Sea Defences

Question 1

What are the 5 types of hard engineering?

Answer 1

Sea wall
Rock revetments/armour
Gabions
Groynes
Breakwater

Question 2

What are the 2 types of soft engineering?

Answer 2

Manage retreat

Beach replenishment

Question 3

What are the advantages and disadvantages of a sea wall?

Answer 3

Lasts 75 years on average
Creates a promenade

Slows down deposition
Very expensive

Question 4

What are the advantages and disadvantages of rock armour/rip rap?

Answer 4

Arguable that it looks more natural than other sea defences
Last a long time

Can be a danger to people who are passing or children playing etc
Expensive
Restricts access to beach potentially
Less beach - less tourism

Question 5

What are the advantages and disadvantages of groynes?

Answer 5

Creates a much deeper beach (on one side)

Eye sore
High maintenance is needed
Doesn't last long
Quite expensive
Other side of groyne gets less deposited material

Question 6

What are the advantages and disadvantages of wooden revetments?

Answer 6

Absorb a lot of wave energy

Makes access to the beach difficult
Eye sore
Expensive

Question 7

What are the advantages and disadvantages of gabions?

Answer 7

Cheap to build and replenish
Look quite natural
Doesn’t affect LSD so the beach can be maintained

Must be maintained regularly
Don’t last that long
Water can seep through gaps

Question 8

What are the advantages and disadvantages of beach replenishment?

Answer 8

Creates a nice and deep beach = more tourism = more money

Can kill sea life if material is extracted from the sea bed
Must be maintained a lot
Doesn’t last long at all
Expensive

Question 9

What are the advantages and disadvantages of manage retreat?

Answer 9

Doesn’t cost anything
Natural

Erosion will occur quicker compared to using sea defences