- مبلغ: ۸۶,۰۰۰ تومان
- مبلغ: ۹۱,۰۰۰ تومان
Article history: Received 15 September 2017 Received in revised form 10 December 2017 Accepted 30 January 2018 Available online xxxx Editor: R. Ludwig Irrigation canal networks, as the primary agricultural water conveyance and delivery systems, are exposed to a variety of hazards affecting the water distribution processes. This study, for the first time, develops a comprehensive risk management framework for the canal network through a Fuzzy Hierarchical method. In this regard, the risk is analyzed by a combination of probability, consequence, and vulnerability against identified hazards based on the hierarchical framework. The developed model is based on fuzzy numbers to consider the uncertainties arise from experts' opinion. To aggregate the calculated risk in the hierarchical framework, the Fuzzy Simple Additive Weighting (FSAW) approach was employed. To enhance the reliability of the water distribution system and decrease the risk of failure, six risk management alternatives are proposed based on the risk assessment results and the most significant hazards. To prioritize managerial scenarios, two sets of criteria were selected including quantitative criteria (consisting of cost of operation and risk reduction) and a qualitative set (compromising social and operational criteria). The risk management scenarios were prioritized based on two rational multi-criteria decision-making (MCDM) methods of a Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Simple Additive Weighting (SAW). Regarding different degrees of importance of the criteria, a pair-wise comparison was conducted by a group of experts to determine the relative weight of the criteria. According to the risk assessment results, the riskiest hazards are poor maintenance, seepage, unexpected event, drought, and vandalism of the structure. Moreover, employing the MCDM model in risk-based decision-making reveals that “maintenance improvement” is ranked as the first scenario, with score values of 0.851 and 0.237 employing the SAW, and TOPSIS approaches, respectively.
This study aims to present an expert-oriented risk assessment model to evaluate the risk in an irrigation canal and its corresponding components. The developed model identified dangerous hazards which can lead to failure of the primary water conveyance and delivery systems. A wide range of structures and related hazards are taken into account in the model to present a general framework for employing in any irrigation district, including ones with different types of conveyance; water level regulating, and off-take structures. The risk of failure is considered as the combination of the probability of hazards; the consequence of failure; and the vulnerability of the system against the hazards. The risk was calculated according to a hierarchy relation of the subcomponents and structures. Using the uncertainties revealed by the comments and opinions of managers and experts, the risk assessment model was developed based on a fuzzy triangular membership function. Although the extensive application of such risk assessment models has been reported for the urban water systems and sewer collection systems previously, this study for the first time employed the model for risk assessment of irrigation districts.
Based on the findings of the risk assessment model in this study, “poor maintenance,” “seepage,” “unexpected event,” “drought,” and “vandalism” were found to be the riskiest hazards relating to the system's components and structures. Among the elements of the conveyance and distribution system, the regulatory structure was found to be the riskiest element.