Planning of Coast Protection

Abstract

A natural beach of sand or shingle is an economic means of absorbing the energy of breaking waves, and thus protecting an erodible coastline. Chapter 4 indicates how a coastal regime may vary with changes in off-shore topography. It is also necessary to consider how the regime may be affected by maritime works interfering with the natural processes of littoral drift. After allowing for such factors, the engineer has to consider the sufficiency of the natural beach material for continuous protection, making provision for possible short-term and long-term variations. At this stage, he may be able to assess whether or not artificial means are necessary to augment or sustain the beach; he may alternatively decide that some other expedient will be necessary to replace the function of the beach in full or in part. These stages in the evolution of an economic scheme of coast protection are described in outline below.