1. CSIR Water Research Institute, P.O. Box AH 38, Achimota, Ghana; Environmental Science Department, University of Ghana, Legon, Ghana; UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands; West Africa Office, International Water Management Institute, Accra, Ghana; and Regional Bureau for Science for Asia and Pacific, UNESCO Jakarta Office, JI. Galuh II, Kebayoran Baru, Jakarta 12110, Indonesia