Water levels in this area are tightly managed by pumps. Also in normal times they pump water in and out to keep a specific level. All of this is lower than the

Water levels in this area are tightly managed by pumps. Also in normal times they pump water in and out to keep a specific level. All of this is lower than the Amsterdamrijnkanaal, so without pumps it would flood, water doesn't naturally flow out of this place only from evaporation.