The Dutch created another smart innovation to deal with water masses while restoring ecosystems. At about 1h Northwest of Amsterdam, near the small community of Kornwerderzand, there is the dyke separating the Wadden Sea from the IJssel sweetwater lake (IJsselmeer).
Experience and research show that the marine ecosystems have changed significantly since the construction of that dyke. The IJssel lake, once having been a shallow bay leading to open waters (back then called called Zuiderzee), gradually transformed into a freshwater lake. Fish migration to and from the open sea was blocked. As one result, fish populations in the IJssel lake area decreased and the natural fish migration patterns of various fish species were altered.
The ingenious solution developed in recen ttimes took the form of a so called “fish migration river” – a water route for the fish to swim again freely from salt to sweetwaters.
Also, the area will be opened for recreational tourism in the next two years. In the meantime, guided tours on site are available on request.
It is definitely an interesting site! Hop eis that with the fish species able to migrate back and forth again, ecosystems will restore and fish populations will grow.
https://www.fishmigratierevier.nl
Guided tours at this moment are organised by It Fryske Gea, here for instance: https://www.vismigratierivier.nl/activiteiten/wandelexcursie/
Although the siite is in Dutch, do not hesitate! Most Dutch speak English mor ethan well enough. Assume that this project simply did not yet have the extra resources to provide a translation of their web contents – but let that not prevent you from joining an excursion.