The Netherlands has 3,000 km of primary flood defences and 14,000 km of regional flood defences. There is growing awareness that safety standards in the Netherlands should be revised and that space limitations require that flood defences be combined with other functions. These two elements are referred to as the new approach to flood defence systems.
There are several types of multifunctional flood defences that are appealing. The first types are multipurpose defences that border the sea. The defence must resist storms along the Dutch coast and be able to tolerate high water levels and heavy wave attack. The coastline also performs many other functions in urban areas such as housing, recreation and transportation.
Other types are defences along the rivers in Holland which should be able to resist prolonged flood. The flood defence consists of several parts and is usually embedded in the old town that often borders on the water. The versatile use of the territory and the monumental buildings inside and outside the dikes is very complex. Similar problems are encountered in other countries.