Study on the emergency rescue and response at the Dishuiyan Reservoir Dam induced by Hunan "6.16" rainstorm in 2024

Under the sustained influence of the "6.16" rainstorm process in Hunan Province in 2024, the Dishuiyan Reservoir has experienced water levels exceeding its normal storage capacity. In addition, a large area of scattered seepage occurred in the middle of the downstream secondary slope, accompanied by 8 concentrated leakage points and tension cracks,despite the emergency implementation of multiple "seepage diversion + drainage" measures on site, the situation continued to deteriorate. To successfully develop an optimized and effective emergency response plan, it was necessary to rapidly bring the dam emergency under control and resolve it.Based on the current dam risk status and measured geotechnical parameters of the dam body, this study employs the finite element method to simulate and calculate the dam stability before and after the implementation of the preliminary emergency response plan. It analyzes the underlying causes of the ongoing deterioration of the dam risk and proposes an optimized solution involving "adding a seepage-diverting toe weight at the downstream slope toe, increasing the density and depth of seepage diversion trenches, and densifying drainage holes within seepage diversion wells." Following the implementation of the optimized plan, the dam risk was successfully brought under control and gradually eliminated.The results indicate that: The calculated stability values of the dam under three conditions—at the time the risk was identified, after the initial emergency measures were implemented, and after the optimized solution was applied—generally align well with the actual field observations. The preliminary comprehensive emergency rescue plan was generally reasonable, as it provided some relief to the dam's emergency situation, although the situation was still evolving slowly. After the implementation of the optimized solution, the risks of seepage and anti-sliding instability of the dam were completely eliminated, effectively bringing the emergency situation under control. It can be seen that the finite element calculation results of dam stability, which take into account the actual on-site conditions, exhibit high accuracy. These results can guide the scientific improvement of emergency rescue plans and provide valuable reference for optimizing emergency response measures for dams at risk during the flood season.