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)
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). - PowerPoint PPT Presentation
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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)
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).