Since its foundation, the Thames has been at the heart of London. Many tributaries flow into it and over time these have changed from sources of water to open sewers and sources of disease.
As the city developed from a cluster of villages, many of the existing rivers were buried or canalized: see subterranean rivers of London.
The rivers failed to carry the sewage of the growing metropolis. The resulting health crisis led to the creation in the late nineteenth century of the London sewerage system, designed by Joseph Bazalgette, one of the first modern sewer systems in the world.
The Thames Water Ring Main is a notable modern piece of large-scale water supply infrastructure, comprising 80km of wide-bore water-carrying tunnels.
