1. Delft University of Technology, Faculty of Civil Engineering and Earth Sciences, Water Resources Section, Stevinweg 1, 2628CN Delft, The Netherlands; (31) 15‐2787346;
2. Waternet (Amsterdam Water Supply), Sector O&A, Dept. O&P, Vogelenzangseweg 21, 2114 BA Vogelenzang, The Netherlands; (31) 235233569; (31) 6‐20440256;