Holderness protection objectives and management strategies
Since the late 19th century coastal protections have 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 also
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. In the East Riding Integrated Coastal Zone
Management Plan the policy options (do nothing of hold the line)
are given along the Holderness coast, these are shown in Table 3.
The policy option managed realignment is being considered at
Holderness for the future (see Strategy).
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Hornsea Location A 2.9km stretch of shoreline fronting the town
of Hornsea. A high density urban development containing residential
and various tourist related properties, Hornsea's local economy is
dependent on tourism and recreation as well as incorporating a
small fishing industry. Geology Hornsea lies upon unconsolidated
till. This material was deposited by glaciers during the last ice
age 18,000 years ago. Coastal Features The groynes on Hornsea beach
ensure wide and relatively steep beaches. The beach material is
made up of sand and shingle.
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Hornsea Coastal Management The position of the coastline at
Hornsea has been artificially fixed since existing coastal defences
were erected in the early 1900s. Hard defences in the form of a
concrete seawall and timber groynes afford protection and an on
going refurbishment programme ensure this has continued. More
recently a stone gabion has been erected to the south of Hornsea.
This helps protect the caravan park. Beach material is being
transported south along the Holderness Coast by longshore drift. In
Hornsea sand has accumulated where protection exists. This is
because the groynes provide a barrier to sediment transportation.
This has reduced erosion within the section but increased rates are
evident further south.
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Hornseas Coastal defences Wooden groynes and rock wall.
Concrete sea wall, protects the caravan park. Wooden groyne notice
the difference in sand heights. Gabions.
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Mappleton Location Situated approximately 3km south of Hornsea
lies the village of Mappleton. Supporting approximately 50
properties, the village has been subject to intense erosion at a
rate of 2.0m per year, resulting in the access road being only 50m
from the cliff edge at its closest point. Geology Mappleton lies
upon unconsolidated till. This material was deposited by glaciers
during the last ice age 18,000 years ago. Coastal Features The two
rock groynes at Mappleton have helped develop wide and steep sandy
beaches.
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Why protect Mappleton ? In 1990, Mappleton was under threat
from losing 30 houses along the coast of Holderness. Its main road,
the busy B1482, wouldve disappeared into the sea and would be very
expensive to rebuild. So, a coastal management scheme was set up.
Blocks of granite were imported from Norway so two groynes could be
built. This would trap the beach sediment that is being eroded away
due to longshore drift. This would then absorb some of the energy
from the waves so less energy would be directed on the cliff's
side. This would reduce erosion.
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Mappleton Coastal Management In 1991 two rock groynes and a
rock revetment were built, as a consequence a substantial beach
accumulated between the groynes halting erosion. However, further
south the rate of erosion has increased significantly. This is
because material which is being carried south is not being replaced
(it is trapped within the groynes). Therefore there is no beach to
protect the cliffs. Even during a neap tide ( a tide which is 30%
less than the average tidal range) the sea reaches the base of the
soft cliffs and erosion occurs.
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Mappletons coastal defences The rock groynes prevent longshore
drift and encourage deposition of sediment. This creates a beach
and a natural barrier that prevents waves from breaking directly on
the cliff base. This therefore prevents erosion.
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No beach, no defence ! The process of longshore drift can no
longer transport material along the coastline to be deposited at
the base of the cliffs. All the sand has gathered at Mappleton,
this leaves the glacial till cliffs exposed to the sea. The rates
of erosion just south of Mappleton have in places been as much as
10 metres per year. People have lost their homes, farmland and
livelihoods.
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Spurn Point Spurn Point is a narrow sandy coastal spit
aproximately five kilometers long. It is located on the south-
eastern tip of the Holderness plain which forms the northern banks
of the Humber estuary. Spurn Point is a feature of coastal
deposition and reguires a constant supply of sediment from the
process of longshore drift.
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Spurn Point The strategic position of the sand spit, guarding
the entrance to a major waterway lead to its use as a position for
shipping beacons and lighthouses. Historical accounts of
settlements and lighthouses, particularly accounts of their
destruction and the break up of the spit have enabled us to
discover that over the last 1000 years there have been five 'Spurn
points'. Each spit has grown until it has become unstable, been
destroyed and then rebuilt slightly to the west of the former one,
the cycles lasting approximately 250 years. The current spit is
nearing the end of the cycle, and despite considerable coastal
defences the neck is in continual danger of being breached.
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Why protect Spurn Point ? Spurn Point protects many wildlife
habitats and ecosystems which have developed behind the spit. Spurn
Point itself has essential services such as the Lifeguard station.
Many wooden groynes and other coastal defences have been built to
protect and preserve the spit. However if sediment is prevented
from reaching Spurn Point the consequences could be immense.
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Why protect Spurn Point ? Spurn Point protects many wildlife
habitats and ecosystems which have developed behind the spit. Spurn
Point itself has essential services such as the Lifeguard station.
Many wooden groynes and other coastal defences have been built to
protect and preserve the spit. However if sediment is prevented
from reaching Spurn Point the consequences could be immense.
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Implications of protecting the Holderness Coastline 1.Saved the
village and road. Mappleton row has a beach and a growing tourist
trade. But - local downstream farmers are losing land at an even
quicker rate. The farmers profits are being threatened.
2.Withernsea, a large resort town, has now to spend millions to
build toe revetment sea defences to protect the town. This is very
costly. 3.Industry at Easington is being threatened with the gas
terminals coming too close to the sea. This is not only dangerous
but could force the gas terminal to close with the loss of 1000s of
jobs 4.Essential services at Spurn Point (Coastguard, Lifeboat) are
now threatened as the spit is being starved of material. 5.Wildlife
to the rear of the Spit is losing a good migrating spot. These
species are seen even less in the area. 6.Long term effects on
King' s Lynn and Amsterdam have yet to be analysed but they may
need to take on extra sea defences
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Summary The Holderness Coastline is shaped by erosion,
transportation and deposition. These work together to create a
variety of coastal features (caves, stacks, beaches, spits).
Erosional processes (corrasion, corrosion, attrition and hydraulic
pressure) produce some interesting features especially at
Flamborough Head. They also cause many problems further down the
coast where the geology is less resistant (Mappleton, Hornsea).
Coastal defences include wooden groynes, rock gabions, concrete sea
walls and the beach. Developing these in certain areas however has
important implications further along the coast. However careful
planning is needed to ensure that the whole coast is managed in the
most sustainable manner.