CASE STUDIES

• Sustainable coastal management strategies

  • Managing natural resources for long-term productivity
  • Managing flood/erosion risk or relocating to safe areas
  • Creating alternative livelihoods before existing ones are lost
  • Adapting to rising sea levels by relocating, building methods, water supplies
  • Educating communities on why change is needed and how to adapt
  • Factoring in coastal change and unexpected trends
• Holderness Coast

  • Fastest rate of coastal erosion in Europe, retreating by up to 10m per year
  • Mainly cliffs of soft glacial sands, gravels and boulder clay
  • Very exposed to destructive waves from the northeast
  • Much of the eroded material is carried out to sea
• Holderness - Since Roman times, the Holderness coastline has receded by 5km, with many villages and much farmland lost
• Portland Bill > Selsey Bill - Sediment cell

  • Portland Bill to Selsey Bill on the south coast of England
• Portland Bill to Selsey Bill sediment cell

  • Has a strong south-westerly prevailing wind
  • Erosive processes dominate a large part of the coast on the western side of the cell
• Portland Bill > Selsey Bill - Erosion and accretion in the sediment cell

  1. Eroded material from the Isle of Purbeck moves into the west of Poole Bay and accumulates around the entrance to Poole Harbour

  2. At Poole harbour a spit has formed on both the southern and northern edge.
• Portland Bill - Spit formation

  1. Spits have formed on the southern and northern edges of Poole Harbour

  2. Further spits are located at Hengistbury Head and near Hurst Castle
• Portland Bill > Selsey Bill - Minor currents emerging from the estuary at Southampton

  Move into the Solent and prevent Hurst Spit from joining up to the Isle of Wight
• Portland Bill - Northeast side of the Isle of Wight

  • Has calmer waters which protect the inlets around Portsmouth and allow accretion to take place there
• Portland Bill to Selsey Bill

  3. Minor currents from estuary at Southampton move into the solent + prevent Hurst spit from joining to IOW.

  4. The northeast side of IOW has calmer waters, these protect inlets around Portsmouth and allow accretion to take place.
• Glamorgan Heritage Coast


  • 14-mile-long stretch of high-energy coastline in South Wales
• Glamorgan Heritage coast


  • Bristol Channel funnels large, destructive waves onto the coast from the south-west
• Glamorgan Heritage Coasts - Destructive waves


  Create a highly-eroded discordant coastline prone to cliff falls
• Glamorgan Heritage Coasts - Reactivity


  Some rocks contain chemicals that make them more susceptible to erosion (e.g. carbonates)
• The Glamorgan Heritage Coast is characterised by high vertical cliffs made of sedimentary rocks (Carboniferous limestone, sandstone, shale and mudstone)
• Glamorgan Heritage Coast - There are headlands at Witches Point and Nash Point and sandy bays near Dunraven and Merthyr Mawr
• Glamorgan Heritage Coast - There are large areas of wave-cut platforms made from limestone, especially around Nash Point
• The Nile Delta, in northern Egypt, is home to 50% of the country's population
• Nile Delta - The 22 000 km² area contains the final stretch of the River Nile before it empties into the Mediterranean Sea
• The Nile Delta is considered a densely populated coastal area
• Nile Delta - Saltwater intrusion


  Saltwater infiltrating the soil from below
• Nile Delta - Rising sea level in the Mediterranean

  High amounts of erosion
• Nile Delta - Rising sea level


  Low-lying areas at the front of the delta becoming more saline
• Nile Delta - Saltwater intrusion


  Floods leaving salt deposits on the land
• Nile Delta - Saltwater intrusion : This makes it increasingly difficult to farm the delta as the fertility of land is decreasing
• Nile Delta - Freshwater lakes and lagoons are now too salty to use for irrigation
• Nile Delta - Some fish species are unable to survive in the water in the delta, which threatens the future of the fishing industry
• Nile Delta - The transportation of sediment along the Nile has reduced significantly since the building of the Aswan Dam in 1970
• Nile Delta - Before then, 9.5 million tonnes of sediment washed down the Nile and onto the delta every year
• Nile Delta - Now, fluvial sediment coming down the River Nile is not replacing the eroded material from the coast of the delta
• Nile Delta - The Aswan Dam holds back over 98% of the Nile's sediment in Lake Nassar
• Nile Delta - Rising sea level and low levels of sediment deposition from the Nile


  The Nile Delta is retreating-up to 140 m a year in some places
• Flood risk in Bangladesh


  • Three major rivers (the Brahmaputra, the Ganges and the Meghna) all flow through Bangladesh and enter the Indian Ocean through the Bay of Bengal
  • Around 50% of the country is at an elevation of 10 m above sea level or less
  • Approximately 20 million people live in areas less than 1 m above sea level
  • A lot of this low-lying land is on the coast where there is a large delta
  • Tropical cyclones regularly cause storm surges on the coast
  • Monsoon rains increase the amount of floodwater
• Bangladesh: Bay of Bengal islands


  • Hundreds of small islands
  • Unconsolidated material makes up the majority of the islands
  • Material comes from the three main rivers as sediment deposits, which makes the islands highly unstable and susceptible to flooding
  • As sea level rises, more of these islands are at risk
  • Scientists estimate that 8000 km² of land in Bangladesh will disappear if sea level rises 0.3 m from its current level
• Bangladesh: Farmers clearing mangrove forest on the delta and draining it to increase farmland


  • The delta used to be a site of net deposition but some parts are now a site of net erosion
  • This, in combination with its low elevation, makes it more vulnerable to flooding from the rising sea level
• Coastal management - Happisburgh 


  Happisburgh, England - developed country
• Happisburgh Coastline

  • Vulnerable
• Happisburgh is a small village in North Norfolk with around 1400 residents and 600 properties
• Happisburgh - Sea defences built in the 1950s have been destroyed due to weathering and mass movement
• Happisburgh - Managed retreat policy adopted in 1996

  1. Predicted 200 m of coastline would be lost by 2105

  2. Large number of properties, a caravan park, 45 hectares of agricultural land and a number of heritage buildings at risk of destruction as the cliff continued to erode