Management of Beach Nourishment in an Open Sand System

The nourishment of beaches is an environmentally friendly method of shore protection but the annual sand requirement may lead to substantial expenditure. Therefore the annual sand demand should be minimized. Factors which affect the sand demand along a sandy coastline in order retain the shoreline at a given position will be discussed. A wide normally dry beach on which waves can dissipate their energy at raised water levels without substantial reshaping of the underwater profile is desirable. Where such a beach cannot be created measures have to be taken to minimize sand losses from dunes during extreme events into the everyday surf zone. Furthermore the sand requirement for an open sand system, like the Island Sylt/North Sea, can be obtained by a reduction of the amount of sand from longshore transport which is carried over the ends of the island and is lost from the system.