The Holderness Coastline of England suffers from the highest rates of coastal erosion in Europe due to its soft, easily eroded geology and exposure to strong winds and waves from the North Sea. Several villages have been lost to coastal erosion over the centuries. While some areas implement hard coastal defenses like seawalls and rock armor to combat erosion, these strategies are costly to maintain and can worsen erosion elsewhere down the coast. Integrated coastal zone management is now sought to balance protection of infrastructure with the natural shoreline processes.
2. The Holderness Coast is a 61 km long stretch of low glacial
drift cliffs ranging from 3m to 35m in height, which stretches
from Flamborough Head in the north to Spurn Head in the
south.
The coastline sweeps in a smooth S-shape which is only
broken where sea defences have reduced erosion at the
protected point and increased it southwards.
The Holderness coastline suffers the highest rate of coastal
erosion in Europe and mainly consists of soft glacial drift cliffs
which have been cut back up to 200m in the last century.
3. GEOLOGY: About a million years ago the Yorkshire coastline was a line of chalk cliffs almost 32
km west of where it now is. During the Ice Age (18,000 years ago) deposits of glacial till (soft boulder
clay) were built up against these cliffs to form the new coastline. The boulder clay consists of about
72% mud, 27% sand and 1% boulders and large pebbles.
CAUSES OF EROSION:
The whole coast in gradually
trying to reshape its self into a
shape that lies at a right angle
to the predominant wave direction
-The coast faces the dominant wind and wave direction and the long the long fetch from the Arctic Ocean
create powerful waves. Waves during normally occurring storm events can reach up to 4 m and are of
great importance as erosion mainly occurs during storms and tidal surges.
-The chalk headland of Flamborough prevents transport of materials from the north, therefore little beach
material is transported southward to the beaches, as a result of this, beaches are narrow and unable to
stop wave erosion
- The rock type is easily eroded through corrasion and is prone to slumping when wet.
4. FLAMBOROUGH
HEAD:
Flamborough head is characterised by high steep chalk
cliffs containing numerous caves, arches, stacks and slumps
SPURN HEAD:
Clear evidence of the long shore drift is found in the
development of the spit at the southern end of the Holderness
coast. The spit is built up of sand and shingle and is extending
in the Humber estuary at a rate of 10cm per year
5. SOCIAL IMPACTS OF EROSION: ECONOMIC IMPACTS OF EROSION:
- Around 30 villages have been lost since Roman - Numbers of visitors to areas along of this coastline
times, meaning homes and businesses have been has dropped.
lost.
- Some settlements unable to maintain a viable
- Many of the settlements rely heavily on tourism, as population to warrant shops.
facilities close down the settlements are unable to
maintain a good population. - Money has to be spent on coastal management
and protection
- Properties under threat of erosion lose their value
leaving owners with negative equity. - The Gas Terminal in Easington, which supplies
25% of Britain's gas, is at risk.
- 80000m2 of farmland is lost each year, this has a
huge effect on farmers livelihoods
ENVIRONMENTAL IMPACTS OF EROSION:
- Wildlife behind Spurn Point is losing diversity as
the environment cannot support many species
due to the lack of sediment
- Some SSSIs (Sites Of Special Scientific Interest)
are threatened by erosion
6. Today the coastline is approximately 4km inland from where it was during the
Roman times and there are many lost villages that have been lost to the sea since
then.
There is a debate about whether humans should intervene and attempt to defend
the coastline as its geology, the north sea waves and the shape of the coast line
makes erosion almost inevitable.
7. SO WHAT IS BEING
DONE TO COMBAT
COSTAL EROSION ?
-Since the late 19th century coastal protection has been used to enforce a ‘hold the line’
policy at the coastal towns of the Holderness coast.
-In between the coastal towns large areas are eroding while no measures are taken.
-Nowadays the local and regional authorities are trying to set up integrated coastal zone
management programmes for the whole Holderness coastline and the Humber estuary.
8. BRIDLINGTON:
Bridlington is predominantly an urban development offering tourism related
establishments and recreational water sports. It is an operational fishing
community and nationally important for sea birds.
To prevent erosion here, there are coastal defences such as, a 4.7km long
sea wall to protect the sea front and a wide beach, which is encouraged by
wooden groynes.
9. SKIP SEA
Skipsea is located on approximately 10miles(16km) South of
Bridlington.
Coastal Management here is limited to a small concrete wall
to protect the residential area.
10. HORNSEA:
Hornsea has 2.9km stretch of shoreline fronting the town. This high-density
urban development is dependent on tourism and recreation as well as a small
fishing industry. Due to the towns infrastructure, it was one of the places
chosen for protection against erosion.
There are original, 100 year old defences which have held up well, however
more recently, new defences were installed. Presently there is a wave return
wall, they also have groynes and riprap. They also use beach nourishment to
protect the coastline
Just south of Hornsea, gabions help protect the caravan park
11. MAPPLETON:
Mappleton, a small village that consists of approximately 50 properties, it has the B1242 road running
through it that links the towns along the Holderness coastline.
This road would have been lost to erosion had no protection been put in place but it was decided that
the total cost for coastal protection in the small village was less that the cost of building a new road.
As a result of this, rock armour was placed along the base of the cliff, two rock groynes were built and
a 500m long revetment was built.
12. WITHERNSEA:
Withernsea is a thriving holiday resort comprising 2.3km of
developed frontage. It is recognized as a popular tourist and
recreational site. Caravan parks, a golf course, residential and
commercial developments add to the local economy. Surrounding
land is put over to agriculture or open land.
There are groynes on Withernsea beach to ensure wide and
relatively steep beaches. The beach material is made up of sand and
shingle. The majority of the Withernsea frontage is provided coastal
protection in the form of concrete seawalls and riprap.
13. PROBLEMS WITH HARD ENGINEERING
MANAGEMENT STRATAGIES HERE:
- They can be costly
- Have to be maintained (e.g. sea walls + create strong backwash which erodes under the defence
and other types of defences can be damaged in storms)
- Encourage erosion further down the coast as they starve down drift beaches of sand- thinner
beaches don’t protect the coast as effectively. E.g. Coastal protection at Mappleton has caused
increased erosion of the cliffs south of Mappleton.
- Sea walls make it more difficult to access the beach so may discourage tourism
- In areas where nothing has been done to protect the coast, ad hoc, private sea defences have
been put in place- private defences are not of the same engineering standard so can pose
health and safety issues, they can undermine defences elsewhere.
-The protection of local areas is leading to the formation of bays between areas, however as they
bays develop wave pressure on the headlands will increase, and the cost and difficulty of
maintaining these may become impossible to sustain. This pressure will be due partly to the
concentration of wave energy on any projecting headland but also because the sea bed will
continue to erode offshore and the resulting deeper water will allow more wave attack at the
shore.