1. Cranfield Water Science Institute, School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK
2. Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, Garching, Germany
3. Severn Trent Water, 2 St John's Street, Coventry, CV1 2LZ, UK
4. Scottish Water, Juniper House, Heriot Watt Research Park, Edinburgh, EH14 4AP, UK