1) Hard Defences
Static shoreline structures such as those constructed from timber, steel, concrete, asphalt and rubble.These involve linear structures such as sea walls, revetments and breastwork and control structures of artificial headlands, offshore breastwork and groynes.
(2) Soft Defences
Mobile/ responsive defence measures which seek to work with nature rather than control it. Such structures may consist of sand or shingle beaches and dunes or banks) which may be natural or constructed, and may include control structures. These can include soft solutions of beach nourishment, cliff/dune stabilisation, bypassing and managed retreat.
Static shoreline structures such as those constructed from timber, steel, concrete, asphalt and rubble.These involve linear structures such as sea walls, revetments and breastwork and control structures of artificial headlands, offshore breastwork and groynes.
(2) Soft Defences
Mobile/ responsive defence measures which seek to work with nature rather than control it. Such structures may consist of sand or shingle beaches and dunes or banks) which may be natural or constructed, and may include control structures. These can include soft solutions of beach nourishment, cliff/dune stabilisation, bypassing and managed retreat.
DEFENCE COST ADVANTAGES AND DISADVANTAGES
Sea wall £6000 per m Very strong, but may reflect waves. Very expensive.
Rock £4500 per m Absorbs the energy of the waves, rock breaks up over time.
Revetment
Offshore £5000 per m Protects the base of the cliff. Must be large rocks.
Groynes £5000 each Will trap sand.
Beach £3500 per m Absorbs wave action. May need replacing
Nourishment
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