Seismic imaging to help understand and manage water quality in coastal Benin, West Africa

The coastal city of Cotonou in Benin, West Africa relies on the Godomey aquifer for fresh drinking water. Increased pumping of the aquifer to accommodate rapid population growth has led to saltwater intrusion into the aquifer. Previous work shows a groundwater divide between the aquifer and the Atlantic coast suggesting the source of salinity is nearby Lake Nokoú, a large shallow lake with high salinity levels during the dry season. We use shallow seismic reflection imaging to characterize the lithology of the Godomey aquifer with the goal of using this information to improve regional water management strategies. The purpose of this paper is to present our initial data and interpretations collected from the first of two field seasons for the project.