1. Pontificia Universidad Javeriana; Cra. 7 No 40-62 Bogotá D.C. Colombia
2. Rivers, Ports, Waterways and Dredging Works Section, Faculty of Civil Engineering and Geosciences; Delft University of Technology; PO Box 5048 2600 GA Delft The Netherlands
3. Department of Water Engineering; UNESCO-IHE; PO Box 3015 2601 DA Delft The Netherlands
4. Hydrology and Quantitative Water Management, Department of Environmental Sciences; Wageningen University; Droevendaalsesteeg 4 6708 PB Wageningen The Netherlands
5. Institute for Biodiversity and Ecosystem Dynamics; University of Amsterdam; PO Box 94248 1090 GE Amsterdam The Netherlands