Challenges associated with ground water resources development in northern Ghana

Abstract

It is estimated that groundwater contributes about 62 percent of the total water requirement of Ghana. It contributes an average of 67 percent to Northern Ghana’s domestic water needs. The groundwater resources of Northern Ghana are obtained from a variety of hard rock units, comprising basement complex (crystalline) systems and varying Neoproterozoic sedimentary rock types and, therefore, have varying hydrogeological characteristics. Some of the hard crystalline and Neoproterozoic rocks are overlain by a thick argillaceous overburden of high porosity and low permeability characteristics. Groundwater development in these hard rocks is structurally-controlled and successful boreholes are characterised by variable yields, which range from less than 0.2 m³ h^-1 to 500 m³ h^-1 at depths ranging from 40 - 160 m. The hard rock aquifers of Northern Ghana are generally discrete, giving rise to localised flows, thus, making regional aquifer evaluations rather challenging. Even though groundwater constitutes the main water supply sources, its development is fraught with challenges that range from exploration through drilling to water quality issues. These challenges have been noted to be highly related to the nature and characteristics of the underlying geological formations. This paper discusses some of the challenges that have been experienced during the long period of hydrogeological field practices in the northern part of the country.