Coastal management stategies

Question 1

What is hard engineering?

Answer 1

Man-made structures built to control the flow of the sea and reduce flooding and erosion

Question 2

What is soft engineering?

Answer 2

Schemes set up using kmowledge of the sea and its processes to reduce the effects of flooding and erosion.

Question 3

Sea wall

what is it and pros and cons

Answer 3

A wall made out of hard material like concrete that reflects waves back to sea
* It prevents erosion of the coast. It also acts as a barrier to prevent flooding
* It creates strong backwash that erodes under the wall. Expensive to build and maintain

Question 4

Gabions

Answer 4

A wall of wire cages filled with rocks, usually built at the foot of cliffs.
* Gabions absorb wave energy and so reduce erosion. They’re cheap and easy to build
* * * They’re ugly to look at and the wire cages corrode over time

Question 5

Rock armour

Answer 5

Boulders that are piled up along the coast (sometimes called rip-rap)
* It absorbs wave energy, reducing erosion and flooding. Its a fairly cheap defence
* Boulders can be moved around by strong waves, so they need to be replaced

Question 6

Groynes

Answer 6

Wooden or stone fences that are build at right angles to the coast. They trap material transported by longshore drift
* They create wider beaches whivh slow the waves. This gives greater protection from flooding and erosion. They’re a fairly cheap defence
* They starve beaches further down the coast of sand, making them narrower. Narrower beaches dont protect the coast very well leading to greather erosion

Question 7

Beach nourishing and reprofiling

Answer 7

Sand and shingle from elsewhere or from lower down the beach thats added to the upper part of beaches
* It creates wider beaches which slows the waves. this gives greater protection from flooding and erosion
* Taking material from the seabed can kill organisms like sponges and corals
* Its very expensive defence and has to be repeated

Question 8

Dune Regeneration

Answer 8

Creating or restoring sand dunes by nourishment, or by planting vegetation to stabilise the sand
* Dune create a barrier between land and sea and absorb wave energy, preventing flooding and erosion. stabilisation is cheap
* The protection is limited to a small area. Nourishment is very expensive