Hard engineering structures

Question 1

How does a sea wall work, what the cost and disadvantages?

Answer 1

Reflects waves back out to sea, preventing erosion of the coast. Acts as a barrier to prevent flooding
Expensive to build and maintain
Creates strong backwash which erodes under the wall

Question 2

How do Gabions work, what the cost and disadvantages?

Answer 2

Rock filled cages at the foot of cliffs and absorbs wave energy and reduces erosion.
Cheap
Ugly

Question 3

How do breakwaters work, what’s the cost and disadvantages?

Answer 3

Concrete blocks deposited off the coast. Force waves to break offshore. Waves energy and erosive power is reduced
Expensive
Can be damaged in storms