In order to be able to fulfill the requirements concerning renewable energy, a large amount of energy should be gained from offshore windfarms. Mainly because of energetic reasons, these parks must be placed further and further offshore. Building these parks, a lot of problems occur. This project proposal comprehends on the one hand a desk study to investigate these problems and on the other hand an experimental study towards one specific problem: scouring of the bottom material around the foundation of the windmills.