[EN] The still water level (SWL) during a storm is always dynamic (storm surge). The variability of the water level can be schematized as a time-varying hydrograph of a certain duration. Typically, the individual overtopping volume distribution and probability of individual volume overtopping is a function of the ratio between the freeboard Rc (the structure crest elevation above SWL) and the significant wave height Hm0. Since the variation during a storm of the SWL changes the freeboard, the individual overtopping volume is variable. Typically, in the laboratory the wave overtopping on coastal defence structures is investigated for a constant water level (CWL) and a pre‐determined structural exposure time frame, not considering any variable water level (VWL). For example, the individual volumes in the rise of the storm surge will pre-load (saturate) the dike and potentially weaken it before the largest overtopping volumes occur during the peak of the storm. No research exists yet on the study of individual overtopping volumes for a VWL situation, so its realization is required. Then, a comparison of the available literature for the CWL situation is carried out to analyze the validity of the prediction formulas for this case, within the UG17 dataset measured in the wave flume facility located at the Coastal Engineering Laboratory of the Ghent University. Following a sensitivity analysis, the best results are found for a certain percentage of the highest overtopping volumes, while the equivalent non-dimensional freeboard predicts equally well both CWL and VWL situations. Hence, a practical application of these considerations is applied to a real storm of a return period between 40 and 45 years to redesign the Research Dike Raversijde, located in the Belgian coast, in order to limit the overtopping of the structure to 1 l/s/m, following Belgian standards. ; [ES] El nivel del agua durante una tormenta es siempre dinámico. La variabilidad del nivel del mar puede esquematizarse como un hidrograma variable en el ...