Comparative analysis of borehole water quality and heavy metal pollution in Etinan and Uyo local government areas of Akwa Ibom State, Nigeria

This study assessed and compared the water quality of selected boreholes in Uyo and Etinan Local Government Areas of Akwa Ibom State, Nigeria, using the Water Quality Index (WQI) and Heavy Metal Pollution Index (HPI). Borehole water samples were collected from five locations in each area and analysed for physicochemical and heavy metal parameters using standard analytical procedures. The WQI was computed based on eight key parameters, while the HPI was calculated for cadmium (Cd), iron (Fe), lead (Pb), and copper (Cu). Results revealed that the WQI values ranged from 113.62 to 263.04, classifying the water as unsuitable for drinking according to the WHO standards. The low pH values indicated acidity, while elevated Total Dissolved Solids (TDS) and Electrical Conductivity (EC) in some Uyo samples suggested anthropogenic influence. In contrast, Etinan samples exhibited relatively better quality. The HPI values ranged between 23.64 and 646.59, significantly above the critical threshold of 100, indicating serious heavy metal contamination in some sites. Overall, the study concludes that although heavy metal pollution is low, the borehole water from both Local Government Areas requires proper treatment before domestic use. Continuous monitoring and sustainable management strategies are recommended to safeguard groundwater quality in the region.