Underwater inspection of a certain hydropower station revealed that the concrete of the second phase of the spillway gate slot

the concrete of the stilling pool

the foundation of the retaining tank and the downstream guide wall had suffered erosion damage. The reasons for the erosion of flood discharge and energy dissipation structures were analyzed from the perspectives of inflow conditions over the years

the hydraulic design of flood discharge and energy dissipation facilities

the construction quality of the stilling pool

and the opening and closing procedures of the gates. On this basis

engineering measures such as optimizing the shape of the energy dissipation pool and promptly repairing the damaged parts were proposed. In addition

management measures such as conducting flow state observation and recording during flood discharge

refining the gate opening and closing procedures

regularly carrying out underwater inspections

and promptly eliminating defects were proposed.