A Comparison between Weighted Arithmetic and Canadian Methods for the Drinking Water Quality Index, Al-Abbasia River, Najaf, Iraq

Abstract

In this study, eight samples were analyzed along Al-Abbasia River, where the Water Quality Index and pollution or changes in water quality were studied. The Water Quality Index is a useful and rapid technique for evaluating the quality of any water source. The samples were taken along Al-Abbasia River and on the area basis which influence the river. The physical and chemical parameters (pH, Turbidity, Alkalinity, Electrical Conductivity, Total Disollved Solids, Total Hardness, Ca2+, Total Suspended Solids, Na+, Cl-, K+, SO42-, Mg2+) were evaluated in this study using the Weighted Arithmetic Water Quality Index and Canadian Council of Ministers of the Environment Water Quality Index methods which shows the extent of pollution. According to Weighted Arithmetic Water Quality Index, the water quality is classified as a poor except for the second sample, where it was classified as a Very poor (according to the standards of the WHO), while according to Canadian Council of Ministers of the Environment Water Quality Index method, the water of Al-Abbasia river was often classified as a Good, except for the second and forth samples they were classified Fair. This study showed that the main cause of the deterioration of water quality in Al-Abbasia River is the direct discharge of sewage, human activity and harmful residues of pesticides and materials which used in agriculture.