CGP Coastal Environment Case Study

• Holderness Coastline

  Eroding rapidly
• Erosion of the Holderness Coastline

  • Caused by wave action
  • Exacerbated by boulder clay being heavier and acting as a lubricant between particles
• Transportation

  1. Wind from the northeast transports sediment

  2. Ocean current transports sediment southwards by longshore drift

  3. Rapid erosion means there is always plenty of sediment to be transported
• Deposition


  Where the ocean current meets the outflow of the Humber, the flow becomes turbulent and sediment is deposited
• Coastal landscapes around Holderness

  • Steep chalk cliffs, wave-cut platforms and sandy beaches in the north
  • Less-steep boulder-clay cliffs and depositional features around Spurn Head in the south
• Coastal landforms

  • Headlands and wave-cut platforms
  • Flamborough Head features like stacks, caves and arches
  • Slumping cliffs
  • Beaches
  • Sand dunes
  • Spit (Spurn Head)
• The Holderness coastline has retreated by around 4 km over the past 2000 years, and around 30 villages have been lost
• Ongoing erosion could cause

  • Loss of settlements and livelihoods
  • Loss of infrastructure
  • Loss of Sites of Special Scientific Interest (SSSIs)
• 11.4 km of the 61 km Holderness coastline is currently protected by hard engineering
• Hard engineering schemes

  • Bridlington sea wall and groynes
  • Concrete sea wall, timber groynes and riprap at Hornsea
  • Rock groynes and revetment at Mappleton
  • Gabions used by a landowner in Skipsea
  • Groynes and sea wall at Withernsea
  • Revetment protecting Easington Gas Terminal
  • Groynes and riprap protecting eastern side of Spurn Head
• Existing hard engineering schemes are not sustainable
• Groynes trap sediment, increasing the width of beaches


  This protects the local area but increases erosion of the cliffs down-drift as the material eroded from the beaches isn't replenished
• Reduction in sediment from Holderness coastline erosion

  Increases the risk of flooding along the Humber Estuary and increases erosion along the Lincolnshire coast
• Protection of local areas

  Leads to the formation of bays between those areas, increasing wave pressure on headlands and making the cost of maintaining sea defences too high
• The Shoreline Management Plan for Holderness recommends 'holding the line' at some settlements and 'doing nothing' along less-populated stretches
• Managed realignment has been suggested, but there are issues around compensation for businesses and the availability of land to relocate to
• In 1995, Holderness Borough Council decided to stop trying to protect Spurn Head from erosion and overwashing, allowing the spit to function naturally
• Easington Gas Terminal is currently protected by rock revetments, but the defences only span about 1 km in front of the gas terminal, leaving the village of Easington unprotected, and may increase erosion at nearby protected sites
• The Holderness coastline


  • Boulder clay cliffs
  • Distinctive shape
  • Tiered cliffs due to slumps that have not yet been eroded
• Locations with slumps


  • Around Atwick Sands
• Spurn Head


  • Spit with a recurved end across the mouth of the Humber Estuary
  • Estuarine mudflats and saltmarshes have formed on the landward side
• The Holderness coastline has retreated by around 4 km over the past 2000 years
• Around 30 villages have been lost due to erosion
• Ongoing erosion could cause


  • Loss of settlements and livelihoods
  • Loss of infrastructure
  • Loss of Sites of Special Scientific Interest (SSSIs)
• The gas terminal at Easington is only 25 m from the cliff edge
• The sediment produced from the erosion of the Holderness coastline is normally washed into the Humber Estuary 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
• The protection of local areas is leading to the formation of bays between those areas
• As bays develop the wave pressure on headlands will increase and eventually the cost of maintaining the sea defences may become too high
• These problems make the existing schemes unsustainable
• Coastal management recommendations for Holderness in the next 50 years


  • Holding the line at some settlements
  • Doing nothing along less-populated stretches
• Holding the line and doing nothing is unpopular with owners of land or property along the stretches where nothing is being done
• Managed realignment


  Relocating caravan parks further inland and allowing the land they are on to erode
• Managed realignment would be more sustainable as it would allow the coast to erode as normal without endangering businesses
• There are issues surrounding how much compensation businesses will get for relocating, and relocation isn't always possible
• In 1995, Holderness Borough Council decided to stop trying to protect Spurn Head from erosion and overwashing - do nothing became the new strategy
• Doing nothing at Spurn Head saves money and allows the spit to function naturally, but overwashing may damage marsh environments behind the spit
• Easington Gas Terminal is currently protected by rock revetments, and the SMP recommends that these defences are maintained for as long as the gas terminal is operating
• The defences only span about 1 km in front of the gas terminal, meaning that the village of Easington isn't protected
• The defences may also increase erosion at legally-protected Sites of Special Scientific Interest (SSSIs) to the south