Study of the Drinkability of Groundwater on the Island of MAR in Senegal

Abstract

For a long time, the supply of drinking water to the island of Mar was ensured by drilling and wells. The advance of the salt wedge led the populations to stop the exploitation of the drilling due to the accentuation of the salinity of the water characterized by high fluorine content. The marine environment and the rainfall deficit of recent decades as well as population growth have highlighted the sensitivity of this resource. The objective of this article is to study the drinkability of the water supplied by the drilling and the wells of the island of Mar. for this, water samples were taken in the Continental Terminal and their analysis made in situ or in the laboratory. Data processing was done by using Surfer 11 and ArcGIS software. It was emerged from this study that the drop in the piezometric level caused an entry of salt water. The mineralization of the water follows a decreasing trend from areas with marine influence inland. Groundwater in certain areas is generally of good quality with some sources of pollution linked to salinity but also to high levels of nitrate, chloride and fluorine. The island of Mar being confronted with a problem of drinkability of groundwater, the alternative would be to proceed to a transfer of better quality water from nearby areas after a hydrogeological and physico-chemical study of these waters in relation to their fitness for consumption.