✅coasts protection

Question 1

what are the hard engineering defences?

Answer 1

sea wall
gabions
groynes
rock amour

Question 2

what is a sea wall?

Answer 2

wall made out of hard material like concrete that reflects wave energy back to sea

Question 3

adv of sea wall

Answer 3

prevents erosion

acts as barrier to prevent flooding

Question 4

dis of sea wall

Answer 4

strong backwash that erodes under the wall

expensive to build and maintain

Question 5

what are gabions

Answer 5

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

Question 6

adv of gabions

Answer 6

absorb wave energy —> reduce erosion

cheap and easy to build

Question 7

dis of gabions

Answer 7

ugly and wire cages corrode over time (rust)

Question 8

what is rock amour

Answer 8

rocks that are piled along the coast (sometimes called rip-rap)

Question 9

adv of rock armour

Answer 9

absorbs wave energy —> reduce erosion and flooding

fairly cheap

if made out of resistant rock like granite then erodes slowly

Question 10

dis of rock amour

Answer 10

boulders can be moved around by strong winds so need to be replaced

Question 11

what are groynes

Answer 11

wooden or stone fences built at right angles to the coast

trap material transported by longshore drift

Question 12

adv of groynes

Answer 12

create wider beached which slows the waves —> greater protection from flooding and erosion

fairly cheap

Question 13

dis of groynes

Answer 13

no deposition further down coast —> greater erosion

Question 14

what are the soft engineering defences?

Answer 14

beach nourishment and reprofiling

dune regeneration

Question 15

what is beach nourishment and reprofiling

Answer 15

sand and shingle from elsewhere from lower down the beach that’s added to upper part of beach

Question 16

adv of beach nourishment

Answer 16

creates wider beach —> slows waves —> greater protection from erosion and floods

beach for tourists —> generate money

Question 17

dis of beach nourishment

Answer 17

taking material from places like seabed can kill organisms like sponges and corals

very expensive defence (has to be repeated)

Question 18

what is dune regeneration?

Answer 18

creating or restoring sand dunes by nourishment or by planting vegetation to stabilises sand

Question 19

adv of dune regeneration

Answer 19

dunes can create barrier between land and sea and absorb wave energy —> prevent flood and erosion

stabilisation is cheap

Question 20

dis of dune regeneration

Answer 20

protection is limited to a small area

nourishment is expensive

Question 21

what is managed retreat?

Answer 21

removing current defences and allowing sea to flood the land which creates a marshland

this then becomes a protective strategy as the land behind marshland is protected from flooding and erosion

Question 22

adv of managed retreat

Answer 22

cheap and easy
doesn’t need maintaining
marshland can create new habitats for plants and animals

Question 23

dis of managed retreat

Answer 23

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

Question 24

where is the holderness coast located

Answer 24

east coast of yorkshire

Question 25

how much does holderness coast erode each year

Answer 25

fastest eroding coast in europe at 1.8m on average each year

Question 26

what does the holderness coast have to protect from erosion

Answer 26

groynes —> trap sand —> wider beach —> reduce erosion

sea walls —> reflect waves back to sea and prevent flooding

rock amour/riprap —> placed in front of sea wall —> reduce energy of the destructive waves

Question 27

adv of soft engineering

Answer 27

cheaper than hard engineering
usually more long term and sustainable
less impact on the environment