Engineering Managment Approaches

Question 1

Coastal defences - HE

Answer 1

HE strategies aim 2 reduce the effects of flooding + erosion by building man-made structures that control the sea’s flow

Question 2

Sea walls

Answer 2

Are made out of hard concrete that deflects waves. They’re often curved to dissipate the waves energy + refract it back towards the sea
They’re good LT solution because of the resistance of concrete leading 2 less maintenance
But create a strong backwash that can undercut the wall + they are expensive 2 build + maintain

Question 3

Rip-rap

Answer 3

Pile of boulders
Often placed in front of sea walls 2 dissipate the waves energy + support unstable rock structures
Long lasting + relatively cheap
Provide a hazard for ppl accessing the beach + have gaps between the rocks allowing erosion + weathering 2 continue

Question 4

Revetments

Answer 4

Angled walls placed just offshore 2 assist in breaking down the force of the waves 2 reduce their ability 2 eroide the coastline
More cost-effective technique to a sea wall + reduce the rate of erosion
Often require regular maintenance + can create access problems to the beach

Question 5

Groynes

Answer 5

Stone or wooden fences that stick out at 90degrees to the coast
Stop material being transported long distances by longshore drift
Create wider beaches which slows down waves + reduce erosion + flooding
Relatively cheap
BUT beaches further down the coast get narrower which means waves are not slowed down + erosion + flooding are more likely

Question 6

Offshore breakwaters

Answer 6

Made up of rocks placed in a line parallel to the shore
Provide calmer conditions behind the breakwater allowing the beach 2 be used safely for recreational sports
Can cause wave patterns 2 change + are expensive 2 install

Question 7

Coastal defences - soft engineering

Answer 7

SES aim 2 reduce the effects of flooding + erosion using our understanding of the sea + working sustainably

Question 8

Beach nourishment + reprofilling

Answer 8

BN + R involves moving material to the upper sections of beaches from elsewhere
Slows down waves by widening beaches + so reduces the risk of erosion + flooding
Maintains the beach for tourist use supporting the local economy
Removing sand + shingle from the seabed threatens certain organisms (corals)
Expensive + must be repeated

Question 9

Dune stabilisation

Answer 9

Involves the creation or restoration of sand dunes 2 maintain their protective position
Can be achieved through nourishment or planting vegetation
Provides a natural barrier 2 coastal flooding + can support wildlife habitats
Small area is protected + is ineffective in preventing wave action during powerful storms

Question 10

Cliff re-grading

Answer 10

C-R + drainage involves restructuring + supporting the cliff 2 prevent further collapse from weathering + mass movement processes
Maintains the cliff + provides a natural environment for plant + wildlife 2 continue to flourish
Risks associated with altering cliff profiles which can lead 2 further collapsing + unintended changes 2 the profile