Belfast City and District Water Commissioners

The Belfast Water Commissioners was a public body in Ireland and later Northern Ireland, established by the Belfast Water Act 1840, to improve the supply of water to the expanding town, later city, of Belfast. By 1852, the town was suffering a shortfall in supply of almost one million gallons per day. In 1889, the body's name was changed to Belfast City and District Water Commissioners in recognition of the expanding boundaries of Belfast and resulting increased demand for water. Belfast officially became a city in 1888.

Major infrastructure completed for the Belfast City and District Water Commissioners includes the Mourne Conduit, the Mourne Wall, Silent Valley Reservoir, the Binnian Tunnel and Ben Crom Reservoir.

The water commissioners' responsibilities were transferred to the Department of the Environment's Water Executive in 1974 and are now managed by Northern Ireland Water.