Structural integrity for energy dissipation of spillways is essential to maintain a high dam safety level. In some Swedish low-head facilities (< 15 m), damages appear also where flow velocities are expected to be too low to cause cavitation. To better understand the reason for damages a study including desktop survey, hydraulic scale model tests and numerical modelling with CFD has been initiated at Vattenfall R&D. Most common damages found in an inventory were erosion of bedrock in stilling basins, often in or adjacent to weak zones (clay filled cracks or crushed rock). Sometimes the damages progressed under concrete structures. A flow velocity above 15 m/s atthe end of the crest or at the intersection with the downstream water level seems to be a limit for when damages occur in the studied spillways. Scale model tests (1:17.5) of a case with damages has been performed to study the energy dissipation and potential causes for initiation of the damages. A CFD-model (OpenFOAM) of the same case, in model scale, has been set up to make a comparison. Measurements of flow velocities give that the tested scenario could cause flow velocities above 15 m/s in prototype scale. The pressures given by the CFD-model where in line with the ones from the model tests. From the model test the pressures, near the transition from the crest to the stilling basin, were low but not sub atmospheric. In the CFD-model the indicated risk for cavitation was high and in the same area as the real damages. Excluded from both model tests and CFD-model is the fact that cracks where visible in the real structure. Therefore, it cannot be ruled out that the initiation of damages also was stagnation pressure in the cracks. The study will continue with further tests with more pressure gauges and simulations. and the validation of the numerical model and conclusions presented are therefore preliminary.