Dutch water boards (Dutch: waterschappen or hoogheemraadschappen) are regional government bodies charged with managing water barriers, waterways, water levels, water quality and sewage treatment in their respective regions. These regional water authorities are among the oldest forms of local government in the Netherlands, some of them having been founded in the 13th century.
Around 26 percent of the area of the Netherlands is at or below sea level and several branches of the Rhine-Meuse-Scheldt delta run through this relatively small country. Historically there always was a good deal of coastal and river flooding. Flood control in the Netherlands is a national priority, since about two thirds of the country is vulnerable to flooding, while at the same time it is one of the most densely populated areas on Earth. Natural sand dunes and man-made dikes, dams and floodgates provide defense against storm surges from the sea. River dikes prevent flooding of land by the major rivers Rhine and Meuse, while a complicated system of drainage ditches, canals and pumping stations (historically: windmills) keep the low-lying parts dry for habitation and agriculture. Water boards are independent local government bodies responsible for maintaining this system.
An Unie van Waterschappen (the association of Dutch regional water authorities, referring to itself as 'Dutch Water Authorities') promotes the interests of Dutch water boards at a national and international level. 23 of the water boards are members of this association. The Unie van Waterschappen acts collaboratively with other appropriate bodies or institutions to pursue the Association's objectives, including association with other European organisations through membership of the EUWMA, (European Union of Water Management Associations).