关键词: 水位上浮；消落期；防洪库容；水库调度；库容整体运用；防洪风险；金沙江下游梯级水库

Abstract: The floating-up of the operating water level at the end of the drawdown period is an effective way for reservoirs to increase power generation, reduce water discharge, and improve comprehensive benefits. However, the floating-up of the operating water level should be scientifically coordinated with the relationship between flood control and water resources utilization. Taking the cascade reservoirs in the lower reaches of the Jinsha River (Wudongde, Baihetan, Xiluodu, and Xiangjiaba cascade reservoirs) as the research object, based on a comprehensive analysis of the flood characteristics of different river sections at the end of the drawdown period, the requirements for reserving flood control storage capacity for different river sections by the cascade reservoirs in the lower reaches of the Jinsha River and the research ideas for floating up the operating water level at the end of the drawdown period are clarified. Based on the analysis of typical flood characteristics and the overall operation strategy of the cascade reservoirs, the conditions and operation methods for floating up the operating water level at the end of the drawdown period are proposed, and the potential flood control risks and countermeasures are discussed. The research results show that at the end of the drawdown period, when the cascade reservoirs in the lower reaches of the Jinsha River do not need flood control operation, and the water level at the Lianhuatang Station in Chenglingji and the combined flow of the four rivers in Dongting Lake meet certain conditions, the cascade reservoirs as a whole can be operated with a floating-up capacity of no more than 1.055 billion m³ above the flood limit water level. It is recommended that the floating-up storage capacity be preferentially allocated to the Xiluodu Reservoir. On the premise of ensuring flood control safety, the comprehensive benefits of the cascade reservoirs can be effectively improved.

Key words: Water level floating-up; Drawdown period; Flood control storage capacity; Reservoir operation; Overall utilization of storage capacity; Flood control risk; Cascade reservoirs in the lower reaches of the Jinsha River