How the Sponge City becomes a supplementary water supply infrastructure

While in today's Sponge Cities flood control works effectively, the sponge-based rainwater harvesting is associated with substantial challenges. In addition to water management, the pollution of collected stormwater counts as one of the major barriers for urban water augmentation. The aim of this communication is to outline how this constraint can be overcome and how the water service portfolio of the Sponge City can successfully undergo feasible expansion considering technical and also economic aspects. Innovative engineered solutions for a sponge-based rainwater harvesting are the key to an adaptive and flexible water supply infrastructure for Sponge Cities especially to preserve its manifold urban water and life quality services. The complementary water service, emerged from the Sponge City, can provide an imperative contribution to compensate the high capital investments and to cover the operation and maintenance costs. This enables a tremendous funding opportunities that can be invested for the preservation of the blue-green future city. Moreover, this would offer a feasible way of urban water service development over the negative impacts caused by climate change. © 2021