holderness coast

• Coastal erosion at the Holderness coast?

  The Holderness coast has been reshaped by energy released onto the shoreline by the sea in the form of wave and tidal forces.

  Currently the entire cliff and coastal frontage from Flamborough to Spurn Point is being surveyed every six months, and a detailed picture of cliff erosion, sand movements and beach conditions is being developed. Maintenance schedules are then adjusted to ensure that all the structures are functioning correctly and safely
• Holderness coastal protection?

  Coastal protection is in place at specific settlements in the coastal zone – Bridlington, Hornsea, Mappleton and Withernsea – as well as at the gas terminal at Easington and the site of a major land drain at Barmston.

  There are also several private defences, associated with the large caravan parks at Skipsea and Ulrome; these have temporary planning consent. Away from these areas the coast is undefended.
• Mappleton protection?


  The current defences at Mappleton were constructed in 1991 after an economic case was made.

  Cliff erosion looked set to claim the village and the main road that links many of the coastal villages.

  The coast protection works were put in to defend 450 metres of cliff line using 61,500 tonnes of rock armour to build two groynes and a sloping revetment
• Holderness coast conflict?

  The impact of the physical coastal processes on residents and businesses in Holderness has been considerable and has created conflict.

  Many local residents and businesses feel that coastal protection should be maintained and extended to avoid loss of roads, farms, houses or caravan sites.

  Others argue that additional protection works will further upset natural processes, leading to loss of sediment supply in other areas of the coast.

  This would damage homes, businesses and the ESAs of the Humber mudflats and the Lincolnshire coast
• Spurn point?

  For the past 6,000 years, sand moving south along the Holderness cliff line has settled to form a spit across the mouth of the Humber estuary.

  Erosion continuing along the coast has periodically removed part of the spit but eventually the deposition process builds a new one.

  The destruction and rebirth of the spit follows a 250-year cycle.

  However, the natural cycle ended in the mid 1800s when coastal protection works on the spit started.
• What is then likely outcome of spurn point?

  By 1961, following increasing maintenance costs, the decision was taken to abandon the defences, allowing natural processes to continue again.

  The likely outcome is that erosion will wash away most of the spit, leaving an island at its tip, and it will gradually re-form having moved further west.

  The coastline south of Spurn Point will then no longer be protected and so will also come under attack by the sea
• What types of beaches are at the Holderness coast?

  narrow and unable to stop wave erosion

  during the winter they have only a thin layer of sand covering the underlying clay, and in summer the beaches build up enough for recreational purposes
• What is the geology of the Holderness coast?

  • The Holderness coast is predominately boulder clay
  • This leads to particular sub-aerial processes
• What are the sub-aerial processes that occur at the Holderness coast?

  wetting and drying

  freeze-thaw

  slumping
• Wetting and drying?

  • At high tide the particles expand when covered with water, at low tide they dry out and contract
  • Repeated wetting and drying causes the clay to crumble
• freeze-thaw?

  • During the winter months, water enters the fractures in the boulder clay
  • At night this water freezes and expands - due to Arctic maritime air masses
  • Repeated expansion and contraction, causes the cliff to be weakened
• slumping?

  • The Holderness coast regularly experiences wet weather
  • Weathering leaves cracks in the boulder clay
  • Water enters these cracks, causing the clay to become heavier, and lubricated (slippery)
  • This leads to a large area of land moving downslope in one piece - known as rotational slip
• • Along the Holderness coast, weathering and mass movement work together, causing the fastest rate of coastal erosion in Europe
  • The rate of erosion is approximately 1.8 metres a year
• What is the method of erosion at the Holderness coast?

  a cyclic 4 stage process

  1. the soft boulder clay cliffs become saturated with rain water and lose their strength
  2. the cliff is too steep and fails either as a block of material or as a slurry side (mass movement)
  3. cliff failure reduces the angle and prevents further erosion
  4. large waves from the North East remove the debris in longshore drift to the South and the cliff oversteepens, rain falls and the cycle begins again
• Holderness coast is located in the East-Coast of England

  erosion rate 2m per year

  29 villages lost since roman time

  glacial till deposited 18,000 years ago in the last Ice Age : boulder clay which erodes rapidly - crumbles easily doesn't require lots of wave action to be eroded
• Erosion at Mappleton?

  east coast of yorkshire

  own groynes to portect village, used rock armour, rip rap and sea walls

  where there is no protection (farmland) , erodes rapidly , waves hit side of cliffs thus is retreating several metres per year
• Mappleton?

  in 1991 a scheme costing £2.1 million, supported by EU funding, was put in place including 2 rock groynes and rip rap

  blocks of granite were imported from Norway for the sea defences

  cliffs between the 2 groynes have been stabilised through landscaping and vegetation cover

  substantial beach has been retained

  groynes have been attributed to causing increased erosion at Great Cowden, 3km down the coast
• What is Rip Rap?

  Rock or concrete used to protect shorelines from erosion.
• Skipsea?

  series of Gabon cages built by the local landowner

  groynes are locally effective, acceptable visually and development of low lying land has now been possible

  Gabions protect only small area, erosion occurring either side at Skipsea
• What are the causes of the coastal erosion at the Holderness coast?

  the bedrock is made up of till (boulder clay)- lack of resistance, erodes rapidly

  waves have a long fetch over the north sea

  small beaches offer little protection as waves are destructive

  sea level rise is a further threat

  this material was deposited by glaciers around 18,000 years ago
• The Holderness Coastline is in the North of England and runs between the Humber estuary in the south and a headland at Flamborough head.

  It has the reputation as the worst place in Europe for coastal erosion, and in a stormy year waves from the North Sea can remove up to 10m of coastline.

  It's one of the fastest eroding coastlines in Europe as a result of it's geology.
• The coastline starts with headlands, stacks and stumps at Flamborough, and culminates with Spurn Head spit that runs ........ of Humber Estuary.
• • the North Sea and the Mediterranean sea often generate huge waves during storms
  • waves move within the sea, but cannot disperse their energy
• • the sea floor is relatively deep along the Holderness coast, so waves reach the cliffs without first being weakened by friction with shallow beaches
  • thus the waves have more energy and little wave action is required anyway due to the lack of resistance to erosion boulder clay has
• What problems have the groynes in Mappleton caused?

  has protected the coast in Mappleton, however further down the coast at Great Cowden erosion has increased (Terminal Groyne syndrome) as sediment is trapped on one side of the groyne, thus starving Great Cowden of sediment from longshore drift

  this has led to farms being destroyed by the erosion and the loss of 100 chalets at the Golden Sands Holiday Park.
• What are the environmental impacts?

  by protecting certain areas along the coast it has worsened erosion in other places (TGS)

  essential services will soon have to be moved, due to defences further along the coast, Spurn point is not receiving enough sediment

  wildlife behind Spurn Point is losing diversity as the environment cannot support many species due to the lack of sediment

  the headland at Flamborough has formed into classic examples of stacks, arches, stumps and caves
• What are social and economic impacts?

  farms alongside the sea are devaluing and losing profits yearly as land falls into the sea

  properties along the coast lose their value, leaving owners in negative equity

  many of the settlements rely heavily on tourism and if they are undefended their trade would diminish as facilities close down

  there would be little or no new investment to sustain local communities

  the loss of jobs and few jobs mean that young people move away from the settlements along the coast
• What do environmental stakeholders want?

  RSPB and English nature want to see continuation of sediment movement to Spurn point spit, as this depositional feature provides a habitat with its salt marshes and mud flats
• What does the local government do?

  has joint responsibility with the central government

  continued funding cuts
• Under lying the Holderness Coast is bedrock made up of Cretaceous Chalk. However, in most place this is covered by glacial till deposited over 18,000 years ago. It is this soft boulder clay that is being rapidly eroded.
• Sedimentary rocks with very weak cementation, e.g. boulder clay

   is unstratified and structureless and contains gravel of various sizes, shapes, and compositions distributed at random in a fine-grained matrix
• Because the clay is weak and less resistant rock, it erodes rapidly. In fact, the Holderness Coast is one of Europe's fastest eroding coastlines. The average annual rate of erosion is around 2 metres per year - in a stormy year destructive waves from the North Sea can remove between 7 and 10m of coastline.
• . Erosion along fault lines has created features such as cliffs, arches and stacks which are vulnerable to sub-aerial processes such as hydraulic action