Volkerak

It is part of the Rhine–Meuse–Scheldt delta, and is situated between the island Goeree-Overflakkee to the north-west and the Dutch mainland to the south and east.

Before 1987, it was a tidal river open to the North Sea, but it was closed off as part of the Delta Works; it is now a fresh water lake.

On the eastern end are the Volkerak Locks (Volkeraksluizen) connecting it to the Hollands Diep.

Finally, the Scheldt–Rhine Canal connects it to the port of Antwerp and thus the North Sea, providing access for ocean-going vessels.

Due to the low supply of fresh water to the now-enclosed Volkerak, and runoff of agricultural nutrients, the lake suffers from algal bloom throughout the summer,[3] and swimming is prohibited.