HYDRO-SEDIMENTARY CHARACTERIZATION AND MOUTH MIGRATION PROCESS OF BANDAMA’S RIVER (CÔTE D’IVOIRE).

The morphology of Bandama’s mouth varies continuously depending tides, storms, river flow and seasons. This morphological variation is accompanied by the migration of the channel toward the west destroying progressively the historic town of Grand-Lahou. Seasonal measurements of salinity, make possible to schematize the evolution of the tide and the salinity in the estuary. The analysis of air-photography and satellite picture make possible to track the migration and morphological evolution of the mouth. We distinguish essentially two types of morphologies: In low water period, is built a littoral arrow that extends the bar from the East to the West. The channel width is very reduced. The west bank remains almost stable. In flood period, the west bank of the channel is attacked simultaneously by waves and river flow destroying thisbar thus,That causes the channel migration westward. Between 1957 and 2016, the mouth of Bandama’s river has migrated about 1800 m with an average speed of 30.5m / year or 2.5 m /month.Littoral drift, caused by the obliquity of the swell in relation to the shore. Erosion spreading of this bar is the result of the combination of these factors in additional to the entropic effects.