Investigation the water quality of Khersan 2 dam underground using multivariate statistical analysis.

In this study we investigated the water quality of Khersan 2 dam, Iran, using   multivariate statistical methods. For this purpose, The monthly data of the rivers water quality parameters including electrical conductivity (EC), PH, Hco3, Ca, Mg, K, Na, Cl, CaCo3 and TDS was collected., the Principal Component Analysis (PCA) method is used to identify the main quality parameters that play more important role in changing the water quality of the Khersan 2 dam reservoir. Results of PCA analysis indicated that all the selected chemical and physical parameters of Khersan 2 dam were of high importance. Based on the studies, three factors were identified as important factors that have the greatest role in determination the variance of the data. The first factor, which has about half the impact on water quality with a percentage 55.28% of the total variance, includes Cl, Na, Mg, Ca, EC and TDS, which is completely related to the water quality and the nature of the area. The second factor consists of HCo3 and CaCo3, and the third factor is K and PH. The second and third factors are 15.14% and 10.25% of the total variance, respectively. The second and third factors are affected by the dissolution of Asmari limestone in the study area. In addition, the comparison of the chemical analysis results of the Khersan 2 dam reservoir water with the national standards and the World Health Organization has been carried out.