Modeling of Water Quality Parameters of Karaj River Using CE-QUAL-W2 Model

Nowadays, due to the expansion of societies and consequently increased use of water resources, abnormalities in rivers have increased and eventually led to changes in water quality conditions. Therefore, it is essential try to develop a management system to predict the pollutants behavior and also prevent excessive environmental pollution. The aim of this research is to model the changes of water quality parameters of Karaj River using CE-QUAL-W2 model. In order to achieve the research goal, hydrodynamics of the system (water velocity) and river quality parameters including nitrate, phosphate, algae, ammonium, dissolved oxygen, biological oxygen demand were calibrated and then verified. The results show a suitable matching with observed data. Moreover comparing the results of simulated concentration of DO and BOD with the standard level of these parameters for surface water is an evident for the health of the river. Considering the accurate predictions of the model, it can be concluded that utilizing of appropriate mathematical models with spending less time and cost compared to field monitoring and laboratory observations for qualitative simulation and representing management scenarios would be a very useful tool in water resource management and would help the planners and managers as a decision support tool to achieve the goals of sustainable development.