A New Evaluation for Water Transfer Optimal Schemes with the Consideration of Reliability, Stability, and Severity

To alleviate the water resources shortage in arid or semi-arid area, various water transfer projects have been constructed and put into operation over the last few decades. Apart from the available water, the allocation scheme also determines whether the water demands alongside can be satisfied well. Different from traditional evaluation without considering how often the failure occurs and how severe magnitude the failure may be when operating a scheme, this study proposes three indexes to evaluate scheme performance comprehensively, which are: (1) the satisfaction degree of a selected scheme (reliability); (2) the ability of the system to recover from a failure to satisfactory state (stability); and (3) the maximum damage of operating a scheme (severity). To illustrate the application of these evaluation indexes, an optimization model and an exponent describing differences among schemes are established, and then applied to the east route South-to-North Water Transfer project in China. The result shows that there exist tradeoffs among scheme’s benefits, which is described by reliability, stability, and severity. And with the increase of the exponent, the optimal scheme would consider deficit distribution more. In order to make the water transfer system with high reliability, high stability, and low severity, the exponent should be in the range of 1.0–2.0. These findings can be taken as the references to the operation of the water transfer projects.