Southern Outfall Sewer

The Southern Outfall Sewer is a major sewer taking sewage from the southern area of central London to Crossness in south-east London. Flows from three interceptory sewers combine at Deptford and then run under Greenwich, Woolwich, Plumstead and across Erith marshes. The Outfall Sewer was designed by Joseph Bazalgette after an outbreak of cholera in 1853 and "The Big Stink" of 1858. Work started on the sewer in 1860 and it was finally opened on April 4th, 1865 by H.R.H. the Prince of Wales.
Until this time, central London's drains were built primarily to cope with rain water, and the growing use of flush toilets frequently meant these became overloaded, flushing mud, shingle, sewage and industrial effluent into the River Thames. Bazalgette's London sewerage system project included the construction of intercepting sewers north and south of the Thames; the Northern Outfall Sewer diverts flows away from the Thames north of the river.

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