3.4- coastal management

Question 1

What proportion of the world’s population live within 60km of the coast (and 3/4 of all large cities are at the coast) - UNEP

Answer 1

Half

Question 2

Some coastal landscapes including human and natural environments are coming under increasing pressure from

Answer 2

Both natural processes and human activities

Question 3

Due to coastal landscapes coming under increasing pressure, a range of

Answer 3

Protection and management strategies have been put in place by many coastal areas (these solutions are often successful but in some cases, the solutions themselves

Question 4

Coastal management has 2 main aims:

Answer 4

• to provide defence against, and mitigate the impacts of flooding
• to provide protection against, and mitigate the impacts of coastal erosion

Question 5

What are the other aims of coastal management apart from its two maim aims?

Answer 5

• stabilising beaches affected by LSD
• stabilising sand dune areas
• protecting fragile estuarine landscapes

Question 6

Management strategies can work work either with or against

Answer 6

Natural processes

Question 7

Management strategies of working with nature means

Answer 7

Allowing the natural processes of erosion to occur (managed retreat) and not spending money on the defence of the costal area- this is now applied to large stretches of coastline in the UK where there are few settlements (soft engineering techniques such as beach nourishment are said to work with nature)

Question 8

Management strategies working against nature usually occurs where there is

Answer 8

Significant capital investment (buildings and communications) in the coastal region that has to be protected- protection involves constructing sea walls, revetments,groynes and other examples of hard engineering- the cost of such defences are justified by the potential expense of replacing sea-damaged buildings and infrastructure of try were not in place

Question 9

Traditional approaches to coastal erosion and flood risk include

Answer 9

Hard and soft engineering

Question 10

What is hard engineering?

Answer 10

Hard engineering involves the building of entirely artificial structures using various materials such as rock, concrete and steel in order to reduce or stop the impact of coastal processes

Question 11

What are examples of hard engineering?

Answer 11

• sea walls
• rock armour
• gabions
• revetments
• groynes
• cliff fixing
• offshore reefs
• barrages

Question 12

What are sea walls and what do they do?

Answer 12

• The sea wall is a concrete barrier along the coast which aim to dissipate wave energy
• the recurved structure throws waves back out to sea, into the path of the next incoming wave, thus also reducing its wave impact
• also provide physical barrier to flooding by raising height of coastline
• sea walls must have a continuous facing because any slight gal will be exploited by hydraulic action
• they also need drain outlets so that any water that does get over them, does not accumulate inland

Question 13

What are the evaluation points for sea walls?

Answer 13

✅Sea walls are very effective at protecting the coastline and will prevent erosion, as long as they are maintained and repaired.

❌The maintenance and repairing can be very expensive.

❌The initial cost to build them is also expensive (approx £6000 per meter).

✅They last around 100 years, however often deflecting the waves can make the base of the wall weak and therefore they require constant maintenance throughout this period.

❌ The sea wall also looks quiet unattractive and not natural = people may complain of visual pollution to beautiful beaches which may have detrimental effects on tourism

Question 14

What is rock armour and what does it do?

Answer 14

• rock armour (rip-rap) consists of large (often granite or other hard rock) boulders dumped in front of a cliff or sea wall to take the full force of the waves
• the boulders are deliberately left in angular appearance to present a large surface area to the waves, and create gaps for water to filter through, again mitigating their impact on the coast
• usually the boulders are not secured in place so energy is taken out of the most powerful waves by rocking or slightly moving the massive rocks

Question 15

What are the evaluation points for rock armour?

Answer 15

✅These are relatively cheap at £1000 per meter and lasting around 120 years. They also use natural resources-rocks.

❌ often perceived that they’re an “eye sore” to beautiful coast

Question 16

What are gabions?

Answer 16

Gabions operate in the same principle as rip-raps, but smaller boulders are contained with steel wire-mesh cages, each of which can be joined together to form larger structures or walls

Question 17

What are revetments and what do they do?

Answer 17

Revetments are a sloping concrete or wooden structures placed across a beach or coastline to take the full force of the wave energy, preventing further erosion of the coast

Question 18

What are the evaluation points for revetments?

Answer 18

❌They are less durable than a sea wall and so may need replacing quicker.
❌They also do not give total protection to the base of the cliff, and will need replacing faster than a concrete sea wall.
❌They cost up to £4500 per metre

Question 19

What are groynes and what do they do?

Answer 19

• wooden, stone or steel breakwaters buoy newest at right angles to waves (usually 5 degrees-10 degrees from the perpendicular to prevent scouring on the down-drift side of the groyne)
• built to reduce the rate at which LSD carries material along the beach by trapping sediment on one side
• this extra beach is then able to protect the coast from the sea

Question 20

What are the evaluation points for groynes?

Answer 20

❌ halting the bulk of LSD in an area may have serious effects down the coast where it will cut off the supply of beach material and could leave the coast there exposed to erosion
✅ average life span around 30-40 years
✅ relatively cheap at around £1000 per metre if wooden and £1000 per cubic metre for rock

Question 21

What are off shore break waters?

Answer 21

• off shore break waters are built parallel to the coast, off the coast from rock
• waves are forced to break before they reach the shore, thus reducing the wave energy

Question 22

What are the evaluation points for off shore break waters?

Answer 22

❌They are very expensive at around 1.3 million pounds for one, however effective at reducing the energy of the waves and thus their impact on base of cliffs (mitigating hydraulic action)

✅ As they are out to sea they do not spoil the beach (not an ‘eye sore’ )
-However being out at sea means they can be tricky to maintain

Question 23

What does soft engineering involve?

Answer 23

Soft engineering used natural systems for coastal defence, such as beaches, dunes and salt marshes, which can absorb and adjust to wave and tide energy- it involves manipulating and maintaining these systems, without changing their fundamental structures

Question 24

What are the different soft engineering strategies?

Answer 24

• beach nourishment
• dune regeneration
• managed retreat
• cliff regarding and drainage
• do nothing

Question 25

What does beach nourishment involve?

Answer 25

process by which sand is replaced along the beach.

• replenishing the beach makes the beach more effective at dispersing the energy of the waves.
• It replaces the material lost by longshore drift
• it does not prevent longshore drift so has to be done repeatedly, making it expensive

Question 26

What are the evaluation points for beach nourishment?

Answer 26

❌It is done so through taking material from the sea bed and dumping it onto the shore; this involves the use of a dredger which is noisy and upsets tourism and kills marine life from the sea bed.
✅It is attractive –the beach looks untouched.

Question 27

What does dune regeneration involve?

Answer 27

• the fragile sand dune environment is easily disrupted by human activities
• most damage is caused by the removal of vegetation by either agriculture (overgrazing) or tourism (trampling the dunes)
• management strategies to regenerate sand dunes include:
  1- replanting vulnerable areas with plants such as marram grass
  2- afforestation with quick-growing conifers
  3- restricting access by fencing off areas
  4- providing boardwalks for tourists
  5- educating locals and tourists on potential damage

Question 28

What does managed retreat involve?

Answer 28

• involves allowing the coast to take back the land, by removing existing sea defences and allowing the land behind them to flood.
• overtime the land will become marsh land allowing habitats to form
• the marshland will also act as a natural sea defence protecting the land behind it from erosion

Question 29

What are the evaluation points for managed retreat?

Answer 29

✅ fairly cheap sea defence
❌ Managed retreat allows land to flood and become eroded and some people may not agree over which land should be flooded. This causes conflict

Question 30

What are the evaluation points for dune regeneration/stabilisation?

Answer 30

✅Maintains a natural coastal environment.
✅Provides wildlife habitats
✅Cheap and sustainable

Disadvantages:
❌Time consuming
❌May still be eroded if people ignore signs and fenced off areas.

Question 31

What does cliff regarding and drainage involve?

Answer 31

Reducing the angle of a cliff to stabilise it. Drainage removes excess water to prevent landslides and slumping.

Question 32

What are the evaluation points for cliff regarding and drainage?

Answer 32

✅Very effective on clay or loose rock cliffs

Disadvantages:
❌Draining of the cliff can dry it out too much and cause it to crumble and collapse.
❌Some homes on the cliff may need to be demolished as it effectively causes retreat

Question 33

What does ‘do nothing’ involve?

Answer 33

• In the first decade of the 21st century, a school of thought has grown up that asks whether the coast should be protected
• tens of millions of pounds are spent annually in the UK on coastal protection; it may be cheaper in some cases to let nature take its course and pay compensation to those affected
• the storms of December 2013 and January 2024 illustrated how trying to control the power of nature is often futile, with the traditional hard sea defences of Aberystwyth in West Wales for example, providing ineffective against the powerful wind and waves
• some argue that the limited funds available for coastal protection should be targeted to places like this that have significant infrastructural or economic value for large numbers of people—> this debate is not new however; the House of Commons select committee on Agriculture suggested in 1998 that large tracts of land should be ‘surrendered to the sea’ as trying to protect them is a waste of money. Obviously, those living in places deemed not worthy of protection may view the debate quite differently

Question 34

Increasingly, managements authorities – both political and non-political – are looking at ______ management plans for significant stretches of coastline

Answer 34

Holistic

Question 35

What does a holistic management plan for coastlines entail?

Answer 35

A holistic approach means that the entire coastal zone is included in management plans – instead of just short stretches of coast. It is a long term approach that looks to achieve a balance between natural processes and human concerns

Question 36

Holistic management of coastlines is achieved in 2 ways:

Answer 36

• Shoreline Management Plans (SMP)

- Integrated Coastal Zone Management (ICZM)

Question 37

Around England and Wales there are __ Shoreline Management Plan (SMP) which cover the 11 sediment cells previously identified

Answer 37

22

Question 38

Explain the aim of SMP

Answer 38

• SMP is a plan for managing flood and erosion risk for a particular stretch of shoreline, looking at the immediate, medium and long term
• main aim of SMP is to develop a sustainable management approach (actions that do not cause problems elsewhere) for the shoreline that takes account of the key issues and achieved the best possible balance of all the values and features that occur around the shoreline over the next 100 years- this needs to recognise the strong relationship with social, economic and environmental activities around the shoreline= SMP policies therefore have to be realistic

Question 39

Regarding SMP, four options are considered for any stretch of coastline:

Answer 39

1. Hold the line – maintaining the current position of the coastline (often using hard-engineering methods).
2. Advance the line – extending the coastline out to sea (by encouraging the build-up of a wider beach, using beach-nourishment methods and groyne construction.
3. Managed retreat/strategic realignment – allowing the coastline to retreat in a managed way (e.g. creating salt-marsh environments by deliberately breaching flood banks that protect low-quality farmland.
4. Do nothing/no active intervention – letting nature takes its course and allowing the sea to erode cliffs and flood low-lying land and allowing existing defenses to collapse

Question 40

What does ICZM aim to do?

Answer 40

ICZM aims for the coordinated application of the different policies affecting the coastal zone and related to activities such as nature protection, agriculture, tourism and mitigation and adaption to climate change

Question 41

Why is ICZM often referred to as the ‘ecosystem-based approach’?

Answer 41

It will contribute to sustainable development of coastal zones by the application of an approach that respects the limits of natural resources snd ecosystems = the so called ‘eco-system based approach

Question 42

ICZM covers the full cycle of

Answer 42

information collection, planning, decision-making, management and monitoring of implementation- it is important to involve all stakeholders across the different sectors to ensure broad support for the implementation of management strategies

Question 43

For the well-being and economic prosperity of many coastal communities the condition of the natural environment is often crucial, therefore officials believe the long-term plans proposed by ___ are vital to ensure sustainable development for generations to come

Answer 43

ICZM

Question 44

Why is ICZM designed to integrate the interests of all stakeholders?

Answer 44

• in the past, coastal management was often viewed as having a sectoral approach, where the local authorities made decisions for their stretch of coastline and other agencies and interest groups tried to manage their particular environment, cause or social group
• in the view of the European Commission this led to decisions that undermined each other, an inefficient use of resources and failure to meet sustainability objectives
  = why ICZM is designed to integrate the interests of all stakeholders to avoid such problems

Question 45

Summarise the key features of ICZM:

Answer 45

• monitoring, measuring and recording what is taking place at the coast
• involving all interested parties
• holistic
• planning collaboratively with all stake-holders
• working with natural processes
• sustainability