Coasts - EQ4 Flashcards
What is the average cost of a sea wall?
£3000-£10,000 per m.
What are the drawbacks of a sea wall?
Destroys the natural environment.
Reduces the amenity value of the beach.
Can lead to coastal squeeze of salt marshes.
What is the average cost of groynes?
£250-£2500 per m depending on if material is timber or stone.
What are the drawbacks of groynes?
Prevention of LSD leads to sediment starvation.
Increased erosion downdrift.
What is the average cost of rock armour?
£1300-£6000 per m.
What are the drawbacks of rock armour?
Reduces sediment volume being made available by erosion.
Reduced inputs = reduced outputs.
Decrease size of natural habitats.
What is the average cost of beach nourishment?
£3000 per km of beach.
What are the drawbacks of beach nourishment?
Ongoing costs are high.
If sediment is taken from elsewhere in the sediment cell, it could lead to increased erosion somewhere else.
What is the average cost of cliff stabilisation?
£1million per 100m.
What are the drawbacks of cliff stabilisation?
Very expensive.
What is the average cost of dune stabilisation?
Fencing: £400-£2000 per 100m.
Replanting: £1000 per 100m
What are the drawbacks of dune stabilisation?
Not as effective as hard engineering.
Name the 4 shoreline management plans (SMPs)
Hold the line.
Advance the line.
No active intervention.
Managed Retreat.
What policies was adopted in Holderness?
Hold the line in parts and managed retreat in others.
How long is the fetch to the Holderness coast?
1000km from Scandanavia.
