Spatial evaluation of groundwater quality using factor analysis and geostatistical Kriging algorithm: a case study of Ibadan Metropolis, Nigeria

Abstract

Necessity calls for the environmental aspects of groundwater to be evaluated and properly managed based on the observed spatial distribution with respect to quality, as it contributes to a significant portion of average water usage globally. Variations in groundwater quality in the Ibadan Metropolis might be a result of physical and chemical trends in the region leading to a decline in quality. The study was geared towards the spatial evaluation of groundwater quality using factor analysis and the Kriging algorithm. The parameters examined include pH, electrical conductivity, total dissolved solids, carbonates, chloride, nitrate, sulphate, calcium, sodium, magnesium, and potassium, which were sampled and analysed from the existing municipal deep wells in the Ibadan Metropolitan area; and distribution maps of each parameter were created using a geostatistical approach. Factor analysis examined the relationship between human activities and concentration levels. Semi-variograms were tested to ascertain the best-fitted model accuracy measures, average standard error, root mean square error, and root mean square error standardised. The groundwater index was calculated to ascertain the drinkability of the water in the study area. Overall, the result shows that the groundwater in the study area is suitable for consumption; drinking, and other uses. Kriging is a suitable assessment tool for modelling environmental parameters.