- 45% of England’s coast is buttressed with sea walls, groynes or artificial beaches
Hard
Engineering:
- Involves some type of building (using hard materials like wood and rock)
- Blackpool spent £62 million on a sea wall and it is £3000 per metre to repair
- Examples include: Groyne, Wood or steel piling, concrete walls, wooden revetment, recurves steel wall, Gabion, rip-rap.
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Positives & Negatives of Hard Engineering:Positives:Negatives:Protection against erosion so recession stopsCosts are expensiveControls and reduces flooding so houses and towns are protectedImpacts the environmentImproves urban landscapeInterferes with sediment (starvation)Socially sustainableUnsightlyNeeds repairing which is expensive
Soft
Engineering:
- Uses soft, natural resources such as sand, sand dunes or changing cliffs and land
- Examples include: Beach nourishment, cliff regrading and drainage, dune stabilisation.
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Positives & Negatives of Soft Engineering:Positives:Negatives:Often cheaperNot effective enoughMore natural looking (amenity value)Requires natural material on land which might not be thereBetter for the environmentCould still erodeFewer ‘knock on’ effects down the coastNeeds constant managementAllows investment in other areas where hard engineering is neededSocially less accepted
Who
Manages The UK Coastlines:
- Government: Provide overall funding for coastal defence works
- Environment Agency: Scientists who decide what defences are needed
- Private Companies: Engineering firms paid to complete the work
- Local Stakeholders: They are involved in the decisions and requirement of defences.
- National Trust: Environmentalist who put pressure on bodies to care for ecosystemsHard Engineering Types:
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Blackpool’s Sea WallAdvantagesDisadvantagesReduces erosionVery expensiveInteracts with peopleEyesoreAllows for easy access to beachNeeds constant maintenance
Hornsea’s Rip-RapAdvantagesDisadvantagesAllows new habitats to formBlocks access to the beachReduces erosionAllows some erosion behind the defenceNot an eyesore and works with the coastal zone
Mappleton’s Rock GroyneAdvantagesDisadvantagesProtection of erosionSediment starvation may occurDeposition may occur insteadAllows some erosion behind the defenceRecession retreat will occur much quicker
Offshore Breakwater - NorfolkAdvantagesDisadvantagesAllows the beach to be left as it isEyesoreBuffers wavesSediment starvation can occurReduces energy of the wavesExpensive to maintain
RevetmentsAdvantagesDisadvantagesActs as a flood defenceExpensiveBuffers waveSome erosion can occurReduces energy of waveDeposition can occur behind itSoft Engineering Types:Beach NourishmentAdvantagesDisadvantagesImproves beach for touristsExpensive to maintainBuffers wavesDamages wildlife and ecosystemsReduces sub-aerial processes from occurringReduces erosion, does not stop it.
Sand Dunes - FormbyAdvantagesDisadvantagesImproves beach for tourists/doesn’t ruin oneExpensive to maintain - fencesCreates new habitatsCannot protect the coast when there is a big stormReduces erosion, does not stop it.
Cliff Regrading & DrainageAdvantagesDisadvantagesCheap to implementExpensive to maintainBuffers wavesDamages wildlife and ecosystemsReduces sub-aerial processes from occurringReduces erosion, does not stop it.
Summary: -
- Hard and Soft engineering options are available to manage coasts
- In the UK, the key players include the government, the Environment Agency, local residents, farmers and businesses.
- Hard engineering is the most effective to stop erosion and flooding for high value land, but it is also the most expensive, damaging for environment and disruptive to sediment movement.
- Soft engineering is generally cheaper, more environmentally friendly, and less impacting, but it is less viable for urban coasts and therefore socially and practically not always possible (erosion and flooding risk!)
- In reality, both hard and soft are needed for a holistic approach