The document discusses coastal erosion issues in Happisburgh, England. It notes that over 250m of land was lost between 1600-1850, and 125m was lost between 1992-2007 at a rate of around 8m/year. The cliffs are comprised of glacial sands and clays that are easily eroded by the sea and saturated by rainwater. Coastal defenses could worsen the situation by disrupting sediment flows, while rising seas and stronger storms from climate change also increase erosion risks. The rapid erosion is negatively impacting the local community and environment through lost homes and infrastructure as well as valuable farmland.

1. COASTAL
MANAGEMENT
ISSUES

2. Coastal erosion can lead to cliff collapse. This creates
challenges for people and the environment.
A case study of an area of recent or threatened cliff collapse
to show:
• Rates of erosion and change in the area
• Why the area is susceptible to coastal processes and cliff collapse
• How human impacts may worsen the situation
• The impact of rapid cliff recession on people and the
environment.

3. What we’re going to do...
Review why some areas are more susceptible than others
Look at areas of rapid erosion in Eastern England
Fieldwork to Highcliffe to investigate management issues

4. Why are some areas
more susceptible to
erosion than others?

6. Coastal erosion on the Norfolk coast
(Happisburgh)

7. Location

8. http://www.happisburgh.org.uk/
http://www.bgs.ac.uk/landslides/happisburgh.html

9. Rates of erosion and change in the
area

11. Photo taken 01/03/96

13. 01/01/86
01/01/03

15. 01/01/86
01/01/03

16. Summary:
Historic records indicate that over 250 m of land were lost between
1600 and 1850.
1992-2007 – 125m lost: rate of erosion c. 8m/year (BGS website)
Some areas eroding faster than others – affected by the degree of
protection afforded by coastal defences

17. Why is this area so susceptible to
erosion?

18. The cliffs at Happisburgh are between 6-10m high and are comprised of
a series of glacial sands and clays deposited during and at the end of the
last Ice Age (2mya – 10,000 ya).
These are easily eroded by the sea and …
.. rainwater easily percolates through the sand and saturates the clays,
making them more mobile and more likely to slump.
Although there is some sand in the cliff material, most of it is clay …
…which is carried away in suspension.
The small amount of sand isn’t enough to form a wide beach …
… so there’s little to protect the base of the cliff from further erosion.

19. How the cliffs erode

20. Sediment is transported
northwards and southwards away
from this area of Norfolk – so
there is no through movement of
sediment to replace that which is
removed
This coast also is exposed to
storms in the North Sea that can
raise tide heights by up to 2m
Happisburgh

21. Photo taken 01/03/96

22. Draw an annotated field sketch of this photo. Identify the coastal features, the
type of mass movement shown and suggest why is it happening.

23. How might human impacts may
worsen the situation?

24. Human activity
• Coastal defences along the coast … how/why might these have an
impact?
• Rising sea levels and increased
frequency of storms?

25. The impact of rapid cliff recession
on people and the environment
Living with coastal erosion at Happisburgh (1)
Living with coastal erosion at Happisburgh (2)

26. Social impacts:
• 27 houses lost to sea since 1986 – c. 60 people directly affected;
• 18 listed buildings will be lost including the only privately operated
working lighthouse in the country;
• A thriving community – volunteers run the lifeboat and coastguard
team, and they have well-organised campaign to save the village

27. Economic impacts:
• Happisburgh has a shop & post office, pub and school – will these
survive?
• Tourism: caravan park, tea rooms and a number of guest houses –
will people still come?
• Without protection, coastal erosion is a certainty, not a risk:
• Inability to insure properties
• house as an investment – can they be sold?

28. Political issues:
• Timber defences built in 1959 but started failing in the '80s
• Construction of a rock groyne was started at the south end of Beach
Road in 2001…
• …but it was halted because there were 2 objections to the work
(despite 325 letters of support).
• By December 2002 so much erosion had happened that the scheme
was scrapped – the erosion had led to properties being lost to the
sea and so the financial benefits of building the defences were now
less than their cost

29. Environmental impacts:
• Loss of valuable farm land

30. Coastal
management
solutions

31. Different strategies can be used to reduce the threat of
erosion/flooding in coastal areas.
Management strategies include:
• Hard engineering – including sea walls, groynes, rock armour.
• Soft engineering – including beach nourishment, dune
regeneration and marsh creation.
• Managed retreat – coastal realignment and monitoring
A case study of a coastal management scheme to assess the
costs and benefits of the adopted strategy.

32. What can be done to
protect rapidly eroding
coastlines?

33. Hard engineering
 Uses artificial structures to control or deflect the forces of
nature
Soft engineering
 Makes use of natural processes to reduce wave energy,
usually without artificial structures.

34. Whilst we look at some of the different
methods, consider the following:
Which methods are less visually intrusive and therefore less
likely to deter visitors?
Which methods might be more effective?
Which are likely to be the most expensive?
Which do you think offer the most sustainable approach?

35. Hard
Engineering

36. Sea Walls

37. Blackpool

39. Groynes

40. Swanage - old

41. Swanage - new

42. Rock Armour
(aka rip rap)

44. Morecambe

49. Soft
Engineering

50. Soft engineering methods…
…try to fit in with and work with the natural processes
…do not involve large artificial structures
…are often more ‘low-key’
…have low maintenance costs (economically &
environmentally
…are usually more sustainable

51. Beach
Replenishment

53. Beach replenishment
What is it?
Costs approximately £3000/m
Advantages: Disadvantages
Relatively cheap & easy to maintain Can be easily damaged by storms
Blends in with existing beach
(eventually)
Unless structures are also built to retain
the beach it will need regular
maintenance/replenishment
Increased beach width may/will attract
more tourists
Can be unsightly whilst material is re-worked
by the sea.

54. Dune
Regeneration
We’ll do this at the end when we
look at dune systems

55. Managed Retreat
(aka managed re-alignment)
Marsh Creation

56. Northern coast of the Blackwater estuary, Essex

58. Porlock, North Somerset Class Clips: 3243

59. Managed retreat/coastal realignment
What is it?
Costs depend on value of land – arable is £5k-£10k per ha
Advantages: Disadvantages
Cheap compared to cost of building and
maintaining defences to protect low
value land
Farmers will need to be compensated
Creates much needed and valuable
habitat for wildlife
Land can only be used for a limited
range of land uses, e.g. animal rearing
Animals can graze land at low tide

60. Monitoring

61. 1. Which methods are less visually intrusive and therefore
less likely to deter visitors?
2. Which do you think are the more sustainable methods:
hard or soft engineering? Explain your choice.
3. Why do you think some schemes include both hard and
soft engineering, for instance, beach replenishment and
groynes?

62. Which method or combination of methods is chosen (if
any) depends on:
• the suitability of the method for that part of the coast, and
• the outcome of a Cost-Benefit Analysis:

63. Costs Benefits
What will it cost to complete?
What are the advantages that
justify the cost?
How much will it cost to
maintain?
For how long will the benefits
last?
Who will be badly affected by
it?
Who will gain from it?
Which areas will be badly
affected by it?
How large an area will gain
from it?
How bad will any
environmental damage be?
How big an improvement to
the environment will there be?

64. Some of the people likely to have views about coastal protection
are:
A Birdwatchers C Holiday camp owners
B Londoners D Council treasurers in resorts
E Farmers with land on cliff-tops
F Economic advisors to the government
G People with coastal retirement homes
H Families who take summer holidays by the sea
a) Draw a line like the one below and put the letters A-H along
the line to show the likely feelings of the people above:
Do nothing Total protection
b) Explain your choice of position on the line for someone
towards each end and someone towards the middle.