Hydropower plays a significant role in global energy production, contributing 16%of the world’s electricity and 70% of renewable energy. In Sweden, hydropowerconstitutes 45% of the nation’s electricity generation and offers substantial reservoirenergy storage capacity.This study focuses on hydraulic jump-type stilling basins, crucial for energy dissipationin hydropower projects. Collaborating with Vattenfall R&D in Älvkarleby,it investigates the failure conditions of a stilling basin at the spillway bottom. UsingANSYS Fluent, three specific scenarios involving bottom cavities in the stillingbasin are explored: a crack at the joint, a vertical offset crack at the joint, and avertical offset crack at the joint with baseflow leakage.The findings reveal insights into the performance of stilling basins under differentscenarios, exploring their hydraulic characteristics, including flow patterns,velocity distribution characteristics, static pressure distribution, pressure differentials,pressure fluctuations, and energy dissipation efficiency. These results willcontribute to understanding the mechanisms of stilling basin damage and aim toprovide valuable information for future design improvements and safety measuresin hydropower systems.