Document Type : Research Paper
Abstract
An important problem in performance evaluations of irrigation systems is the difficulty of the determining share of structural and operational elements and determining improvement solutions. In most studies, the combined impact of structural and operational elements on the performance of irrigation systems is assessed. Some researchers try to separate the effects of structural and operational elements, but ambiguity in the proposed indicators affects the accuracy of the separation. In this research, separate indicators for the performance evaluation of irrigation systems are defined. By considering the objectives of water distribution and the interaction of operational and structural elements on the performance of the system, indicators for depth of water and delivered flow are defined. Two other sets of indicators are defined to accommodate the importance of operation timing and flexibility of irrigation systems in meeting water user requirements. To test the applicability of the indicators, an operational scenario was assessed for the E1R1 canal of the Dez irrigation network. To evaluate this scenario and its appropriate improvement options, the canal was simulated using an ICSS hydrodynamic model. The results for this scenario show that the total, structural and operation depth deficit indicators are 78%, 90%, and 86%, respectively. The total, structural, and operational adequacy indicators are 96%, 94%, and 90%, respectively. The improvement option improved the operational, structural and overall depth deficit indices by 12%, 7% and 18%, respectively. In addition, operational, structural and overall adequacy indices for the improvement option improved by 9%, 4% and 13%, respectively. The results show the capability of the proposed indicators in determining the share of structural and operational elements on the performance of an irrigation system which can be easily used to prioritize improvement options.
Keywords
)