Quality Assessment of Takab Sarugh River Right Branch by Wilcox Index and Its Zoning Using Geographical Information System, 2011

Background and Using Water Quality Indices are necessary for monitoring the quality of water in various applications، including agriculture. This study aimed to assess the quality of Takab Sarugh river right branch by WILCOX index. In this cross sectional study some quality parameters including water temperature، sodium، calcium، magnesium، total hardness، pH، electrical conductivity، sodium adsorption rate، total dissolved solids were measured monthly in five stations located along the river during spring and summer 2011. EC and SAR levels changes toward river discharge were determined for each station. Also، quality of water in each station was determined using WILCOX diagram and geographical information system. The maximum SAR and EC values (1. 3 and 1368 s/cmµ، respectively) were found in station C in September، while the lowest values were seen in station A in May. Results showed that the concentration of parameters decreased when the river flow increased. Based on SAR index the quality of water was in class S1 (low alkaline risk) and the EC was fluctuating between C1، C2، C3 classes (salinity risk: low، medium، and high، respectively). The results showed that quality class of river water in low water season decreased into moderate class from good and excellent classes. Probably sedimentary rocks، limestone springs and effluent of a gold extraction factory located in the studied area resulted in declining quality of water.