somerset levels case study

state why Somerset Levels was prone to flooding

• below sea level

• overrun with artificial drainage

• lack of river dredging

• vastly high tidal range

• increased extreme weather - more rainfall and winds

explain why Somerset Levels being below sea level made the area prone to flooding

• Somerset Levels spans 250 square miles

• majority of this area is below sea level

• this made the land vulnerable to tidal and land-based flooding

• the maximum attitude in this area is only 8m above sea level

explain why Somerset Levels being overrun with artificial drainage made the area prone to flooding

• thousands of years ago, the area was covered by sea

• however today, it’s a landscape of rivers and wetlands

• which are artificially drained, irrigated and modified to allow productive farming

explain why Somerset Levels lacking river dredging made the area prone to flooding

• the River Tone and the River Parrett run through Somerset Levels

• neither river has been dredged properly in 20 years

• this left farmland and homes without proper defence from floods

• as the non-dredged sediment washes downstream

• the accumulation of sediment downstream raises the river bed and reduces the river capacity

state the definition of dredging

• act of removing silt and other material

• from the bottom of bodies of water

• which increases river depth and capacity

explain why Somerset Levels having a vastly high tidal range made the area prone to flooding

the Severn Estuary (Bristol Channel) has the second highest tidal range in the world

explain why Somerset Levels experiencing increased extreme weather made the area prone to flooding

• early 2014 - UK was hit by the worst storms for 20 years

• a succession of storms developed over the Atlantic, tropical and polar maritime air masses also blew in

• this caused high wind speeds due to the pressure differences between the two air masses

• this resulted in the Somerset Levels receiving 200-250% of its usual winter rainfall

state the human causes of the 2014 flooding in the Somerset Levels

• building has developed on the floodplain, much of which is below sea level

• thousands of years ago, the are was covered by sea, but today it’s a landscape of rivers and wetlands which are artificially drained, irrigated and modified to allow productive farming

• farming practices have changed and become more intensive which means land is less able to retain water

• the Rivers Tone and Parrett which run through the Levels had not been dredged properly for 20 years

  • the River Parrett in particular was blocked an in desperate need of dredging

  • the dredging process used to happen every 5 years (costing £4 million)

state the physical causes of the 2014 flooding in the Somerset Levels

• prolonged rain, hurricane-forced wind speeds and tidal surges caused widespread flooding

• the storms were caused by a powerful jet stream driving low pressure systems and their storms across the Atlantic Ocean

• from mid-December 2013 to mid-February 2014 there were 12 major storms

• the Severn Estuary has the second highest tidal range in the world and when it is high tide floodwater doesn’t travel out to sea as quickly

• the majority of this area is below sea level, making the land vulnerable to tidal and land-based flooding - maximum altitude of the Levels is only 8m above sea level

• at 193% of average rainfall, it was the wettest January in England since 1910

state the social consequences of the Somerset Levels flood, 2014

• people had to move - impacted transport to work/school

• hard to access homes due to flooding

• the mental health of local residents was harmed largely by the flood

• 165 homes were affected by the flood

state the economic consequences of the Somerset Levels flood, 2014

• people not be able to get insurance coverage for flooding in Somerset Levels

  • insurance premiums had also increased vastly

• total cost of damage to properties is approx. £16 million

• house values depreciated in the flooded areas

  • houses were being sold at 2/3 of their price

• houses were flooded and damaged - this caused people to have to pay to move

state the environmental consequences of the Somerset Levels flood, 2014

• local fauna had no food to eat and were drowning in the flood waters

  • this led to loss of biodiversity in Somerset

state the social short term impacts of the Somerset Level flood, 2014

• 81 road closures

  • this meant residents in Muchelney (village) could only leave the island by boat, which left every 2 hours

• hundreds of people had to evacuate

• people were reluctant to leave their homes dur to fears of looting

• trains disrupted Bristol line between Bridgwater and Taunton

• many residents had to seek temporary accommodation elsewhere

• high opportunity for thieves

  • 900L of fuel was stolen from pumping stations in Westonzoyland

state the economic short term impacts of the Somerset Level flood, 2014

• tourism industry lost £200 million

• 50% of businesses impacted by flooding

• 86% of businesses impacted by road closures

• costs of necessary goods started to rise

  • emergency fuel pumps used to reduce water levels during flooding cost £200,000 per week

• local businesses reported over £1 million losses

• cost the county’s tourism industry £200 million

state the environmental short term impacts of the Somerset Level flood, 2014

• fluctuations in wildlife numbers, breeding patterns and locations for some species

• maximum area of land on the Levels covered by winter floods 65 km²

state the social long term impacts of the Somerset Level flood, 2014

• lack of trust in government from local communities due to mis-handling of floods pre and post the event

• loss of livelihoods from permanent damage to farmland

• emotional devastation and heartbreak from losing homes

• more than 600 homes were flooded

state the economic long term impacts of the Somerset Level flood, 2014

• insurance prices increased - went up five fold after flooding and will were set to triple as a result

• government had to invest in long-term flood defence engineering to protect areas at risk

  • dredging, tidal barrage and extra permanent pumping sites cost £100 million

  • 8km dredging of the Rivers Parrett and Tone cost £6 million

state the environmental long term impacts of the Somerset Level flood, 2014

• soil was damaged after being under millions of tonnes of water for months

  • it took 2 years for soil in the Levels to recover

• 6880 Ha of farm land was flooded

state the local stakeholders in the Somerset Levels flooding, 2014

• FLAG (residents)

• Somerset County Council

state the regional stakeholder in the Somerset Levels flooding, 2014

Environment Agency (EA)

state the national stakeholders in the Somerset Levels flooding, 2014

• Royal Marines

• government (including David Cameron)

state the local management strategies of the Somerset Levels flooding, 2014

• Thorney village put in a £180,000 earth embankment built to help protect 10 houses

• section of A372, between Aller and Othery (which had been flooded), reopened after 11 weeks of flood prevention work

  • this work included installing a temporary bridge

  • the finishing of this prevention work marked the first phase of flood protection at Beer Wall

  • 28 miles of flood-affected roads were repaired and resurfaced

• FLAG formed to help support local residents affected by the floods and pressure the government to do more

state the regional management strategies of the Somerset Levels flooding, 2014

• there was a Somerset County Council plan to fund a new ‘Somerset Rivers Authority’

  • this was initially funded by the national government (£2 million was paid), but future funds rely on enhanced maintenance of river channels and flood banks in order to help reduce the risk of flooding

• two councils - Somerset County and Sedgemoor District - declared a ‘major incident’ in a bid to mobilise extra support

  • they raised £1.5 million towards repairs

• a list of 10 trigger points on the Somerset Levels have been drawn up which allow additional pumps to be switched on to remove water from a given area

state the national management strategies of the Somerset Levels flooding, 2014

• a ‘Somerset Levels and Moors Action Plan’ was formed

  • it was a 20 year, £100 million plan commissioned by Environment Secretary Owen Paterson

  • David Cameron said ‘money is no object’ - national government announced the funding of £10.5 million to the project

  • the Department of Transport is backing it with £10 million

• the Somerset Rivers Authority is working with Sedgemoor District Council and the EA on plans to create a £100 million tidal barrier across the River Parrett by 2027

  • it will protect ~13,000 homes and 1,500 businesses from coastal changes

• Royal Marines were deployed to help villagers cut off by the floodwater

• the EA installed 62 pumps, working 24/7 to remove 1.5 million tonnes of water

state embankments definition

• raised banks along the river

• increase the capacity of the river by making it deeper

• increased capacity increases the volume of water able to flow

• this prevents the water from bursting the river’s banks and flooding

state sluices definition

• artificial channel for carrying water

• contains an opening at one end to control the flow of water

• sluice gates can reduce water flow downstream by preventing water from flowing any further

• this decreases water volume downstream, preventing the water from bursting the river banks

• this prevents flooding downstream, where there may be settlements