1. Chair of Hydrology and River Basin Management, School of Engineering and Design, Technical University of Munich, 80333 Munich, Germany
2. Faculty of Water Resources and Irrigation Engineering, Arba Minch University, Arba Minch P.O. Box 21, Ethiopia
3. U.S. Geological Survey, California Water Science Center, 4165 Spruance Rd., Suite 200, San Diego, CA 92101-0812, USA
4. Faculty of Hydraulic and Water Resources Engineering, Arba Minch University, Arba Minch P.O. Box 21, Ethiopia
5. Earth Knowledge Inc., Tucson, AZ 85751-0743, USA