Sustainable rainwater management in the Emscher river catchment area.

The wastewater management system of the Emscher region is currently being radically restructured. The receiving waters currently surviving as open sewers are to be freed of their wastewater burden and reconstituted to a state as natural as possible, while the wastewater is to be routed underground to the treatment plants. Great importance is attached to the most natural possible rainwater management, in order to buffer extreme run-off situations in the watercourses and to minimize the costs for residential-area water management engineering. Rethinking, which in many cases percolates through only slowly, is necessary in many respects for this purpose. A contest has been set up in the Emscher catchment area in order to accelerate this in the existing residential areas. Seepage, decentralized retention, disconnection and discharge into bodies of water and watercourses have been financially supported. The results are presented and the further procedure deriving from them discussed.