Evaluation of river- aquifer interaction using physicochemical parameters, Case study: the north part of Dezful - Andimeshk district

Determination of the hydraulic interaction between the rivers and groundwater, as the most significant water resources in arid and semi-arid regions, attracted a great attention recently. In recent years, several methods have been used for the study of these water exchanges such as seepage meters, minipiezometers, temperature data loggers and the study of the physicochemical parameters. The Dez River that is the third largest river in Iran also is one of the important surface water resources in the northern part of Khuzestan province. In this research, the water physicochemical parameters were used to assessment of the interaction between the Dez River and aquifer in the north part of Dezful-Andimeshk district. To this purpose, the temporal and spatial variations of river and groundwater quality parameters have been studied. The physicochemical analysis results of the river and quality monitoring wells have been used for the temporal assessments of river-aquifer interaction. For spatial assessment of the river-aquifer interaction, 69 groundwater samples were collected from the abstraction wells. Hydrochemical diagrams such Piper and composition diagrams along with some statistical methods such as Cluster Analysis were applied to the interpretation of the results of the water samples analysis. Also, the PRO-GRADE computer code was used for evaluation of the achieved results. The results of this study show that the Dez River has a losing nature and its recharge water in to the underlying groundwater body can enhance the quality of the groundwater in the study area. The measured nitrate concentration of river and groundwater also shows the positive role of river infiltrated water on the groundwater quality