The Southern Outfall Sewer is a major sanitary sewer taking sewage from the southern area of central London to Crossness in south-east London. Flows from three interceptory sewers combine at Greenwich pumping station 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 Great Stink of 1858.