1. Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia
2. Addis Ababa Institute of Technology, Addis Ababa University, Addis Ababa, Ethiopia
3. Department of Civil, Environmental and Natural Resources Engineering, Division of Geosciences and Environmental Engineering, Luleå University of Technology, 97187 Luleå, Sweden
4. Civil and Environmental Engineering Department, University of Connecticut, Storrs, USA
5. Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA