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.

The first steps towards a formal method of dike management were taken in the 12th century when the Oude Rijn river silted shut at Katwijk. Even though the Lek river had already superseded the Oude Rijn as the most important means of transport and water management, the area around Leiden suffered dramatically from storm flooding. To combat this problem, the local nobility of Leiden decided to build a dam at Zwadenburg, now called Zwammerdam. This of course only moved the problem eastwards, towards Utrecht, where they complained to the German emperor Barbarossa. In 1165, he decided in favor of Utrecht and the dam was turned into a sluice. Meanwhile, work had already started on digging to increase the efficiency of the small rivers called the "Zyl" and "Does", which would carry the overflow towards the Haarlem Lake and the Kagerplassen. This ambitious project was the result of 15 neighborhoods working together towards a common goal. By 1255, according to the oldest dated document in the Rijnland archives, there was already a group of officials called heemraden who oversaw the dikes along the IJ and at Zwammerdam. Their privileges were described in this document that was given to the dike warden of the area between Wassenaar, the Zwammerdam, and Spaarndam. At that time Rijnland was just one of the many water districts within the area. Each district had a bailiff, and it was the bailiff who was put in charge of dike maintenance. The term Dijkgraaf (official) only began to be used around 1400, when the water district borders differed greatly from the borders of the nearby municipalities.

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