travels very quickly down from the uplands but then slows down and pools in the
Somerset Levels and Moors. The high-level embanked channels overflow and
floodwater is stored in the Moors before it can reach the Estuary. In addition, the very
shallow gradient on the Somerset Levels and Moors means that the area drains water
away very slowly and relies on a complex network of pumped drainage channels.
Tide locking is a particular feature of the Somerset Levels and Moors; the lower
reaches of the rivers Tone and Parrett are tidal for some 30 km (18.6 miles) from the
Severn Estuary. The capacity of these channels can be significantly reduced by high
tidal conditions; in particular the Parrett as it has no tidal sluice or control structure.
Widespread flooding of the lowland moors happens regularly from the perched
main rivers which run through them. The moors are protected by raised defences as are
many of the small villages and communities. During the 2013/2014 fluvial floods, flood
defences across the area protected over 200 km
2 of land and over 3500 properties.
However, large areas of land were still flooded for many weeks and these included 172
properties. Strategic infrastructure which included main roads and the rail network were
affected badly and some small communities were cut off for many weeks.
Climate change increases both the risk of flooding and drought in Somerset. UK
droughts are projected to be more severe and affect larger areas of the country over
the next 100 years. Example studies include a publication in the journal Water
Resources Management (Rahiz and New 2013) and a study by scientists from the
European Commission’s Joint Research Centre and Kessel University (2014).
Climate change will also increase the potential for stronger rainfall events. The
implications for flood risk, however, will vary widely from location to location
depending on local climatic changes that are at present difficult to predict with
confidence. Climate change may also result in changes to large-scale atmospheric
circulation patterns like jet streams, which are harder for climate simulations to
predict. Recent results with state-of-the-art climate models have raised the possibility that climate change may affect the jet stream more than scientists previously
expected, making floods in the UK more likely. However, the uncertainty in these
projections remains large. Flash flooding could also become more frequent as
extreme rainfall events are consistently predicted to become more severe.
5.2.2 Regulatory and Governance Context of English Water
Management
In 2008 the UK government ratified the Climate Change Act. One aspect of this
piece of legislation ensures relevant public bodies put plans in place to adapt to
climate change. This has involved a range of activities specifically focused on
adapting to climate change such as the National Adaptation Programme, and the
UK Climate Change Risk Assessment (e.g. HM Government 2013; Wade et al.
2013). For example, the UK government now has ‘Adaptation Reporting Power’
requiring a range of stakeholders and companies to provide detailed reports on the
86
A.L. Browne et al.
Somerset Levels and Moors. The high-level embanked channels overflow and
floodwater is stored in the Moors before it can reach the Estuary. In addition, the very
shallow gradient on the Somerset Levels and Moors means that the area drains water
away very slowly and relies on a complex network of pumped drainage channels.
Tide locking is a particular feature of the Somerset Levels and Moors; the lower
reaches of the rivers Tone and Parrett are tidal for some 30 km (18.6 miles) from the
Severn Estuary. The capacity of these channels can be significantly reduced by high
tidal conditions; in particular the Parrett as it has no tidal sluice or control structure.
Widespread flooding of the lowland moors happens regularly from the perched
main rivers which run through them. The moors are protected by raised defences as are
many of the small villages and communities. During the 2013/2014 fluvial floods, flood
defences across the area protected over 200 km
2 of land and over 3500 properties.
However, large areas of land were still flooded for many weeks and these included 172
properties. Strategic infrastructure which included main roads and the rail network were
affected badly and some small communities were cut off for many weeks.
Climate change increases both the risk of flooding and drought in Somerset. UK
droughts are projected to be more severe and affect larger areas of the country over
the next 100 years. Example studies include a publication in the journal Water
Resources Management (Rahiz and New 2013) and a study by scientists from the
European Commission’s Joint Research Centre and Kessel University (2014).
Climate change will also increase the potential for stronger rainfall events. The
implications for flood risk, however, will vary widely from location to location
depending on local climatic changes that are at present difficult to predict with
confidence. Climate change may also result in changes to large-scale atmospheric
circulation patterns like jet streams, which are harder for climate simulations to
predict. Recent results with state-of-the-art climate models have raised the possibility that climate change may affect the jet stream more than scientists previously
expected, making floods in the UK more likely. However, the uncertainty in these
projections remains large. Flash flooding could also become more frequent as
extreme rainfall events are consistently predicted to become more severe.
5.2.2 Regulatory and Governance Context of English Water
Management
In 2008 the UK government ratified the Climate Change Act. One aspect of this
piece of legislation ensures relevant public bodies put plans in place to adapt to
climate change. This has involved a range of activities specifically focused on
adapting to climate change such as the National Adaptation Programme, and the
UK Climate Change Risk Assessment (e.g. HM Government 2013; Wade et al.
2013). For example, the UK government now has ‘Adaptation Reporting Power’
requiring a range of stakeholders and companies to provide detailed reports on the
86
A.L. Browne et al.