Coastal Management

Question 1

what is hard engineering in terms of coasts?

Answer 1

manmade structures built to control the flow of the sea and reduce flooding and erosion

Question 2

what is soft engineering in terms of coast?

Answer 2

schemes set up using knowledge of the sea and its processes to reduce the effects of flooding and erosion

Question 3

what are the forms of coastal hard engineering?

Answer 3

-sea wall
-gabions
-rock armour
-groynes

Question 4

what is a sea wall?

Answer 4

a wall made out of hard material like concrete that reflects waves back to sea

Question 5

what are the advantages of using a sea wall?

Answer 5

-it prevents erosion of the coast
-it acts as a barrier to prevent flooding protecting houses by the coast

Question 6

what are the disadvantages/costs of using a sea wall?

Answer 6

-sea walls are very expensive to to build and maintain as they create strong backwashes which can erode under the wall weakening it. This could lead to the diversion of finance from other things to help maintain it
-some people think they are unsightly which can reduce tourism

Question 7

what are gabions?

Answer 7

a wall of wire cages filled with rocks usually built at the foot of cliffs

Question 8

what are the advantages of gabions?

Answer 8

-the boulders absorb wave energy reducing the erosive force of waves meaning there is less erosion and sediment displacement reducing coastal erosion and the destruction of coastal habitats
-it is a fairly cheap defence

Question 9

what are the disadvantages/costs of gabions?

Answer 9

-they are not pleasent to look at
-the wire cages can corrode over time reducing its effectiveness and stability which can pose a risk to communties and infrastrcuture

Question 10

what is rock armour?

Answer 10

boulders that are piled up along the coast (its also sometimes called a rip-rap)

Question 11

What are the advantages of rock armour?

Answer 11

-reduces wave energy
-fairly cheap defence

Question 12

what are the disadvantages of rock armour?

Answer 12

-they can be moved around by strong waves so they need to be replaced

Question 13

what are groynes?

Answer 13

-wooden or stone fences that are built at right angles to the coast
-they trap material transported by long shore drift

Question 14

what are the advantages of groynes?

Answer 14

• they create wider beaches which slow the waves , this gives protection from flooding and erosion and also attracts toursts
  -they are a fairly cheap defence

Question 15

what are the disadvantages/costs of groynes?

Answer 15

-they starve beaches further down the coast of sand making them narrower
-narrow beaches do not protect the coast as well leading to greater erosion and flood

Question 16

what are the forms of coastal soft engineering?

Answer 16

-beach nourishment and reprofiling
-soft engineering

Question 17

what is beach nourishment and reprofiling?

Answer 17

sand and shingle from elsewhere (e.g. from the sea bed) or lower down the beach that is added to the upper part of beaches

Question 18

what are the advantages of beach nourishment and reprofiling?

Answer 18

-it creates wider beaches which slow down waves
-this gives greater protection from flooding and erosion

Question 19

what are the disadvantages/costs of beach nourishment and reprofiling?

Answer 19

-taking material from the sea bed can kill organisms like sponges and coral
-it is a very expensive defence and has to be repeated

Question 20

what is dune regeneration?

Answer 20

creating or restoring sand dunes either by nourishment or planting vegetation to stabalise the sand (make sure the sand won’t drift or move)

Question 21

what are the advantages of dune regeneration?

Answer 21

-sand dunes provide a barrier between land and sea
-wave energy is absorbed which prevents flooding and erosion
-stabalisation is cheap

Question 22

what are the disadvantages/costs of dune regeneration?

Answer 22

-the protection is limited to a small area
-nourishment is very expensive

Question 23

What is meant by managed retreat?

Answer 23

1)Managed retreat involves removing current defences and allowing the sea to flood the land behind.
2)Over time the land will become marshland, which then protects the land behind it from flooding and erosion.

Question 24

What are the advantages of managed retreat?

Answer 24

-It is a cheap and easy strategy, and it doesn’t need maintaining.
-The marshland can create new habitats for plants and animals.

Question 25

What are the disadvantages of managed retreat?

Answer 25

it can cause conflicts, e.g. flooding farmland affects the livelihood of farmers and saltwater can have a negative effect on existing ecosystems.