Statistical analysis of shallow well characteristics as indicators of water quality in parts of Ibadan City, Nigeria

Abstract

The inability of private well-owners to conduct well-water tests is a major obstacle to addressing contamination of water for human consumption in Ibadan city. Shallow well characteristics and their water quality were assessed with the aim of identifying observable characteristics that serve as markers of well water status. Field observation and interviews were employed to assess the features of 100 shallow wells. In addition, physicochemical and bacteriological parameters of water samples from selected wells were analysed. Out of 100 wells, the aggregate score of 60% ranged from high to medium risk. The mean concentrations of manganese, iron, total dissolved solids, pH and bacterial population were outside the WHO permissible limit in more than 50% of the sampled wells. Wells with poor locational characteristics had high turbidity and bacterial population (P < 0.05). A regression model showed that improved structural and maintenance scores of wells will reduce bacterial load in the well water; hence their scores can indicate water quality status.