Objectives

To identify and describe the different types of coastal management available.

To evaluate the positives and negatives of each option.

How do we manage coastlines?

QUESTION: Why do we need to manage coastlines? (answer in bullet points in your book)

Should we protect ?

What coastal defences do you know of already?

Add to this list from what you see in the video.

http://www.bbc.co.uk/learningzone/clips/coastal-management-strategies-sea-defences-and-managed-retreat/3243.html

Coastal Management

1.Match the pictures on the board to the correct definition and defence-type

2. Are they hard or soft engineering?

3. Write down the positives and negatives for each type of management (think environmental, economical, visual, social)

12

3 4

5

6

Hard and soft engineering• Soft Engineering• Soft engineering approaches are less expensive, are more long

term, attractive and sustainable as they work with natural processes.

• Hard Engineering• Hard engineering approaches tend to be expensive, last only a short

amount of time, are visually unattractive and unsustainable. They often increase erosion in other places further down the coast.

http://www.geography.learnontheinternet.co.uk/topics/coastal_management.html#Soft_techniques

Defence Option POSTIVES NEGATIVES (think Environmental, Economical, Visual)

Recurved Lip

Groynes

Gabion

Revetment

Rip Rap

Beach Replenishment

For each of the different methods below, you must outline the positive and negative aspects of each type of defence

Cost Economic Impact

(how business/tourism

is effected)

Environmental Impact

the coastline/natural beauty/habitats

Social Impact

how humans lives could be affected

YOUR OPINION - How effective do

you think the defence?

(score from 1-6)

TOTAL

Curved Sea Wall

Groynes

Gabions

Revetments

Rip Rap

Beach Nourishment

CHALLENGE TASK- On a scale from 1 to 6 (1 = very bad/expensive/many negative effects and 6 = very good/cheap/most positive effects), you must score each solution based on Cost, Economic Impact, Environmental Impact, Social Impact and How Effective each defence is, giving an overall total for each solution.

RevetmentsThese are wooden posts with slats of concrete laid on top of the beach to stop the sand being eroded.They are cheaper than sea walls, but do not last long where the waves have lots of energy.

GroynesNatural beaches are the best sea defence, but often they are washed away by longshore drift. Groynes are cheap fences made from large wooden posts. They trap the sand and stop the beach being washed away. (look at the beach height either side of the groyne!)

Beach ReplenishmentSometimes it is necessary to replace the sand and shingle that has been lost by the action of the sea. Lorries are used to transport material dredged up from the sea bed to the beach.

Curved Sea WallA wall with a rounded lip at the top. This breaks up the waves energy and reflects the waves back into the sea, stopping them going over the top. Expensive but last for a long time.

GabionsMetal cages filled with rocks. They are stacked together to make a wall to protect the coast.They are much cheaper than other sea defenses but don’t last as long.

Rip RapThese big boulders are usually placed at the bottom of a cliff. As the waves hit the boulders, their energy is lost so their erosive power is reduced. They are expensive.

RevetmentsThese are wooden posts with slats of concrete laid on top of the beach to stop the sand being eroded.They are cheaper than sea walls, but do not last long where the waves have lots of energy. Cost - £320,000 per 100 metres for 20 years

GroynesNatural beaches are the best sea def ence, but of ten they are washed away by longshore drif t. Groynes are cheap fences made from large wooden posts. They trap the sand and stop the beach being washed away. (look at the beach height either side of the groyne!)Cost - £90,000 per 100 metres for 20 years

Beach ReplenishmentSometimes it is necessary to replace the sand and shingle that has been lost by the action of the sea. Lorries are used to transport material dredged up from the sea bed to the beach.Cost - £160,000 per 100 metres for 20 years

Curved Sea WallA wall with a rounded lip at the top. This breaks up the waves energy and reflects the waves back into the sea, stopping them going over the top. Expensive but last for a long time.Cost - £700,000 per 100 metres for 20 years

GabionsMetal cages filled with rocks. They are stacked together to make a wall to protect the coast.They are much cheaper than other sea def enses but don’t last as long.Cost - £50,000 per 100 metres for 20 years

Rip RapThese big boulders are usually placed at the bottom of a cliff . As the waves hit the boulders, their energy is lost so their erosive power is reduced. They are expensive.Cost - £132,000 per 100 metres for 20 years

Now, using the 6 statements from different people, and the information from the previous task;

You need to complete the POSITIVES and

NEGATIVES table for each of the defence types, giving reasons for your opinions

Council EngineerI believe that something has to be done to sustainably

protect our shores. I believe in aiming to please everyone and to protect property, farmland and to make the beach and

cliffs safe for the public and tourists. Plus, an increase in local economic growth will result from the defences being built as

jobs are created too, as well as the continued futures of current businesses and homes being secured.

Professor of GeographyI think that expensive defences will not help solve the

problem. One of the biggest causes of erosion are mudslides caused by over saturation of the soil. Also, heavy

storms can cause severe damage to any hard structures that are built. Also, the quality of the beaches at may

become degraded over time, looking muddy and grey, as less sediment is transported along the shore. Beach levels

could fall, allowing the cliffs to become more susceptible to erosion.

Local Resident – Locals Against Coastal ErosionAfter I retired, I decided to move back to where I spent

my childhood and set up a small bed and breakfast. The coastal scenery was perfect for attracting tourists.

But now, the coastline is littered with debris from fallen buildings and landslides. Something must be done to help protect our livelihoods, as our village is slowly

becoming closer to the cliff edge day by day.

Hotel ManagerThe views from my hotel of the sandy beach and the

coastline are fantastic, and are a real money-spinner for me. Sure, there are some defences in place already, but they do

not spoil the scenery. I didn’t realise that if defences are built further up the coast, this will effect the shape of my

beach for years to come. Longshore Drift I think they call it? Plus, my insurance premium would increase as the risk of

cliff collapse is higher!

TouristI have mixed feelings about this issue. I was at

first against the idea of ugly defences cluttering up the coast I grew up to love when visiting as a child. But now I have made friends here, to see

them loose their homes and in some cases businesses makes me lose sleep. Of course there

are more “natural” options, but what with climate change raising sea levels, will these

“softer” options be strong enough?

ConservationistI am very much against there being any further defences to be built in this area. There is SO much rare wildlife and scientifically important

habitats that the harbour is now an SSSI (Site of Special Scientific Interest). I believe that nature should be allowed to follow its own course, without human interference. After all, the animals and the

landscape have been around for a much longer time than us humans (and no doubt will be here long after us too).

BIPOLAR EVALUATION OF SEA DEFENCESNEGATIVE EVALUATION FACTOR -3 -2 -1 1 2 3 POSITIVE EVALUATION FACTOR

Vulnerable to erosion (unable to 'hold the line') Effective protection against erosion (able to

'hold the line')

Vulnerable to overtopping (unable to control flooding) Effective against overtopping (good flood

defence)

Ugly (poor aesthetic value) Enhances natural environment (high aesthetic value)

Poor access to beach Good provision made for access to beach

High risk safety hazard to general public No obvious safety risk to general public

Short lifespan &/or high maintenance costs Good life expectancy &/or low maintenance costs

High levels of disturbance caused to local people during construction Low levels of disturbance caused to local

people during construction Disturbs natural coastal processes & habitats Maintains natural coastal processes &

habitats

A more advanced bi-polar – needs one per defence type

Final thoughts....

In your groups, you will see a picture as if you were a news reporter live on the scene.

You have to come up with a 20 second news-byte to summarise what the poeple at each location would think about the plans to manage the coastline

Our Coasts are Eroding!!

1 2 34 5 67

Town Hall

City Insurance

University

Disgruntled Hotel Owner

Worried Tourist

Conservationist on the salt marshes

Worried local resident