During the early 19th century the
River Thames was an open sewer, with disastrous consequences for public health in
London, including
cholera epidemics. Proposals to modernise the sewerage system had been made in the early 1700s but the costs of such a project deterred progress. Further proposals followed in 1856, but were again neglected due to the costs. However, after the
Great Stink of 1858,
Parliament realised the urgency of the problem and resolved to create a modern sewerage system. on 15 April 1865 opening Bazalgette's
Crossness Pumping Station Joseph Bazalgette, a
civil engineer and Chief Engineer of the
Metropolitan Board of Works, was given responsibility for the work. The
BBC states, "Bazalgette drove himself to the limits in realising his subterranean dream". He and his colleagues, including
William Haywood, 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 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 of main sewers that, in turn, conveyed the contents of some of smaller local sewers. Construction of the interceptor system required 318 million bricks, of excavated earth and 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. Many sewers north of the Thames feed into the
Northern Outfall Sewer, which transports sewage to
Beckton Sewage Treatment Works. South of the river, the
Southern Outfall Sewer extends to a similar facility at
Crossness. Smaller sewage treatment plants also serve areas further away from central London, such as at
Mogden and
Edmonton. In the late 19th century, William Dibdin, chief chemist for the MBW, conceived the biological
treatment of sewage to oxidize the waste. 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. The sewage works, from west to east, discharging into the tidal Thames in 1950-53 were: ==Modern development needs==