Integrated assessment of groundwater quality for sustainable groundwater management in the Fanteakwa District, Ghana

Groundwater in the Fanteakwa District was appraised for its potability and suitability for irrigation using hydrogeochemical, geospatial and statistical techniques. The results revealed groundwater chemistry is characterized by high concentrations of sodium and bicarbonate ions, largely resulting from the disintegration and chemical dissolution of silicate and carbonate minerals linked to the Oti-Pendjari Group lithologies. Two dominant groundwater facies were noted: Na-HCO3-Cl, accounting for 21.62% of the boreholes in the Fanteakwa District, and the other being Na-Mg-HCO3 (10.81%). Geochemical processes including weathering, mineral dissolution, and ion exchange are the key mechanisms governing groundwater chemistry. Anthropogenic influences, particularly the application of fertilizers on arable lands, were also identified as contributing factors to groundwater composition. According to the geochemical modelling, groundwater remains undersaturated with respect to aragonite, calcite, gypsum, dolomite, halite, and fluorite. Assessment of groundwater potability revealed that the water is suitable for human consumption. While groundwater is largely appropriate for irrigation use, high values of sodium percentage and Kelly index in certain locations suggest that it may not be suitable for irrigation without prior treatment. Therefore, groundwater in the areas with high values of these irrigation water quality indices requires remediation or treatment prior to usage for irrigation purposes.