Groundwater Contamination and Public Health Risks in Eastern Ghana: Evidence for Strengthening Water Safety in Sub-Saharan Africa

Groundwater remains a vital source of drinking water for many communities in Ghana, yet its safety is increasingly threatened by human activities and natural processes. This study assessed the microbiological and physicochemical quality of groundwater from boreholes (BH) and hand-dug wells (HDW) in eight communities in the Eastern region of Ghana, and results were compared against the World Health Organization (WHO) and Ghana Standards (GS 175-1) for drinking water. Water samples were analysed for turbidity, pH, alkalinity, electrical conductivity (EC), total dissolved solids (TDS), nitrate, sulphate, and phosphate using APHA standard protocols, while Escherichia coli and total coliforms were quantified by membrane filtration. The majority of the physicochemical parameters were within the safe values, but the alkalinity values were above 200 mg/L in some wells, and the level of nitrates in some of the HDW’s were more than 50mg/L, which is an indicator of agricultural inputs and sanitation leakage. Some HDWs were also reported to have phosphate levels exceeding the recommended safe limit of 0.1 mg/L, and this indicates that the water is being impacted by human activity. Microbial contamination was a common problem; E. coli was found in half of the water samples, and total coliform levels were higher in over 64% of them, including some drilled boreholes. The worst cases of microbial contamination were in the hand-dug wells at Akwadum and Effiduase. The results show that while the groundwater in the area is generally stable chemically, the presence of harmful microbes, especially in shallow, uncovered wells, poses serious health risks. These risks can be further exacerbated by climate change that leads to a greater amount of flooding, change in patterns of recharge and greater transport of contaminants to shallow aquifers. There is therefore a great need to enhance the protection of well sites, enhance sanitation, and set up routine water quality tests as a way of ensuring that there is a safe and long-term supply of drinking water.