The London sewerage system is part of the water infrastructure serving London,
England. The modern system was developed during the late 19th century, and as
London has grown the system has been expanded. It is currently owned and
operated by Thames Water and serves almost all of Greater London.
History During the early 19th century the River
Thames was an open sewer, with disastrous consequences for public
health in London, including cholera epidemics. These were caused by
enterotoxin-producing strains of the bacterium Vibrio cholerae. Although the
contamination of the water supply was correctly diagnosed by Dr John Snow in
1849 as the method of communication, it was believed that miasma, or smell, was
responsible right up to the outbreak of 1866. Proposals to modernise the
sewerage system had been made during 1856, but were neglected due to lack of
funds. However, after the Great Stink of 1858, Parliament realised the urgency of
the problem and resolved to create a modern sewerage system.
Joseph Bazalgette, a civil engineer and Chief Engineer of the Metropolitan Board
of Works, was given responsibility for the work. He designed an extensive
underground sewerage system that diverted waste to the Thames Estuary,
downstream of the main centre of population. Six main interceptor sewers,
totalling almost 100 miles in length, were constructed, some incorporating
stretches of London's 'lost' rivers. Three of these sewers were north of the
river, the southernmost, low-level one being incorporated in the Thames
Embankment. The Embankment also allowed new roads, new public gardens, and the
Circle line of the London Underground. Victoria Embankment was finally
officially opened on 13 July 1870. The intercepting sewers, constructed
between 1859 and 1865, were fed by 450 miles of main sewers that, in turn,
conveyed the contents of some 13,000 miles of smaller local sewers.
Construction of the interceptor system required 318 million bricks, 2.7 million
cubic metres of excavated earth and 670,000 cubic metres of concrete. The
innovative use of Portland cement strengthened the tunnels, which were in
good order 150 years later. Gravity allows the sewage to flow
eastwards, but in places such as Chelsea, Deptford and Abbey Mills,
pumping stations were built to raise the water and provide sufficient flow.
Sewers north of the Thames feed into the Northern Outfall Sewer, which feeds into
a major treatment works at Beckton. South of the river, the Southern Outfall
Sewer extends to a similar facility at Crossness.
During the 20th century, major improvements were made to the sewerage
system and to the sewage treatment provision to substantially reduce
pollution of the Thames Estuary and the North Sea.
Modern development needs The original system was designed to cope
with 6.5 mm per hour of rainfall within the catchment area, and supported a
smaller population than today’s. London's growth has put pressure on the
capacity of the sewerage system. During storms, for example, high levels of
rainfall in a short period of time can overwhelm the system. Sewers and
treatment works are unable to cope with the large volumes of rainwater entering
the system. Rainwater mixes with sewage in combined sewers and excess mixed
water is discharged into the Thames. If this does not happen quickly enough,
localised flooding occurs. Such sanitary sewer overflow can mean streets becoming
flooded with a mixture of water and sewage, causing a health risk.
In redeveloping the Isle of Dogs and Royal Docks areas of east London during
the late 1980s and early 1990s, the London Docklands Development Corporation
invested in major new drainage infrastructure to manage future sewage
and surface water run-off from proposed developments. Consulting engineer Sir
William Halcrow & Partners designed a system of large diameter tunnels served
by new pumping stations. In the Royal Docks, approximately 16 miles of foul
and surface water drains were built, plus pumping stations at Tidal Basin and
North Woolwich. The Isle of Dogs drainage network is served by a
stormwater pumping station situated in Stewart Street, designed by John Outram
Associates. = Thames Tideway Scheme=
Increasing the carrying capacity of London’s sewerage system has been
debated for some years. Proposals for the 'Thames Tideway' include a wide
diameter storage-and-transfer tunnel, 22 miles long, underneath the riverbed of
the Thames between Hammersmith in the west and Beckton/Crossness in the east,
but as the cost of such a megaproject is likely to be substantial, investment
decisions have been slow in forthcoming. In March 2007 the Mayor of London
announced that the project will proceed with completion expected by 2020.
Because design and construction of such a tunnel will take an estimated 15
years, a shorter-term interim solution has also been developed. This £1.6
billion scheme involves two shorter tunnels and improvements to associated
treatment facilities. Literary or media references
The system plays a large part in English writer Neil Gaiman's 1996 novel
Neverwhere. The system plays a part in Australian
writer Michael Robotham's 2005 novel Lost.
It featured as one of the Seven Wonders of the Industrial World in the BBC
television series of the same name. Eleanor Updale's Montmorency novels are
set against the backdrop of construction of the London sewerage system.
The London sewerage system is also featured in Guitar Hero: Smash Hits as
one of the venues. The London sewerage system plays a large
part in English writer Clare Clark's 2005 novel The Great Stink.
The construction of the London sewer system is central to the plot of Anne
Perry's 2006 novel Dark Assassin, in which the Great Stink is also mentioned.
The title character from Terry Pratchett's Dodger, based on the Artful
Dodger from Oliver Twist, spends much of his time in London's sewers alongside
notable historical figures including Bazalgette.
The sewer system plays a part in Ben Aaronovitch's 2012 novel Whispers Under
Ground. It is the scene of the pursuit of the
villain in Edgar P. Jacobs' 1956 comic book The Yellow "M".
See also Medical Officer of Health for London
Metropolitan Commission of Sewers Tosher
References Notes
External links Tales of the underworld from The
Guardian Wednesday 30 March 2005