10.11+10.12 Coastal management: hard engineering

Question 1

What is hard engineering

Answer 1

Involved building artificial structures to try to control natural processes

Question 2

What are sea walls

Answer 2

Concrete walls that are placed at the foot of a cliff to prevent erosion. They are curved to reflect the energy back into the sea.

Question 3

What are sea walls

Answer 3

Concrete walls that are placed at the foot of a cliff to prevent erosion. They are curved to reflect the energy back into the sea.

Question 4

Sea walls advantages

Answer 4

• Effective at protecting the base of the cliff.
• Sea walls usually have promenades so people can walk along them.

Question 5

Sea wall disadvantages

Answer 5

• Waves are still powerful and can break down and erode the sea wall.
• Expensive - approximately £2,000 per metre.

Question 6

What is rock armour

Answer 6

Large boulders placed at the foot of a cliff. They break the waves and absorb their energy.

Question 7

Rock armour advantages

Answer 7

• Cheaper than a sea wall and easy to maintain.
• Can be used for fishing.

Question 8

Rock armour disadvantages

Answer 8

• They look different to the local geology, as the rock has been imported from other areas.
• The rocks are expensive to transport.

Question 9

What are gabions

Answer 9

Rocks are held in mesh cages and placed in areas affected by erosion

Question 10

Gabions advantages

Answer 10

• Cheap - approximately £100 per metre.
• Absorbs wave energy.

Question 11

Gabions disadvantages

Answer 11

• Not very strong.
• Looks unnatural.

Question 12

What are groynes

Answer 12

Groynes are wooden or rock structures built out at right angles into the sea.

Question 13

Groynes advantages

Answer 13

• Builds a beach - which encourages tourism.
• They trap sediment being carried by longshore drift.

Question 14

Groynes disadvantages

Answer 14

• By trapping sediment it starves beaches further down the coastline, increasing rates of erosion elsewhere.
• They look unattractive.