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The process of beach nourishment is literally feeding the beach with more sand to replace that which is eroded away from it. New sand or shingle is dumped on the beach and spread out to replace the sediment that has been removed. The new material may be brought in by road, rail or sea, or even pumped up from the sea bed off shore. In some places, such as the Netherlands, nourishment material is dumped off shore so it can be brought onshore by the natural movement of the waves. By placing it off shore it helps to reduce wave energy hitting the beach and becomes better compacted when it is deposited on the beach.
Beach nourishment does not stop erosion; it slows down the effect by replacing some or all of the material removed by the sea.
Nourishment can be applied to sand, shingle and even cobble beaches, but the new sand dumped directly onto the beach does erode more quickly than the original material. This is because it is not as well compacted as naturally deposited material.
The advantages of nourishment are that it maintains or increases the size of the beach, so it protects the coast against longshore drift and storm waves. It looks natural because only natural materials are added to the beach. By adding more material than is eroded, the beach can be increased in size and the coastline moved seawards, giving even more protection to the land.
Beach nourishment, with materials identical to the original sand or shingle, is popular with tourists and beach users as it produces a natural looking beach without the less attractive groynes, sea walls and riprap associated with hard engineering. Compared to building hard structures it is also a cheap solution.
Disadvantages include not being a permanent solution – you will always have to add more sediment to replace what is lost. The actual dumping of new material can damage the ecosystem of the beach, destroying both animals and plants.