The Thames Water Authority was one of ten regional water authorities created in the UK on 1 April 1974 under the provisions of the Water Act 1973 to bring together all the water management functions of the region in one public body.

Predecessors

The bodies subsumed by the Thames Water Authority included the Metropolitan Water Board, the Thames Conservancy, the Lee Conservancy Catchment Board and parts of the Essex and Kent River authorities. It also took over water and sewage responsibility from the following water suppliers in the Thames catchment:

Dissolution

In 1989 the Thames Water Authority was partly privatised, under the provisions of the Water Act 1989 with the water and sewage responsibilities transferring to the newly established publicly quoted company of Thames Water, and the regulatory, land drainage and navigation responsibilities transferring to the newly created National Rivers Authority which later became the Environment Agency.