Case study: Jurassic Coast

• Coastline features

  Stump - langstone rock

  Beach - dawlish beach

  Spit - dawlish warren spit

  Sand dune - dawlish warren sand dunes (sand littered on top of obstacles)

  Cliffs - red cliffs at dawlish
• Evaluate a sea wall

  Hard engineering - concrete barrier: long lasting, people enjoy walking along them, allow Longshore drift BUT are expensive, beach access is difficult, ugly, damage habitats
• Evaluate groynes

  Hard engineering - wooden fences or walls: reduce the rate at which long shore drift carries material, long lasting BUT can increase rates of erosion
• Evaluate rip rap armour

  Hard engineering - rocks placed at base of cliff to absorb energy, long lasting BUT let water through, allow some erosion, ugly, easily moved by waves
• Evaluate gabions

  Hard engineering - wire cages filled with boulders: allows build up on beaches BUT short term, easily destroyed by waves, cages rust easily
• Evaluate revetment

  Hard engineering - sloping concrete or wooden defences absorb wave energy: durable, short term, need replacing, don't give total protection
• Evaluate off shore water break

  Hard engineering - rocks built up parallel to the coast: effective at reducing wave energy, don't spoil the beach BUT expensive, tricky to maintain
• Evaluate beach replenishment

  Soft engineering - extra sand is added to replace the loss by Longshore drift: waves lose energy by the time they reach cliffs, protects coast, increased tourism BUT needs to be replaced regularly
• What is a blue flag beach?

  One that's clean, safe, low pollution, accessible and managed to allow this
• What is the multiplier affect

  A chain of consequences where investment leads to wealth and a spiral of improvement
• Dawlish warren storm consequences

  Cause risk to life

  Destroyed some of the railway

  Forced people out of their homes

  No power

  Local business had no customers

  Travel stopped
• Dawlish warren storm management

  Temporary Sea wall

  25000 tonnes of eroded cliff was removed

  Railway was cleared and repaired
• How was Dawlish warren protected in the past

  A rating system the higher the score the better the defence
• Dawlish warrens spit

  Built up as a result of sand deposition at the estuaries mouth

  Due to Longshore drift - north easterly

  Spit couldn't grow further due to river outlet moving material