200 years ago it wasn't just the River Fleet that stank, it was the whole city. One million Londoners produced a heck of a lot of sewage, most of which ended up in the capital's two hundred thousand cesspits, or in the street, or floating down towards the Thames. Conditions were at their worst close to rivers, such as the Fleet, where domestic water-closets often discharged directly into the stream. As the 19th century progressed outbreaks of cholera became more common, sometimes killing thousands of people, and the smell of the city on a hot day became intolerable. The situation came to a head during the 'GreatStink' of 1858 when the Thames became heavily polluted during a particularly hot summer. Lime-soaked curtains were hung from the windows of the House of Commons in a vain attempt to keep out the stench. Thankfully a solution was at hand.
Enter JosephBazalgette - an engineer with a vision. He believed (rightly, as it turned out) that London's stinky problems could be solved by a series of giant intercepting sewers which would divert brown waste safely away from the rivers in the centre of town. These sewers used gravity (and 318 million bricks) to deliver their cargo to two pumping stations at Crossness and AbbeyMills, both suitably downstream of the capital, where sewage was stored in reservoirs until the ebb tide and then released into the Thames. Three east-west sewers converged at Abbey Mills (just down the road from my house, so I've written about it before). The northernmost sewer fed down from Kentish Town and Hampstead, intercepting the waters of the upper Fleet along the way, while the middle sewer passed from Notting Hill through Clerkenwell. But when it came to constructing the Northern Low Level sewer, there was nowhere else for it to go except along the banks of the river Thames itself.
The VictoriaEmbankment, constructed by Bazalgette between 1864 and 1870, provided a new waterfront for central London and solved four important problems. Firstly it hid a giant sewer pipe, safely transporting the effluent of west London towards less affluent east London. Secondly it provided the perfect location for the construction of a new underground railway - today the District Line between Westminster and Blackfriars. Thirdly by reclaiming land from the Thames it narrowed the river and produced stronger defences against potential flooding. And fourthly a new four-lane road built on top of the Embankment relieved growing traffic congestion along Fleet Street and the Strand. Drivers whizzing along the current riverside dual carriageway probably don't realise that all of Chelsea's excrement still flows along beneath them.
Bazalgette's sewer system also finally demoted the Fleet from a buried river to an underground storm relief drain. Where once a babbling brook flowed into a navigable inlet, now sludgy brown liquid flows through a network of subterranean brick tunnels. Several connecting branch sewers converge on this dank Stygian puddleway, and one of the chambers lower down is as big as a cathedral with great vaulted ceilings. This is not somewhere that most people would choose to visit, but JD and Stoop specialise in underground drain exploration and they've made two journeys down the Fleet sewer during the last year. Their last, and most dangerous, expedition was back in June when they (and a daring Time Out journalist) made it nearly all the way down from St Pancras to the Thames.
Down in the sewers you're always at the mercy of the weather, or some waterworks operative diverting the flow from a channel above, so the trio's journey back up the sewer was rather more treacherous as the water level increased.
Read more here (or in last week's edition of Time Out). Oh, and they don't recommend you try following in their footsteps, just enjoy their photographs of the Fleet sewer instead. [More (slightly illegal) Urban Exploration links here]