hard engineering

• Define 'hard engineering'.

  Hard engineering involves the uses of man-made structures to reduce the erosive potential of waves.
• Describe what sea walls are and how they work.

  Walls are built at the back of beaches to reflect waves back to the sea. They are usually curved to better reflect waves.
• What are the advantages of sea walls?

  They prevent erosion but not the movement of sediment, which can affect other areas. Well-maintained walls can last for years.
• What are the disadvantages of sea walls?

  They create a strong backwash, which can erode wall foundations. They are expensive to build and maintain, and can appear unsightly.
• Describe what rock armour is and how it works.

  Large boulders are placed along the coastline to absorb the power of waves.
• What are the advantages of rock armour?

  It is highly effective at absorbing wave power. It is relatively cheap, quick to build and easy to maintain.
• What are the disadvantages of rock armour?

  Boulders are often sourced from other location and may appear unsightly next to the local geology.
• Describe what groynes are and how they work.

  Concrete or wooden barriers are built at right angles to the beach to prevent longshore drift, trap sediment and absorb the power of waves.
• What are the advantages of groynes?

  They are relatively cheap and effective at preventing erosion. They create larger beaches, which can attract more tourists.
• What are the disadvantages of groynes?

  The restriction of the movement of sediment may simply move the problems of erosion further down the coast.
• Describe what gabions are and how they work.

  Wire wages filled with rocks are placed at the base of cliffs to absorb wave energy.
• What are the advantages of gabions?

  They are cheap and easy to construct, making them a good short-term solution. They are often made from local materials.
• What are the disadvantages of gabions?

  The wire cages are ugly and can erode within 10 years. If broken, loose material can be dangerous.