The Metropolitan Water Board was founded in 1903 to bring the nine private water companies which were supplying water to London under a single public body.
The members of the board were nominated by the various local authorities within its area of supply. A Royal Commission had reported in 1899 on the need for such controls.
The various public water boards and local authority water undertakings in England and Wales were reorganised by the Water Act 1973. 10 large Water Authorities were established based on river basins and catchment areas.
Accordingly, in 1974, the assets of the Metropolitan Water Board passed to the Thames Water Authority governed by a 60 person board, and covering the area from the source of the Thames in Wiltshire to the Thames Estuary.