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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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Hornsea’s Coastal defences
Wooden groyne – notice the difference in sand heights. Wooden groynes and rock wall. Gabions. Concrete sea wall, protects the caravan park.
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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, would´ve 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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Mappleton’s 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
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. Withernsea, a large resort town, has now to spend millions to build toe revetment sea defences to protect the town. This is very costly. 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 Essential services at Spurn Point (Coastguard, Lifeboat) are now threatened as the spit is being starved of material. Wildlife to the rear of the Spit is losing a good migrating spot. These species are seen even less in the area. 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.
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