1. Pennine Water Group, Department of Civil and Structural Engineering, University of Sheffield, Mappin Street, Sheffield,
2. URGC–Hydrologie Urbaine, INSA de LYON, 69621 Villeurbanne Cedex, France
3. Aalborg University, Section of Environmental Engineering, Institute of Life Sciences, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark