1. Berliner Wasserbetriebe, Neue Juedenstr. 1, 10179 Berlin, Germany
2. RWTH Aachen University, Institute of Environmental Engineering, Mies-van-der-Rohe-Str. 1, 52074 Aachen, Germany
3. School of Life Sciences, Institute for Ecopreneurship, University of Applied Sciences and Arts Northwestern Switzerland, Hofackerstrasse 40, 4132 Muttenz, Switzerland