Hydro-Climatic Variability of the Ogooue Watershed in Lambaréné

Abstract

Located in the center-west of Gabon, the city of Lambaréné is frequently affected by floods which cause material, economic and health damage. This scientific contribution presents the preliminary results of a larger study on the risks of flooding in the Ogooué basin in Lambaréné. The analysis of the flows (1959-1989), water levels (2000-2010) and rainfall common to both time periods shows that the most favorable period for floods corresponds, among others, to the months of October and November that record abundant precipitation, at the origin of the main hydrological peaks of November-December. In general, there is an evolution in phase between the pluviometric positive anomalies, flows and water heights likely to cause overflows of the waters of the Ogooué. Key words: Gabon, rainfall, water level, variability