Strategy |
Description |
Advantages |
Disadvantages |
Sea Wall |
A wall, usually concrete, and curved outwards to deflect the power of the waves
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Most effective at preventing both erosion and flooding (if the wall is high enough)
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Very expensive to build and maintain
It can be damaged if the material is not maintained in front of the wall
Restricts access to the beach
Unsightly to look at
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Groynes |
Wood, rock or steel piling built at right angles to the shore, which traps beach material being moved by longshore drift
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Slows down beach erosion
Creates wider beaches
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Stops material moving down the coast where the material may have been building up and protecting the base of a cliff elsewhere
Starves other beaches of sand. Wood groynes need maintenance to prevent wood rot
Makes walking along the shoreline difficult
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Rip-rap |
Large boulders are piled up to protect a stretch of coast
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Cheaper method of construction
Works to absorb wave energy from the base of cliffs and sea walls
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Boulders can be eroded or dislodged during heavy storms
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Gabions |
Wire cages filled with stone, concrete, sand etc
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Cheapest form of coastal defence
Cages absorb wave energy
Can be stacked at the base of a sea wall or cliffs
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Wire cages can break and they need to be securely tied down
Not as efficient as other coastal defences
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Revetments |
Sloping wooden or concrete fence with an open plank structure
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Work to break the force of the waves
Traps beach material behind them
Set at the base of cliffs or in front of the sea wall
Cheaper than sea walls but not as effective
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Not effective in stormy conditions
Can make beach inaccessible for people
Regular maintenance is necessary
Visually unattractive
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Off-shore barriers |
Large concrete blocks, rocks and boulders are sunk offshore to alter wave direction and dissipate wave energy
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Effective at breaking wave energy before reaching the shore
Beach material is built up
Low maintenance
Maintains natural beach appearance
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Expensive to build
Can be removed in heavy storms
Can be unattractive
Prevents surfing and sailing
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