Geological and hydro-chemical characterisations of groundwater resources in the Wa municipal district

Abstract

Few studies go beyond one or two parameters of groundwater characterisation at a time. This paper uses a multifaceted approach to describe the nature of groundwater beyond water quality, including the physical, environmental, and practical aspects of groundwater prospecting, the health effects, and how these conform to expected standards in global and national contexts. This was achieved by exploring the geological and hydrochemical characterisations of groundwater in the Wa municipality of Ghana. The main objective was to describe the spatial, hydro-geological, and hydro-chemical characteristics of groundwater in the rural areas of the Wa municipality. Using a sequential exploratory mixed research design and a digital elevation model, this study found that groundwater constitutes the main source of safe drinking water for rural and peri-urban communities, geologically dominated by granite and sandstone aquifers. The average transmissivity was 8.88 m2/day, the average hydraulic conductivity was 0.18 m/day, the average aquifer thickness was 56.8 mbgl, and the average borehole water yield was 14.54 L/min. However, there were technological constraints on the ability to prospect water from confined aquifers at sites in the higher parts of the digital elevation model. Also, a lack of water quality tests for some boreholes results in the exposure of users to the effects of fluoride, causing dental fluorosis. The use of ultra-deep hand pump technologies, water quality testing of all boreholes, and artificial groundwater recharge methods for sustainable borehole water yield were recommended.