Case Studies

• Holderness Coast

  • Flamborough Head in the north, a chalk promontory that exhibits many typical landforms associated with coastal erosion.
  • Bridlington Bay to Spurn Head, an extensive zone of erosion and sediment transfer characterised by a very rapid rate of cliff retreat.
  • Spurn Head, a classic spit formed at the estuary of the River Humber.
• Holderness Coast prevailing wind is north-easterly, and most waves have a long fetch of 500-800km across the North Sea
• At the Holderness Coast, the sea floor is quite deep, meaning that waves encounter less friction and approach the coast faster.
• At the Holderness Coast, littoral drift transports about 3% of eroded sediment south to Spurn Head.
• Holderness Coast - In response to the rapid rate of erosion and the threat to settlement and infrastructure, parts of the coastline have been protected with hard-engineering structures such as sea walls, rock armour and groynes, however, these have had negative impacts further down the coast.
• Bridlington Bay to Spurn Head

  • Rates of erosion in excess of 1m per year
  • Erosion generates a massive amount of sediment that feeds the sediment cell
  • Sediment feeds Spurn Head which protects and borders the River Humber
• Flamborough Head

  • Made of chalk, a resistant, sedimentary rock
  • Cracks in chalk mean whole sections are displaces along faults, these are then exploited by erosion to destory the chalk.
  • Sea undercuts the cliff and leads to rockfalls
  • Waves approachign the coastline are refracting, means there is steep cliffs and a deposited beach
• Spurn Head

  • Material is derived from the Holderness Coast and transported south by littoral drift
  • Curved tip resulting from wave refraction
  • Formed over 8000 years ago, but is extremely thin so goes through cycles of being breached and rebuilt
  • In 1849, groynes and revetment were built to help stabilise the spit
• Holderness Management

  • SMP plan 'hold the line'
  • Bridlington protected by a 4.7km sea wall and timber groynes
  • Hornsea has a concrete sea wall, timber groynes and rip rap
  • Mappleton has two rock groynes and a 500m long revetment that cost £2 million
  • Withernsea has groynes and sea wall
• The Sundarbans region is 60% in Bangladesh and 40% within India
• Large area in the Sundarbans is mangrove forests
• Mangrove forests have long thick roots which absorb large amounts of carbon, whilst also providing natural coastal defences
• The Sundarbans is very flat and low-lying, if the mangrove forests all get destroyed then the area would be extremely vulnerable to flooding
• Opportunities in the Sundarbans

  • Flat, fertile land is ideal for crops
  • Rich ecosystem provides a lucrative fishing opportunity
  • Mangroves provide a natural flood defence and protect against coastal erosion
  • Opportunities for tourism
  • Proposed power plant
• Risks in the Sundarbans

  • A lack of freshwater as a lot of it is used for agriculture upstream
  • Flooding can lead to salinisation of soils
  • Growing population demands fuel and agriculture, so mangroves are being destroyed
  • Access is difficult with few roads
• Mitigation to challenges in the Sundarbans

  • Ramsar international wetlands protection
  • Integrated coastal zone management involced building 3500km of enbankments and replanting mangroves
  • Raised cyclone shelters and early warning systems
• Resillience in the Sundarbans

  • Self-help and bottom up community development
  • Support from NGOs in shcmes such as saline-resistant rice crops and training in sustainable methods of farming
  • Extension of electricity network
• Adaptation in the Sundarbans

  • Embankments
  • Saline resistant rice crops supported by NGOs
• In response to the risks in the Sundarbans, a lot of people in the fishing industry have now moved to prawn farming, but this is causing further issues of pollution and a reduction in fish numbers
• Groynes trap sediment, increasing the width of the beaches. However, this causes erosion further down the coast as sediment eroded is not replenished e.g. Cowden Farm, just south of Mappleton is at risk
• Sediment from the Holderness Coast usually washes into Humber Estuary and forms tidal mudflats, however a reduction in this increasesthe risk of flooding along the Humber Estuary and increases erosion on the Lincolnshire Coast.
• Protecting local areas is forming bays between them. As these develop, the pressure on local headlands will increase and eventually the cost of maintaining defences will become too high.
• Easington Gas Terminal is currently protected by rock revetments, and the SMP recommends these for as long as the terminal operates. However these span 1km in front of the terminal, but the village of Easington with a population of 700 people is not protected.