Internal drainage board

An internal drainage board (IDB) is a type of operating authority which is established in areas of special drainage need in England and Wales with permissive powers to undertake work to secure clean water drainage and water level management within drainage districts. The area of an IDB is not determined by county or metropolitan council boundaries, but by water catchment areas within a given region. IDBs are geographically concentrated in the Broads, Fens in East Anglia and Lincolnshire, Somerset Levels and Yorkshire. In comparison with public bodies in other countries, IDBs are most similar to the Waterschappen of the Netherlands, Consorzi di bonifica e irrigazione of Italy, of Flanders and Northern France and watershed districts of Minnesota, United States.

Much of their work involves the maintenance of rivers, drainage channels (rhynes), ordinary watercourses, pumping stations and other critical infrastructure, facilitating drainage of new developments, the ecological conservation and enhancement of watercourses, monitoring and advising on planning applications and making sure that any development is carried out in line with legislation (NPPF). IDBs are not responsible for watercourses designated as main rivers within their drainage districts; the supervision of these watercourses is undertaken by the Environment Agency.

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