In 1965, the Dee and Clwyd River Authority was constituted, superseding the numerous earlier authorities concerned with the navigation of the Dee Estuary and the drainage of low-lying coastal and estuarial land. The construction of a navigable cut from Chester to Connah's Quay had been empowered by an Act of 1732, to replace the old deep-water channel to the north of the estuary, and in 1740 the River Dee Company was created to maintain the navigation. The Dee Conservancy Act 1889 established the Dee Conservancy Board, taking over the Company's functions. In 1938, the Conservancy Board officially came to an end. An Act of 1794 constituted the Rhuddlan Marsh Embankment Trust; the coasts and the banks of the river were embanked. In 1921, the River Clwyd Drainage Board took over their powers, and in turn passed them to the Dee and Clwyd River Authority. The enclosure of Rhyl Marsh was considered in 1831, and a committee was set up. In 1853, the Rhyl Improvement Commissioners became responsible for the Rhyl Marsh Committee. The River Dee Drainage Board was established under the Land Drainage Acts of 1861 and 1918 and the River Dee Drainage Order of 1922. This Board was abolished in 1934, and replaced by the River Dee Internal Drainage Board. The River Dee Catchment Board was established in 1930 to maintain main water courses and land drainage. In 1946, its powers were wholly transferred to the Rivers Dee and Clwyd Catchment Board, established by the Ministry of Agriculture and Fisheries. In 1950, together with the Rivers Dee and Clwyd Fishery Board, it became the Dee and Clwyd River Board, under the River Boards Act, 1948. The Rivers Clwyd and Elwy Fishery Board was created in 1894; in 1949, it was amalgamated with the River Dee Fishery Board and the River Dee Joint Committee to form the Rivers Dee and Clwyd Fishery Board. The Hawarden Embankment Trust was active from 1853 to 1930. The Central Flintshire Water Board held its first meeting in 1964. The West Denbighshire and West Flintshire Water Board held its first meeting in 1965. From 1974 until 1979, the Welsh National Water Development Authority, later the Welsh Water Authority, comprised three different divisions of River, Water, and Sewage. The Hawarden and District Waterworks Company was incorporated in 1883, but from 1964 its undertakings were under the Central Flintshire Water Board.
