Abstract: This study focuses on the Tianhuangping and Changlongshan pumped storage power stations—cascade facilities in the Huxi River basin—to establish one- and two-dimensional dam-breach flood evolution models, formulate dam-breach calculation schemes, and simulate the evolution of dambreach floods under various operating conditions. Based on these analyses, the safety risks of cascade pumped storage power stations are studied and recommendations for operational management are advanced. The results indicate that, under conditions of high flood volume, pre-release from Longlongshan lower reservoir has a negligible impact on flood regulation. When the Tianhuangping and Changlongshan upper reservoirs experience overtopping, their storage capacities are roughly equal, and the downstream flood propagation patterns following separate failures are largely identical. Under condition 1—where the lower dam of Tianhuangping pumped storage power station overflows and breaches—both the discharge flow rate and flood volume are greater, causing the maximum flood water level in the lower reservoir of Changlongshan pumped storage power station to approach the dam crest elevation, posing a risk of consecutive breaches. Except for condition 1, the maximum flood levels in both lower reservoirs in other conditions maintain a safety margin relative to the dam crest elevation, indicating that the cascade pumped storage power stations are generally safe. The results of these dam breach flood calculations and the management recommendations can provide data support for the development of emergency response plans, while also serving as a basis for emergency decision-making and rescue operations.

Key words: safety risk analysis, dam failure analysis, emergency management, cascade reservoirs, Tianhuangping pumped storage power station, Changlongshan pumped storage power station

摘要： 笔者以浒溪流域梯级抽水蓄能电站天荒坪、长龙山为研究对象，建立一、二维溃坝洪水演进模型，拟定溃坝计算方案，计算不同工况时的溃坝洪水演进过程，进而探讨梯级抽水蓄能电站安全风险，提出运行管理建议。结果表明，对于洪水洪量较大的情况，长龙山下水库预泄对于调洪的影响不明显；天荒坪、长龙山上水库漫顶时库容接近，分别溃决后，向下游演进过程规律也基本相同；工况1天荒坪下库坝漫顶溃决，下泄流量和洪量均更大，导致长龙山下水库最高洪水位接近下库坝坝顶高程，面临连溃风险。除工况1存在两座下库坝连溃风险之外，其余工况两座下水库最高洪水位距离坝顶高程仍有一定裕度，梯级抽水蓄能电站总体安全。本次溃坝洪水计算成果和管理建议可为应急预案编制提供技术支撑，同时可为应急决策、救援提供依据。

关键词: 安全风险分析, 溃坝分析, 应急管理, 梯级水库, 天荒坪抽水蓄能电站, 长龙山抽水蓄能电站