The sand on the Dutch coast provides natural protection against the sea. Because of the action of wind, waves and currents, sand is constantly lost to the sea. To maintain the protection afforded by the beaches and dunes, Rijkswaterstaat maintains the coast (Dutch) with nourishment operations involving millions of cubic metres of sand taken from the bed of the North Sea. The Sand Decision defines the goals and implementation of these operations.
The principle underlying the Sand Decision is ‘soft where possible, hard where needed’. In other words, the character of the coastline should remain as natural as possible, with dunes and beaches being the basis for coastal protection. To maintain the sand balance, larger sand nourishment operations will be needed in the future as sea levels continue to rise due to climate change. These operations contribute not only to preserving the coastline but also to local and regional goals for an economically strong and appealing coast.
Knowledge
More knowledge is needed to make sand nourishment more effective and cost-efficient. So learning in practice is an important component of the Sand Decision. That means conducting pilot projects, monitoring and research, and using the results to inform new decisions. That was done until the end of 2020 in the research programme Coastal Genesis 2.0 (Dutch).
All data collected in the research programme have been available for everyone to download since the end of 2019. This means that scientists in the Netherlands and abroad have a wealth of information at their disposal.
The follow-up to Coastal Genesis 2.0 (additional monitoring, research and pilot projects) is part of the Sea Level Rise Knowledge Programme. The aim is to better anticipate future developments that will affect the sand system. At present, sand nourishment involves 12 million cubic metres of sand annually; for the time being, that is enough.