Rock scours after a spillway of a dam can lead to major problems regarding the stability of the structure. The pressures on the floor are dependent on the height of the dam and the water cushion in the pool. They can reduce the effective stress between the rock blocks significantly and hence the friction resistance. This mechanism leads to proper instabilities in the foundation and the structure. A model test at the Institute of Hydraulic Engineering and Water Resources Management should expose the pressures on the bottom floor. The results of the test case show a significant decrease of these pressures due to the evaluated configuration of the model. Further investigations, in a more detailed model, with cracks in the rock for different quantities of the jet velocity and the depth in the stilling basin are planned as well as numerical simulations by means of fluid-foundation interaction for comparison reasons.