Developing Reach Sensitivity Indices and a New Algorithm for Studying Flow Characteristics in Irrigation Channels

Sensitivity analysis approach should be regarded as a new means which was introduced recently for flow assessment of irrigation systems. In this paper, three hydraulic sensitivity indices for channel reach were developed, and the algorithm for analyzing flow based on these indices was presented. For evaluating the efficiency of indices and the proposed algorithm, a real case was simulated by SOBEK model. Using the results of two alternative operational scenarios, i.e. the minimum and maximum operated discharge values of the canal, the quantified values of indices were calculated. The results show a successful application of the reach sensitivity indices in analyzing and predicting flow conditions in the system. A proper evaluation of the system response to hydraulic perturbations, which was achieved by using the proposed convenient means, could improve the network operation, and increase the overall water use efficiency. The proposed indices and algorithm could be applied in design process and also in operational period of irrigation systems.