A Dutch municipality with more than 200.000 inhabitants has a sustainable future vision is a place with plenty of opportunities to make the benefits of the circular economy visible and to achieve impact with residual flows (waste).
One of the opportunities concerns a lake, which over the years has become very shallow. A shallow lake is unfavorable for the survival of different species of animals and plants, thus for the biodiversity. Deepening (dredging) the lake is an option. However, just dredging is expensive and not profitable just for better biodiversity.
That is why the municipality wants to dredge the sludge to make circular products. The sludge is special because it is clean, which is not very common. Therefore, it is suited for making circular products. The possible end products could be for example bricks or an exfoliating cream. Other additional benefits of this deepening are: less growth of water plants, lake can be used to heat / cool of nearby buildings and uplifting bio diversity of the lake. This fits well with the circular idea of the municipality.