Soft Paths in Wastewater Management – The Pros and Cons of Urine Source Separation

This is the authors' abstract. We don't add key points for this paper.

Although our water-borne urban wastewater system is successful, it has drawbacks in industrialized and developing countries alike, particularly in arid regions. It is inflexible and often inefficient. Of late, source control measures are being postulated as a paradigm change. In the Swiss transdisciplinary project Novaquatis, urine source separation, or NoMix technology, was studied. We compare NoMix technology with central wastewater treatment. Separate collection of urine has the potential to eliminate 70 to 80 percent of nitrogen from wastewater, 15 to 50 percent of phosphorus, and at least 50 percent of human pharmaceuticals. Hence, NoMix technology can contribute substantially in the reduction of eutrophication of marine ecosystems near fast-growing cities. We discuss the shortcomings of using sewage sludge or urine as fertilizers in agriculture – concerning pharmaceuticals, we also consider the societal perspective. Furthermore, NoMix technology introduces flexibility to waste-water management, important especially in light of growing uncertainties with respect to population development and climate change.