How much of the Netherlands is affected by the problem regulated by the Hoogheemraadschap van Rijnland?
Hoogheemraadschap van Rijnland The Hoogheemraadschap van Rijnland is the oldest water board of the Netherlands, having received its first commission to protect the land from flooding back in 1248 from William II of Holland. It conducts water control activities in the general area known as Rijnland. The Netherlands has 27 Waterboards or "Waterschappen" acting independently from the National government administration to manage the continuing Dutch struggle against water.
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.