coastal protection

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Measures taken to prevent coastal erosion. Many stretches of coastline are so severely affected by erosion that beaches are swept away, threatening the livelihood of seaside resorts, and buildings become unsafe.

To reduce erosion, several different forms of coastal protection are used. Structures such as sea walls attempt to prevent waves reaching the cliffs by deflecting them back to sea. Such structures are expensive and of limited success. Adding sediment (beach nourishment) to make a beach wider causes waves to break early so that they have less power when they reach the cliffs. Wooden or concrete barriers called groynes may also be constructed at right angles to the beach in order to block the movement of sand along the beach (longshore drift). However, this has the effect of ‘starving’ beaches downshore: ‘protection’ of one area usually means destruction of another.

Rock armour refers to large blocks of stone dumped on a beach or at the base of a cliff to reduce erosion. Hard engineering refers to constructed/built devices, while soft engineering refers to natural features such as salt marshes or sand dunes, which may help to protect against erosion.

Coastal protection may also refer to the process of simply leaving the coast to the elements but removing the harmful factor of human population and development.

White represents the snow on Monte Titano and the clouds above. Blue stands for the sky. Effective date: 6 April 1862. >>