Cumbria

• Background:

  • High uplands (such as the Cumbrian Fells) which causes orographic rainfall
• Background:

  • Seathwaite, in Cumbria, averages 2 months of flooding / year. Suseptable to heavy rain.
• Meterlogical causes:

  • Warm westerly winds coupled with high relief (orographic rainfall)
• Meterlogical causes:

  • Deep Atlantic low pressure system brought heavy prolongued rainfall through a mechanism called 'warm conveyor'
• Meterlogical causes:

  • Moist air stayed over Cumbria for up to 48 hours
• Human activity's affects: changing land use

  
  

  • Many towns built on floodplains + impermeable land (such as Cockermouth)
  • Runoff from farms (where animals overgraze) go to flood plains
  • Less trees, more bogs
  • Lower lead time, higher peak discharge
• Human activity's affects: mismanagement of rivers

  • Hard management built off 'Flood return periods' which is based on the likelihood of a flood and its magnitude. CC has changed this
  • When rivers which have been dredged (fast moving water) meet rivers with no dredging results in flooding upstream.
• Social cost:

  • 3,000 homes flooded in 2005
  • Over 5,200 homes flooding in 2015
• Social cost:

  • Local services such as hospitals and 40 schools closed.
• Social cost:

  • Electricity substation flooded resulting in lack of electricity
• Gusts of up to 81mph (2015)
• 2015 Storm Desmond
• Economic damage:

  • £500m cost of damages in 2015
• Economic damage:

  • In UK, insurance claims due to flooding was over $8b
• Economic damage:

  • Farmer's sheep died
• Economic damage:

  • Falling house prices - Cockermouth (2009 Oct) = £217,000. (2009 Nov) = £213,000 (average house price). Flood happened around then.
• Economic damage:

  • Falling tourism due to risk of flooding.
• Environmental costs:

  • River banks eroded which increases future flood risk (reduced capacity for river + less vegetation on bank)
• Environmental costs:

  • River were choked with debris and contaminated by sewage and pollutants.
• Environmental costs:

  • Saturated ground causes landslides
• Hedgerow removal has reduced natural vegetation interceptors + increasing population meaning less green space.
• London:

  • 5% of London is car parks (impermeable) - land use change.