The Netherlands drinks Belgian ... water.
This weir is located on the Isabellarigool, about 200 meters upstream from the mouth of the Leopold Canal. The Isabellarigool is a watercourse to which surface water from the sandy woodland south of the Graaf Jansdijk drains, both from the Isabellapolder and from the Zwarte Sluispolder. This water is fresh, in contrast to the brackish surface water of the polders that drains into the Leopold Canal. This weir ensures that the two types of water do not come into direct contact with each other. Fresh water that is not pumped up from the Isabellarigool runs over the weir to the brackish Leopold Canal and is pumped down towards the Netherlands via the Isabellagemaal.
The fresh water is suitable as a basis for drinking water production and industrial water preparation. The saline polder road is not eligible for this because of the high cost price and complexity of industrial desalination processes.
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