1. Civil and Environmental Engineering, Tufts University, Medford, Massachusetts 02155, United States
2. Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ, United Kingdom
3. Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf CH-8600, Switzerland
4. Swiss Tropical and Public Health Institute, Basel CH-4051, Switzerland
5. University of Basel, Basel CH-4055, Switzerland
6. Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States