Quality Assessment of Borehole Water in Southern Taraba State: Takum and Ussa LGAs

Abstract: Groundwater remains the primary source of potable water for many rural and peri-urban communities in Nigeria; however, its quality is increasingly threatened by both natural processes and anthropogenic activities. This study presents a comprehensive assessment of borehole water quality in Takum and Ussa Local Government Areas of the Southern Senatorial Zone of Taraba State, Nigeria, integrating physical, chemical, bacteriological parameters, and the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI). Borehole water samples were analyzed using standard methods and results were compared with World Health Organization (WHO) drinking-water guidelines. Physical parameters such as pH, electrical conductivity, total dissolved solids, turbidity, colour, alkalinity, and hardness were largely within permissible limits, indicating generally favorable hydrochemical conditions. Most chemical parameters, including major ions and heavy metals, were also within guideline limits; however, elevated concentrations of phenol and chlorine dioxide were observed in both locations, raising concerns about chemical toxicity. Bacteriological analysis revealed significant contamination, with total coliforms and Escherichia coli exceeding WHO zero-tolerance limits, indicating fecal pollution and compromised sanitary integrity of boreholes. Despite these bacteriological exceedances, CCME WQI values classified groundwater in Takum (84.73%) and Ussa (84.63%) as "Good," highlighting a critical discrepancy between index-based assessments and direct microbial risk. The findings demonstrate that borehole water in Takum and Ussa is chemically acceptable but microbiologically unsafe for direct consumption without treatment. This study provides evidence-based justification for targeted public health intervention, routine microbial monitoring, and improved sanitation practices in the study area.