Evaluation of Flood Routing Method's Efficiency Case Study: Dez River

Routing methods has an important role in flood forecasting, reservoir design, river training, etc. Flood-routing techniques are utilized to estimate the stages, or rates of flow, in order to predict flood wave propagation along river reaches. There is a multitude of flow routing models which can be broadly classified into hydrologic and hydraulic models. The hydraulic techniques are complex and often difficult to implement and in practical applications, the hydrological routing methods are relatively simple to implement and reasonably accurate. In this research some hydrologic approaches including Muskingum, Convex and modified Att-Kin methods were applied to flood routing. 26 flood events have been used to evaluation of the methods in the Harmaleh- Bamdezh reach that was situated in the Dez River. Some goodness of fit criteria such as RMSE, Coefficient of Correlation and Coefficient of efficiency used to estimation of methods accuracy. Visual comparisons show that RMSE is the best goodness of fit criterion. The results show that the graphical approach is most appropriate method for determining Convex and Muskingum parameters. It can be stated that Convex, Muskingum, Modified Att-Kin and Muskingum-Conge methods have the most accurate results, respectively. However, the average discharge or half of peak discharge shows better results, but in general, selection of different types of flow having no significant effect on model efficiency.