Coastal management involves techniques to defend coastlines against flooding and erosion. Coastlines are important for human uses like agriculture, fishing, and housing, but are constantly changing due to erosion and rising sea levels. Coastal management employs both "hard" engineering methods using materials like rock and concrete that directly resist coastal forces, and "soft" methods like beach nourishment that are more sustainable environmentally. Common hard structures are sea walls, groynes, and revetments, while soft options include beach nourishment and dune regeneration. Each approach has advantages and disadvantages in terms of cost, effectiveness, environmental impact, and maintenance requirements.

1. By Laurence Kobrock
Coastal
Management /
Protection

2. What is Coastal Management?
Coastal management is
defence against
flooding and erosion
and techniques that
allow erosion to claim
land.

3. Why do we do it?
In the case of humans, we use the coastline for
agriculture, for fishing, for industry and power
generation, for transport routes and for land upon
which to live. However, a lot of these land uses
are incompatible with the fact that the coastline is
constantly changing. Erosion processes remove
land from some parts of the coastline, whereas
deposition processes create new land in other
places. In addition, the fact that the sea level is
rising locally and globally could add to these
erosion and deposition problems whilst also
removing land from use at the coastline.

4. What are Hard / Soft measures?
Hard
• Hard engineering
involves the building of
entirely artificial
structures using various
materials such as rock,
concrete and steel to
reduce or stop the impact
of coastal processes
• Ex:
– Groynes
– Sea Walls
Soft
• Soft engineering options
are often less expensive
than hard engineering
options. They are usually
more long-term
and sustainable, with less
impact on the
environment
• Ex:
– Beach Nourishment
– Due Regeneration

5. Recurved Sea Wall
• Massive, made of
rocks or concrete,
used to absorb
waves. Some types
can act as Baffles

6. Advantages
• Very effective
• Reasonably long
lifespan
• Traditional solution
• Can prevent coastal
flooding in some
areas
Disadvantages
• Very costly
• Visual pollution
• High maintenance
cost

7. Groynes
• Rock or wooden
types, hold beach
material threatened
by LSD erosion

8. Advantages
• Low capital costs
• Repaired pretty easily
Disadvantages
• Need regular
maintenance
• Cause scour downdrift
• Visual pollution

9. Rip Rap (rock armour)
• Very large rocks in
front of sea walls to
absorb waves

10. Advantages
• Very effective
• Prevents large-scale
undermining
Disadvantages
• Expensive
• May move in severe
weather

11. Off shore reefs
• Reduces power of
waves offshore

12. Advantages
• Can be built of waste
materials
• No visual pollution
Disadvantages
• Possible ecological
impacts
• May not work at large
scale

13. Toe armouring

14. Advantages
• Low maintenance costs
• 30-50 years effectiveness
Disadvantages
• High construction costs
• Disruption to ecology

15. Revetments
• Made of concrete or
wood.
• Reflects waves rather
than resist them

16. Advantages
• Cheaper than sea walls
• Traditional solution to
protect valuable
resources, densely
populated areas an high-
risk property
Disadvantages
• Costly
• Do not cope well with
very strong waves
• Visual pollution

17. Gabions
• Wire cages holding
smaller rocks
• Bank/cliff stabilisation

18. Advantages
• Cheaper than revetments
• The rocks absorb a
moderate amount of
wave energy
Disadvantages
• Relative small scale
solution
• Visual pollution

19. Cliff Stabilisation
• The drainage of
excess rainwater by
terracing, planting
and wiring to keep the
cliff in place

20. Advantages
• Cost effective
Disadvantages
• A moderate amount of
visual pollution
• Effects the ecology of the
cliff

21. Cliff drainage
• Removal of water in
order to prevent
landslides and
slumping

22. Advantages
• Cost effective
Disadvantages
• Drained cliffs can dry out
and lea to collapse
• Has effects on the
ecology
• Visual pollution

23. Beach nourishment
• Sand pumped or
transported to replace
losses by LSD

24. Advantages
• Looks like a ‘natural
looking’ process
Disadvantages
• Expensive
• Will erode soon
• Ecological effects

25. Natural (do nothing)
• Land no longer worth
protecting. Lets the
sea erode the land
with no intervention

26. Advantages
• Saves expenditures on
defence
• No impact on nature and
ecology
Disadvantages
• May allow problems to
get worse
• Loss of land