From the integrated coastal security and from OWplan that the ports weak links in the sea defenses. Here are needed measures (storm walls). For the dimensioning of this storm wall there is still a lack of knowledge, which makes physical tests are necessary. The assignment has for its object the determination of the overtopping discharge on and the forces on a storm wall. The tests cover the overtopping problems at the docks in ports (Ostend and Zeebrugge) which is determined from an assessment that there is currently an unsafe situation when extreme storms (very high risk of flooding).