Three Rivers District

Three Rivers is a local government district in south-west Hertfordshire, England. Its council is based in Rickmansworth. The district borders Hertsmere, Watford, St Albans, Dacorum, Buckinghamshire, and the London boroughs of Hillingdon and Harrow.

Three Rivers District was created on 1 April 1974 under the Local Government Act 1972, covering the whole area of two former districts and most of a third, which were all abolished at the same time:

The new district was named "Three Rivers", referencing the rivers Chess, Colne, and Gade which flow through the district and have their confluence in Rickmansworth, the largest town in the district.

Hertfordshire has a two-tier structure of local government, with the ten district councils (including Three Rivers District Council) providing district-level services, and Hertfordshire County Council providing county-level services. In some areas there is an additional third tier of civil parishes.

Three Rivers District Council carries out a variety of district council functions including:

The council has been under no overall control since a by-election in August 2024, having previously been under Liberal Democrat majority control since 2018. The leaders of the council have been Liberal Democrats (or their predecessors, the SDP–Liberal Alliance) since 1986, including through some periods of minority administrations.

The first election to Three Rivers District Council was held in 1973, initially acting as a shadow authority alongside the outgoing authorities until the new arrangements took effect on 1 April 1974. Political control since 1974 has been as follows:

The leaders of the council since 1986 have been: