How much of the Netherlands is affected by the problem regulated by the Hoogheemraadschap van Rijnland?
Flood control in the Netherlands Flood control is an important issue for the Netherlands, as about two thirds of its area is vulnerable to flooding, while the country is among the most densely populated on Earth. Natural sand dunes and constructed dikes, dams, and floodgates provide defense against storm surges from the sea. River dikes prevent flooding from water flowing into the country 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 control boards are the independent local government bodies responsible for maintaining this system.
Leidschendam-Voorburg Leidschendam-Voorburg ] is a municipality in the western Netherlands, in the province of South Holland. The municipality had a population of in , and covers an area of 35.62 km2 of which km2 is water.