Dredging sludge has negative connotations but the Marker Wadden shows that the natural and economic value of dredged material is underestimated.
Sludge, silt and mud are useful raw materials and building materials. They can be used for upgrading soils, raising dikes, nature development or land reclamation.
So the spotlights at the Innovation Expo in Amsterdam today will be on the Marker Wadden: a unique ecosystem that will boost biodiversity, improve water quality, and create space for leisure activities and scientific research.
The Markermeer is one of the largest freshwater lakes in Western Europe. The ecology in the lake has declined severely since the creation of the IJsselmeer lake. By building islands, marshes and mud flats in the lake, the Dutch Society for the Preservation of Nature (Natuurmonumenten) and the Dutch government are working together on restoring natural values.
That involves using the sludge and clay present in the lake. After the construction of a ten-hectare trial island in 2014, work began in the spring of 2016 on the creation of 600 hectares of marsh.
A lot of dredging goes on throughout the world. The dredged material from many projects could also be used for land reclamation elsewhere. This is expected to result in major cost savings in the long term.
So if it turns out that the Marker Wadden can be successful using dredging for nature, the knowledge acquired about building with sediment in freshwater systems and, in the future, in salt lakes will have excellent export potential. That also implies acquiring an understanding of regulations and earning models.
That is why all the knowledge acquired in this project about building with sediment will be anchored in a fundamental and applied knowledge and innovation program.