Assessment of groundwater quality using water quality index (WQI) and multivariate statistical analysis in Amman-Zarqa area/Jordan

Abstract

The evaluation of the relevant physical and chemical parameters of 246 samples of groundwater quality from the Amman-Zarqa area showed that most of the parameter values exceeded the maximum permissible limits for drinking according to the Jordanian Institute of Standards and Meteorology. Based on the hydrochemical analysis, the water can be classified into four distinct water types using the Piper diagram, whereas, the hydrogeochemical process that affects the groundwater parameters is the dissolution or mixing process as indicated by the Durov diagram. The correlation between the different parameters showed that the basic ionic composition of the water samples is directly influenced by physicochemical parameters and anthropogenic activities. Additionally, factor analysis has been conducted and three factors were extracted. The three factors account for the ‘salinity’, ‘hardness’, and ‘pH’ properties and were named accordingly. These three factors accounted for 78.5% of the total variance of the data composition. Furthermore, a hierarchical cluster analysis of the 246 samples was carried out and three groups were obtained to verify the factor analysis results. Based on water quality index values, 12% of the groundwater samples can be described as ‘excellent’ and 53% of ‘good’ quality. The remaining 35% of the samples are of ‘fair’ and ‘poor’ qualities. These findings are important in understanding the sustainability of groundwater for drinking purposes in the study area.