Zusammenfassung der Ressource
Chapter 5: Coastal change and Conflict (Part 2)
- People + coastal retreat
- Sue Earle, farmer - Hornsea, East Yorks
- 1994 - watched her home of 25 years be demolished - lost battle against north sea waves
- Farm 39 years earlier 150m away form sea
- erosion has accelerated when sea defences were built at Mappleton
- Norcliffe family - Barmston, north of Hornsea
- 2004 - home was 1.5m away from edge
- no defences against waves
- The Humber estuary Coastal shorline management plan - 'do nothing' - potential economic damage to caravan parks +
isolated farms - not enough to justify defences
- a rollback policy for caravan parks but not homes
- Holderness, East Yorkshire
- 60km long stretch of low cliffs (20-30m)
- cliff line retreating - 2m a year - fastest in Europe
- erosion takes place in storms + tidal surges (6m lost in a storm in 1967)
- over 4 km lost since Roman times
- what's the problem?
- cliffs made of soft glacial clay
- coast very exposed - waves have long fetch over north sea
- sea level rise - more attack
- destructive waves
- Beaches are narrow due to longshore drift - little protection
- conflicting views
- The eldery - lived here whole lives - too old to move
- Farmers - lost valuble land - no compensation
- Caravan park owners - whole business threatened -
cannot afford to buy more land
- Politicians - not economically justifiable as the
edges are not densely populated
- Chief engineer - an inevitable natural
process - impossible to protectwhole coast
- Shoreline Management plans
- 1. Do nothing
- 2. Advance existing defence line by more hard engineering
- 3. Hold existing defence line by maintaining/ improving standard of protection
- 4. Retreat existing defence line (strategic realighnment)
- strategies are expensive to put in place
- so a cost-benefit analysis is done -
- + how sustainable
- Costs
- loss of farmland
- loss of caravan parks + holiday chalets
- cost of sea defences
- loss of houses
- loss of roads
- Benefits
- no loss of homes or businesses
- erosion of cliff stops
- no loss of land or farms
- coastline is stabilised
- Coastal Management
- Hard engineering
- Sea wall
- + protects cliffs and buildings
- - Expensive
- Groynes
- + prevents sea removing sand
- - exposes other areas of coastline
- Rip rap
- + rocks absorb wave energy
- - expensive
- Off-shore reef
- + waves break on reef and lose power
- - interfere with boats and fishing
- Soft engineering
- Beach replenishment
- + sand reduces wave energy and maintains tourism
- - expensive
- Managed retreat
- + people and activities avoid erosion by moving inland
- - expensive and disruptive
- Cliff regrading
- + mass movement less likely
- - foot of cliff still needs protection from waves
- Integrated coastal zone mangement
- the system of dividing the UK coastline into zones that can be managed holistically
- reduces damage to environment
- Case study of traditional coastal engineering structures
- Durlston Bay, Dorset
- erosion mainly occured at one particular point -
major weakness in rock
- safeguard houses + apartments on cliff top
- Regrading cliff - extended forward at base - slope longer - therefore less steep
- Installing drainage - remove excess water - slope not as heavy or lubricated after rain
- Rip rap - large granite boulders (8 tonnes each) at base - resist wave attack
- Swanage Bay, Dorset
- erosion occured on a considerable length not
just one point
- safeguard houses and hoteld (e.g. Grand Hotel) gardens
- Sea wall - built in 1920s - provided promenade and a barrier to wave attack
- Cliff regrading - series of steps in cliff - lower slope angles
- Groynes - timber groynes in 1930s - 18 recently replaced- reduced long shore drift - beach for protection
- Beach replenishment - 90,000m3 from studland bay
- cost of groynes and replenishment - £2 million