Groundwater Quality Ranking of Sarab Plain for Drinking Purpose Using Entropy Method

In recent years, the new methods for assessment of groundwater resources quality have been developed extensively. In this research, the application of Entropy Theory to evaluate groundwater quality for drinking purposes is shown. In rural regions, the groundwater resources are the main source of drinking water. Also, the source of drinking water in Sarab plain is groundwater resources. The Entropy method was used, in order to prevent the individual judgments on determination weight of the parameters used in Water Quality Index Method. In this study, for evaluating Sarab Plain groundwater quality for drinking purposes through entropy weighted method, 12 groundwater parameters affecting the quality of drinking water, including bicarbonate, sulphate, chloride, calcium, magnesium, sodium, potassium, lithium, fluoride, nitrate, sillies and electrical conductivity, were used. Results showed that chloride had the highest impact on water quality of Sarab plain aquifers. Potassium, sodium and nitrate are the most unstable parameters among the studied parameters. The results showed 53 and 18 percent of groundwater samples were classified in group one and two respectively.