Historical Evolution of Epidemiology
During the 19th century, drinking water was supplied to houses by private companies via a network of pipes. There was competition between the water companies, resulting in overlap between the areas supplied by the different companies.
Toilets were widely introduced in London between 1830 and 1850: main sewers were introduced in the 1840s. The sewers emptied into the River Thames.
During the 1848-9 cholera epidemic, mortality from cholera was particularly high in the districts supplied by two particular water companies, the Southwark & Vauxhall and the Lambeth companies, both of which took water direct from the River Thames where it flowed through London.
Click below to view part of the original map of this area, including an area where both companies supplied water. The green area was served by the Southwark and Vauxhall company, the pink area by the Lambeth company, and the grey area in between is where the two companies' pipes were intermingled.Map