Meanwhile, around Leiden digging work had started to increase the draining efficiency of the small rivers called the "Zyl" and "Does", which would carry the overflow towards the Haarlem Lake and the Kagerplassen.Website of the Hoogheemraadschap van Rijnland 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 a collaborating group of officials called heemraden who oversaw the dikes along the IJ river at Amsterdam and in the Rhine 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 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) began to be used around 1400, when the water district borders differed greatly from the borders of the nearby municipalities.The success of the Zijl and Does river outlets was not enough to avoid heavy floods, and in 1248, a heavy storm again caused a lot of damage, so a dam was built at Spaarndam. This caused a fierce dispute with Haarlem, since that city was dependent on free access for ships to the IJ. The dispute was solved by building an extra sluice in 1253 for ships that could pass when the water levels on both sides of the sluice were the same.De Kleine Haarlemmer sluis on the website of the North Holland Archives To emphasize that control over the sluices and dikes at Spaarndam were under the jurisdiction of the Hoogheemraadschap van Rijnland, Count Willem II granted the privileges to levy a toll on ships to the Dike wardens, and not to the city of Haarlem. It is this document from 1255 that is referred to in the painting by Caesar van Everdingen in 1654. From that point on, the heemraden at Spaarndam were called the heemraden van Rijnland.
