Coastal Management:[edit | edit source]
Coastal management is managing the coastline in order to protect coastal settlements. We use forms of Coastal defences in order to protect coastal towns and villages. We also use these to protect our beaches, as soon we will not have any beaches if we do not guard them.
This is a solid structure made of concrete blacks which reflect the waves. They are able to withstand severe storms, however their cost and maintenance is very high. There is likely to be undercutting of wall.
This is very similar to the vertical seawall, however, it is built with a curved face which absorbs more energy. This therefore means that there is less chance of the the waves overtopping and there is even spreading of the waves' energy. However, the disadvantages are similar to the vertical seawall: it is very high cost, although the maintenance is slightly less due to the reduced chance of scouring due to the curved face.
Groynes are posts placed at intervals on a beach. They prevent longshore drift in In 1991 almost £2 million was spent on two rock groynes.
Revetments are sloping concrete walls that are laid like a carpet along coastline; reduces the wave energy and stops Longshore Drift. Costs about £2000 per metre.
Gabions are strong wire baskets filled with stones. As the waves travel through them their energy is dissipated (reduced). They gradually get covered in grass and sand over time, so they do not look abnormal or out of place. Cost about £1000 per metre.
Rip Rap :
Man-made boulders which interlock to protect the coast by absorbing and dissipating (decreasing) the wave energy. £3500 per metre.