A short survey of the nine floods which have ravaged the Netherlands since 1877 is here presented. The flooded areas are given on the maps; the figures in the tables give the inundated surface in ha per province. From these data it can be seen of what great importance the closing of the Zuiderzee and of the inlets between the Westerschelde and the Rotterdamse Waterweg (the so-called Delta plan) is to the safety of the Netherlands.