also serving as auxiliary sewers. This wasn’t a great system even in the earliest days of the city and by the mid-19th century, it had become a lethal one. Initially the dangers of the Thames were largely overlooked. It would be harsh to say ignored since science was less advanced and the dangers of waterborne disease were much less understood. It was more commonly believed that illnesses were transported by air which is why the Great Stink of 1858 caused such a panic. This odiferous event brought the problem to Parliament’s doors (literally, Parliament was in session that summer) and MPs rapidly came to the conclusion that urgent action needed to be taken. Enter Joseph Bazalgette and one of the most spectacular engineering projects the world had ever seen (in fact even by today’s standards, it is still very impressive).
From the 19th century to the 21st century
When Bazalgette designed his network (some might say labyrinth) of tunnels, the population of London was around 2 million and environmental standards were somewhat lower. Specifically, it was considered quite acceptable to continue to pump sewage directly into the Thames without any form of treatment, just as long as it was kept well clear of the main residential and commercial areas (including, of course, Westminster). Now the population of London is about 9 million and on an almost continuous growth path to the tune of about 100,000 people per year. While the city as a whole is often very keen on preserving its history and traditions, one tradition it does not want to see back is that of raw sewage being pumped straight into the Thames, which is exactly what’s happening at the moment, albeit only when there is heavy rainfall, which raises the water level.
Project super sewer
In some ways, the new super sewer project is somewhat reminiscent of Bazalgette’s original project. It is massively ambitious, massively expensive and, generally, just massive. It is also, fundamentally, intended to deal with the problem of raw sewage in the Thames by diverting it to the outskirts of London. The big difference this time is that it will be processed in a modern sewage plant before pumped into the river. As is often the case with major engineering projects, the super sewer project requires a certain degree of short-term pain for long term gain. In practical terms, this means the requirement to accommodate the necessary building works, hence the need to move the PS Tattershall Castle. The finance for the project is mostly being provided by the private sector, however, the cost will ultimately be passed on to Thames Water customers through an increase in water charges. Londoners may not be thrilled by this news but they will probably find it easier to swallow than a sewage-filled Thames, particularly given that London’s economy has an extensive tourist sector and tourists are unlikely to want to see the contents of people’s toilets.
