Comprehensive Analysis of the Water Quality of Doab Veisian River in the Western of Iran

The availability of qualified water is essential to preserve the environment and human health. This study was conducted with the aim of evaluating the quantity and quality of river water in different parts of the water consumption. For this purpose, the changes of the surface of the Khorram Abad river at Doab Veisian station during the period of 1998-2016 were investigated and the flow continuity curve was used to estimate the environmental discharge. In order to check water quality in different parts of the river, Schuler's diagram, Wilcox's diagram, Piper's and Durov's diagram and Langier's saturation index were used. In addition, using the stepwise regression method, the effects of pH, HCO3, Cl, SO4, Ca, Mg, Na, K, SAR and TH parameters on TDS were estimated. Based on the results, the environmental discharge was estimated as 4.945 m3/s according to the continuous flow curve method. This amount was equal to 24.64% of the average annual discharge for the Visian Doab River. The water of this river is suitable for drinking and agricultural use in the study area, and based on the Langir saturation index, the water of this river is corrosive for industrial use and the implementation of drip irrigation systems, and treatment should be considered before use. In addition, the type of water in this river was calcium-magnesium type. The results of the regression relationship showed that there is a positive relationship between EC, Ca, Mg, Na, TH and TDS and there is a negative relationship between pH, HCO3, Cl, SO4, K and SAR with TDS, and EC parameter had the greatest effect on TDS.