The landschape park Duisburg-Nord in Germany’s Ruhr area was created in the 1990s as one of about 100 projects that were implemented in the course of ten years in the framework of the ‘Internationale Bauausstellung (IBA) Emscherpark’. The IBA-Emscherpark was created in order to give a new ecological, economic, social and cultural impulse to the old industrial Ruhr area by means of these restructuring projects. The blue thread through this restructuring project was the Emscher river, which had been used as an open sewer until the 1990s. Due to mining activities and subsidence, underground sewage could not be created.