Coastal Systems and Landscapes - (The Holderness Coastline) Flashcards
How long is the Holderness coast and where does it stretch from?
It is 61km long and stretches from Flamborough head to spurn head.
True or false - The Holderness coast is eroding rapidly.
True.
What are most of the cliffs made up of?
Till (Boulder clay).
What type of waves is the Holderness coast exposed to from the North sea during storms?
Destructive waves.
What are the main four coastal processes operating at the Holderness coast?
Erosion.
Mass movement.
Transportation.
Deposition.
How does erosion operate at the Holderness coast?
The soft boulder clay is easily eroded by wave action.
In some places such as Great Cowden, the rate of erosion has been over 10m a year in recent years.
How does mass movement operate at the Holderness coast?
The boulder clay is prone to slumping when it is wet.
The water makes the clay heavier and acts as a lubricant between particles making it unstable.
How does transportation operate at the Holderness coast?
Prevailing winds from the northeast transport material southwards. These winds also create an ocean current, which transports material south by longshore drift. Rapid erosion means there is always plenty of sediment to be transported.
How does deposition operate at the Holderness coast?
This is where the ocean current meets the outflow of the Humber river, the flow becomes turbulent and sediment is deposited.
True or false - The Holderness does not need to be managed?
False. The Holderness needs to be managed.
How far has the Holderness coastline retreated in the last 2000 yeears?
4km.
How many villages have been lost due to the Holderness’ retreat?
Around 30.
What social, economic and environmental problems could the ongoing erosion cause in the Holderness coastline?
Loss of settlements and livelihoods. For example the village of Skipsea is at risk and 80,000 metres squared of good quality farm land is lost each year on the Holderness coast which has a huge effect on farmers livelihoods.
Loss of infrastructure. For example the gas terminal in Easington is only 25m from the cliff edge.
Loss of sites of specific scientific interest (SSSIs). For example the Lagoons near Easington provide habitats for birds.
How many km of the 61km coastline are currently covered by hard engineering?
11.4km.
What is Bridlington on the Holderness coast protected by?
A 4.7km long sea wall and timber groynes.
What protection is there at Hornsea to protect the village?
There is a concrete sea wall, timber groynes and riprap.
What was done at Mappleton in 1991 to protect the village and the B1242 coastal road?
They built two rock groynes and a 500m long revetment.
They cost £2 million.
What did a caravan park owner use at Skipsea
Gabions.
What defences are there at Withernsea?
Groynes and a sea wall. Some riprap was placed in front of the wall after it was damaged in severe storms in 1992.
What is the Easington gas terminal protected by?
A revetment.
What is the Eastern side of Spurn head protected by?
Groynes and riprap.
Are the existing schemes sustainable?
No.
What is the issue with the groynes at the Holderness coast?
They trap sediment increasing the width of the beaches. This protects the local area but increases erosion of the cliffs down drift as material from the beaches there is not replenished.
An example of this is the Mappleton scheme which has caused increased erosion of the cliffs south of Mappleton. Cowden farm, just south of Mappleton, is now at risk of falling into the sea.
What does the reduction in sediment produced at the Holderness coastline lead to?
The sediment produced from the erosion of the Holderness coastline is normally washed into the harbour estuary (where it helps to form tidal mudflats) and down the Lincolnshire coast. Reduction in this sediment increases the risk of flooding along the Humber Estuary and increases erosion along the Lincolnshire coast.
What has the protection of local areas leading to the the formation of bays between those areas done?
As bays develop the wave pressure on the headlines will increase and eventually the cost of maintaining the sea defences may become too high.
What did the SMP for Holderness recommend for the next 50 years as a management strategy?
‘Hold the line’ at some settlements such as Bridlington Withernsea, Hornsea, Mappleton and Easington Gas Terminal.
‘Do nothing’ along less populated stretches. However, this is unpopular with owners of land or property along the stretches where nothing is being done.
What is managed realignment and what are the pros and cons?
It was suggested and for example would be the relocating of caravan parks further inland and allowing the land they are on to erode. This would have been a more sustainable scheme as it would allow the coast to erode as normal without endangering business.
However, there are issues surrounding how much compensation businesses will get for relocating. Also, relocation is not always possible for example there may be no land for sale to relocate buildings to.
What did the Holderness Borough Council decide to do in 1995?
Stop trying to protect Spurn head from erosion and overwashing. ‘Do nothing’ became the new strategy. This saves money and allows the spit to function naturally, but overwashing may damage marsh environments behind the spit. A coastguard station on the spit may also be at risk.
What is the issue with the Easington Gas Terminal being protected by rock revetments?
The SMP recommends that these defences are maintained for as long as the gas terminal is operating.
However, the defences only span 1km in front of the gas terminal, meaning that the village of Easington with a population of about 700, is not protected. The defences may also increase erosion at legally-protected sites of special scientific interest (SSSIs) to the south.
