Managing risks and conflicts Flashcards
Definition of hard engineering
building structures along coast (usually at the base of a cliff or beach)
-looking to prevent erosion
Name 2 disadvantages of hard engineering
- high costs
- coastlines made visually unattractive
Definition of soft engineering
designed to work with natural processes in coastal system to manage not necessarily prevent erosion
What is a cost-benefit analysis
process carried out before a coastal management project is given the go-ahead
What is a cost-benefit analysis
tool used to help decide whether defending a coastline from flooding and/ or erosion is ‘worth it’
Definition of tangible
where costs and benefits are known and can be given a monetary value (building costs)
Definition of intangible
where costs may be difficult to assess but are important
What is an environmental impact assessment
process that aims to identify:
- short-term impacts on the coastal environment construction
- long-term impacts of building new sea defences
What does an environmental impact assessment include assessments of
- impacts on water movement and sediment flow- could affect marine ecosystems due to sediment load
- impacts on water quality- could affect sensitive marine species
- possible changes to flora and fauna (marine plants, fish, shellfish, marine mammals)
- wider environmental impacts: air quality, noise pollution- during construction
Name the 4 approaches to coastal management
- hold the line- existing coastal defences are maintained (sea wall/ rock armour)
- advance the line- build new defences out at sea –> reduce stress on current defences
- retreat the line- move people out of danger zones behind new line of coastal defence
- do nothing- deal with effects of flooding as they come/ ignore them
What is terminal groyne syndrome
where higher rates of erosion occur immediately after a set of coastal defences have finished
Give an example of a place where terminal groyne syndrome has occurred
groynes built at Hornsea to protect the town starved Mappleton (further down) of sediment
Name 3 issues for residents living along the Holderness coastline of which erodes at 2m per year
- falling property values
- loss of access of roads, paths
- inability to sell their property- possibility of loss to erosion
Meaning of an economic loss
Loss of (or damage to) property : homes, businesses, farmland,
Meaning of a social loss
impacts on people: relocation, loss of livelihood (job), impacts on health
Meaning of an environmental loss
loss of coastal ecosystems, habitats
Name 3 reasons why economic losses from erosion are localised and small
- erosion is incremental -> small no of properties affected over long period
- properties at risk lose value before destroyed -> potential buyers recognise risk
- high populated areas -> protected by defences -> reduces erosion
Name 3 issues those living on the Holderness Coastline which erodes 2m per year face (economically)
- falling property values
- inability to sell proerpties
- loss of their major asset and cost of getting a new home
Name 3 issues those living on the Holderness Coastline which erodes 2m per year face (socially)
- loss in amenity value -> coastline visually scarred -> loss of tourism, community
- loss of access to roads, paths
- increased cost to owners of cliff-top caravan parks -> have to keep moving caravns -> relocation -> stress
Give the cause, economic cost and social cost of the North Sea flood in Netherlands, 1953
Cause -> mid-latitude depression moving south through North Sea generating a 5m storm surge
economic cost: almost 10% of Dutch farmland flooded
40,000 buildings damaged
10,000 buildings destroyed
social cost: 1800 deaths
Give the cause, economic cost and social cost of the UK 2013-14 (Winter Storms)
Cause- by coastal and other flooding from a succession of depressions and their storm surges
economic cost- damage of £1 billion
social cost - 17 deaths
What are environmental refugees
those forced to leave their homes because of natural processes (landslides/ erosion/ rising sea levels)
Name 2 advantages of hard engineering
- reassuring -> somethings being done to portect those at risk
- ‘one off’ solution -> can protect coastline for decades
Name the 5 different types of hard engineering
Groynes Sea Wall Rip Rap (rock armour) Revetments rock breakwater
What are groynes and what are there purposes
-vertical stone or timber ‘fences’ -> perpendicular to coast -> spaced along the beach
prevent longshore drift
encourage deposition -> wider, higher beach.
Explain 2 advantages and disadvanategs of groynes
+deposition- builds up beach- increases tourism
+not too expensive
- starve beaches further along coast- terminal groyne syndrome
- unnatural
What are sea walls and what are there purposes
made of steel/ concrete - at foot of cliff or top of beach- usually curved
- physical barrier against erosion
- flood barriers
- dissipate wave energy
Explain 2 advantages and disadvantages of groynes
+effective prevention of erosion
+often have promenade for ppl to walk on
- unnatural
- expensive to build & maintain
What are rip rap and what are there purposes
Large rock boulders placed at bottom of cliff/ top of beach
- break up and dissipate wave energy
- prevent undercutting of cliff
Explain 2 advantages and disadvantages of rip rap
+relatively cheap
+can be used to sunbathe/ fish on
- intrusive
- can be dangerous for ppl clambering on them
What are revetments and what are there purposes
sloping wooden, concrete/ rock structures- placed at foot of cliff/ top of beach
- absorb wave energy
- reduce swash distance -> encourage inflitration
- Reduce erosion on dune faces and mud banks
Explain 2 advantages and disadvantages of revetments
+inexpensive to build
- intrusive
- can need high levels of maintenance
What are rock breakwaters and what are there purposes
submerged rock barrier
-forces waves to break offshore, rather than at the coast -> reducing wave energy and erosive force
Explain 2 advantages and disadvantages of rock breakwaters
+effective permeable barrier
- unappealing
- potential navigation hazard
Name 2 advantages of soft engineering
- cheaper in long term
- less obvious and intrusive at coast
Name 2 disadvantages of soft engineering
-not suitable for all coasts
Name the 3 types of soft engineering
Beach Nourishment
Cliff Regrading and Drainage
Dune stabilisation
What is beach nourishment and what is its purpose
addition of sand/ pebbles to an existing beach -> higher and wider
-to replace sediment lost by erosion
- to enlarge beach
- > dissipates wave energy and reduces erosion
Explain 2 advantages and disadvantages of beach nourishment
+cheap and easy to maintain
+natural looking
-needs constant maintenance due to erosion, longshore drift
What is Cliff Regrading and Drainage and what is its purpose
cliff regarding- reducing angle of cliff -> stablise it
drainage- removes water -> prevent landslides, slumping
to keep cliffs stable
Explain 2 advantages and disadvantages of Cliff Regrading and Drainage
+drainage is cost-effective
+regrading works where other methods dont: on clay, loose rock
- regrading causes cliff to retreat
- drained cliffs -> dry out -> collapse
What is Dune stabilisation and what is its purpose
when marram grass is planted to stabilise dunes
-> reduces erosion by wind and water.
Explain 2 advantages and disadvantages of Dune stabilisation
+provides habitats
+cheap and sustainable
-time consuming to plant marram grass
Name 6 forms of sustainable coastal management
Managing natural resources (fish, farmland, water supply) to ensure long-term productivity
Managing flood and erosion risk where possible, or relocating to safe areas
Creating alternative livelihoods before existing ones are lost to the sea
Adapting to sea level rise by relocating, alternative building methods and water supplies
Educating communities to understand why change is needed and how to adapt
Monitoring coastal change and adapting to unexpected trends
Name 4 reasons why sustainable coastal management causes conflict
disagreement over how coast should be protected from threats
people are forced to relocate
some erosion and flooding will always occur (unable to divert/protect)
future sea level rise is uncertain, so plans may be altered
Give 2 reasons as to why adopting sustainable coastal management may lead to conflict
coastal natural resources -> used to less in order to protect them -> some ppl lose income
future trends, such as sea level rise, may change, -> uncertainty -> change plan.
What are the economic losses from coastal recession?
housing
businesses
agricultural land
infrastructure
What are the social losses from coastal recession?
relocation
loss of livelihood
amenity value
What are the environmental losses from coastal recession?
loss of coastal ecosystems and habitats
What are the social, economic and environmental losses due to recession on the Holderness Coast?
SOCIAL - 30 villages lost since Roman times, many are reliant on tourism, potential loss of livelihood
ECONOMIC - visitor numbers dropping, 80,000 m2 of farmland is lost each year, it is predicted 200 homes and roads will fall into the sea by 2100
ENVIRONMENTAL - Spurn Head losing diversity due to sediment erosion, sites of specific scientific interest being destroyed
Why is erosion a problem for the Holderness coast?
Longshore drift - material moved through sediment cell
Geology - made of unconsolidated boulder clay which is easily eroded (glacial period deposits), little resistance
Fetch - 500 to 800km fetch means more destructive waves
What are the different coastal hard engineering strategies?
groynes
sea walls
rip rap/rock armour
revetments
offshore breakwaters
What are the coastal soft engineering strategies?
beach nourishment
cliff stabilisation/regrading
dune stabilisation
What is sustainable coastal management?
Managing the wider coastal zone in terms of people and their economic livelihoods, social and cultural wellbeing and safety from coastal hazards, as well as minimising environmental and ecological impacts
What must be included within sustainable coastal management?
managing natural resources
managing flood and erosion risk
creating alternative livelihoods before existing ones are lost
adapting to sea level rise by relocation
educating communities
monitoring coastal change
What is ICZM?
Integrated coastal zone management
Holistic approach that involves all stakeholders
What are the 3 key characteristics of ICZM?
entire coastal zone managed - all ecosystems, resources and human activity
recognises importance of coastal zone to people’s livelihoods
management must be sustainable and ‘environmentally appropriate’
What is a littoral cell?
All coastlines divide up into these ‘cells’ which contain sediment sources, transport paths and sinks. Each cell is managed as an integrated unit by a SMP
What is a SMP?
Shoreline Management Plan
-created to help with coastal management
-identifies physical, human activity within coastline area of each sediment cell
What are the 4 policies available for coastal management in the UK?
No active intervention: land allowed to flood/eroded with no actions taken
Strategic (managed) realignment: coastline allowed to move naturally, but ‘directed’ in certain areas
Hold the line: build/maintain coastal defences
Advance the line: build new coastal defences seaward of existing coastline, often involves land reclamation
What is cost-benefit analysis?
A process used to help decide if defending a coastline is economically justifiable
-benefits must outweigh costs for project to be given go ahead
Name the 3 organisations responsible for coastal decision making
-CBA- cost benefit analysis
-ICZM- integrated coastal zone management
-SMPs - shoreline management plans
What is an EIA?
Environmental Impact Asessment
A process that aims to identify short term impacts on environment from construction and the long term impacts of building new defences/changing policy
What strategies have been used in the Holderness Coast’s SMP?
Some areas are ‘hold the line’ but others are ‘do nothing’
£2 million groyne at Mappleton in 1992 - impacts on Great Cowden (do nothing)
Easington 1km long revetment
Hornsea 1.86km of concrete sea walls
How effective is management on the Holderness Coast?
The artificially defended locations create non-eroding ‘hard points’ which interrupt natural processes (dynamic equilibrium of sediment cell)
This will create new bays and ‘headlands’ as beaches reorient themselves
Terminal groyne syndrome – starving one beach of sediment because of groynes
Give 3 examples of winners created as a result of coastal management
-groynes -> protect valuable infrastructure (hotels, cafes, houses) -> encourage tourism, protect livelihoods
-larger beach -> protects backshore habitats -> ^ biodiversity -> happy environmental pressure groups
-offshore breakwaters -> decrease wave energy -> reduces erosion risk -> safeguards properties
GIve 3 examples of losers created by coastal management
-sea walls -> visually unappealing & high cost -> may detract tourists
-groynes -> terminal groyne syndrome -> strave areas downstream of sediment -> ^ coastal recession in these areas
