Method for quantitatively assessing the impact of an inter-basin water transfer project on ecological environment-power generation in a water supply region

Abstract

To tackle ever-changing global water problems, inter-basin water transfer (IBWT) projects provide water supply alternatives for water-scarce regions and create potential risks for water-supply regions. To analyze the multiple interrelated impacts of IBWT projects on supply regions, in this study, we establish a cascade multi-objective complementary optimal scheduling model and apply the model to the water supply regions of the west route of China’s South-North Water Transfer Project and the Dadu-Minjiang Water Transfer Project. With the goal of fully utilizing water resources to gain comprehensive benefits, we objectively and quantitatively evaluate the impacts of IBWT projects on the ecology and hydropower generation of water supply regions. To reduce the complexity of solving the model, the model is decomposed into a two-stage optimization model and is solved with particle swarm optimization and fuzzy optimization. The results show that: (1) The multi-objective model that simultaneously considers minimal ecological water shortage degree, maximal power generation, and the maximization of the annual minimum output is more conducive to the full utilization of water resources. (2) The factors affecting the ecological flow, the power generation and its structure in the water supply region, and the annual minimum output are different. (3) To deal with risks, the upstream power station in the water supply region is controlled to meet the ecological needs as the primary goal, and the downstream power station is mainly responsible for the task of compensating and adjusting the output gap during the dry season. This study can provide technical support for the demonstration and decision-making of IBWT projects, and it explores the ideas of water resource planning and management.