Boscastle flood

• What significant flood event occurred in Cornwall in 2004?

  Boss Castle floods
• Why are the Boss Castle floods important for UK case studies?

  They illustrate extreme weather events
• How often is a one in fifty year flood expected to occur?

  Once every fifty years
• What geographical features characterize the area around Boss Castle?

  Steep valleys and rivers
• What was the total rainfall during the Boss Castle floods?

  200 millimeters
• How quickly did the 200 millimeters of rain fall?

  In just 24 hours
• What contributed to the rapid surface runoff during the floods?

  Steep valley sides and tarmac surfaces
• How many rivers feed into the river Valency at Boss Castle?

  Three rivers
• What role did the tarmac car park play in the flooding?

  It increased runoff speed
• How did trees contribute to the flooding at Boss Castle?

  They created a dam effect
• What was the outcome for the bridge during the floods?

  The bridge collapsed
• What was the largest airlift operation since World War II related to?

  Rescuing people from rooftops
• How many people were rescued during the Boss Castle floods?

  Many people were rescued
• What psychological impact did the floods have on survivors?

  Post-traumatic stress disorder
• What economic impact did the floods have on Boss Castle?

  Insurance premiums increased
• What was the total cost of the damage caused by the floods?

  15 million pounds
• What management strategy involved removing trees near the river?

  Deforestation
• What was the purpose of the new flood warning system created by the Met Office?

  To inform residents of potential floods
• How much wider was the river made to accommodate flooding?

  Three meters wider
• By how much was the river deepened to increase capacity?

  0.75 meters deeper
• What type of surface was used for the new car park to reduce runoff?

  Gravel surface
• How did the floating cars contribute to water pollution during the floods?

  They released toxins into the river
• What was the impact of planting trees on existing farmland?

  Farmers lost land for crops
• What was the purpose of creating drainage channels during the floods?

  To divert water away from the main river
• What are the key management strategies implemented after the Boss Castle floods?

  • Deforestation of trees near the river
  • Afforestation further down the river
  • Creation of a flood warning system
  • Widening and deepening the river
  • Closing the old car park and creating a new one
  • Establishing drainage channels
• What are the impacts of the Boss Castle floods on the community?

  • No fatalities reported
  • Psychological effects like PTSD
  • Damage to homes and buildings
  • Increased insurance premiums
  • Economic loss totaling 15 million pounds
• How did the Boss Castle floods change the flood risk assessment for the area?

  • Changed from a 1 in 50 year event
  • Now prepared for a 1 in 500 year flood event