Coastal management

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Coastal management
Coastal
management
Coastal
management
The four options
Coastal management
Coastal
management
Shoreline Management Plans (SMPs)
• SMPs were introduced by the government in
1995
• SMPs are an approach to coastal
management that involves all stake-holders
in making decisions about how coastal
erosion and coastal flood risk should be
managed
• They aim to balance economic, social and
environmental needs and pressures at the
coast
• Before SMPs, coasts were often managed in
a ‘piecemeal’ way, leading to problems and
conflicts
Groynes like these at Hornsea
can have an impact further down
the coast. SMPs aim to consider
these wider impacts before
defences are built.
Coastal management
Coastal
management
England and Wales SMPs
• There are 22 SMPs in England and
Wales
• They are numbered clockwise from
the northeast of England
• Each SMP manages an integrated
stretch of coast
• The SMP areas operate as a ‘coastal
unit’ with physical processes such as
longshore drift linking together
different places along the coast
• SMPs are managed by Coastal
Groups, made up of local councils
and the Environment Agency
SMPs along the east coast
of England
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Coastal
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SMP2: The Tyne to Flamborough Head
• SMP2 illustrates how the process works
• Seven council areas have to cooperate
over the management of SMP2
• Scarborough Borough Council is the
‘lead authority’
• The stretch of coast (red line on map)
includes large urban areas (Sunderland
and Redcar), small coastal communities
(Filey, Whitby) and important habitats
(the Tees estuary) as well as very
varied geology.
http://www.northeastsmp2.org.uk/finalSMP2.htm
Coastal management
Coastal
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Coastal management options
• DEFRA (the Department for Environment
Food and Rural Affairs) provides some
money for protection against coastal erosion
and flooding
• DEFRA money is provided through the
Environment Agency, which works with all
Coastal Groups on their SMPs
• Coastal Groups decide which of the four
strategies in the table will be used on a
particular part of their SMP
• Decisions about which strategy to use take
into account the views of all stakeholders
• This does not mean that all stakeholders will
be happy with the decision
Four coastal management strategies
No active intervention
No planned investment
in defending against
flooding or erosion,
whether or not an
artificial defence has
existed previously
(sometimes called ‘do
nothing’)
Hold the line
Build or maintain
artificial defences so
that the position of the
shoreline remains.
Sometimes the type of
defence may change to
achieve this result
Managed realignment
Allowing the shoreline
to move naturally, but
managing the process to
direct it in certain areas.
This is usually done in
low-lying areas, but may
occasionally apply to
cliffs
Advance the line
New defences are built
on the seaward side
Coastal management
Coastal
management
No active intervention
• This strategy ‘lets nature take its
course’.
• Erosion and coastal flooding occur
and cliff lines gradually retreat
• It is often used when coastal land is
of low value, for instance farm land,
or when only a few properties are
threatened with erosion
• It can also be used when rates of
erosion are rapid and the engineering
challenge of defending the coast is
too great
A collapsed road at Aldbrough on the
Holderness Coast. No coastal defences
have been, or will be, built here
Coastal management
Coastal
management
Managed realignment
• This option is a half-way house
between holding the line and doing
nothing
• Coast lines are allowed to erode/flood,
but gradually
• Some defences might be constructed in
the future to prevent continuous loss of
land or extensive flooding
• A famous example of managed
realignment is Spurn Head spit at the
southern tip of the Holderness Coast
• The plan is to allow the spit to erode
but move inland over time, intervening
to prevent it being breached by the sea
Map showing the possible future position
(red line) of Spurn Head spit as it erodes
west, towards the land. Defences could
be built to prevent a breach
Coastal management
Coastal
management
Hold the line
• This strategy is used when coasts
are deemed ‘high value’
• The value could be due to urban
development and industry
• In some cases rare ecosystems
might be protected in this way
• The line is held using engineering,
usually hard defences
• This strategy could be temporary in
some places, as rising sea levels
may make it impossibly expensive
to maintain in 50 or 100 years time
A large traditional (vertical face) sea wall
in Colombo, Sri Lanka
Coastal management
Coastal
management
Advance the line
• This strategy is very rare in the UK
• It involves building defences out to
sea – effectively creating new land
• It is very expensive
• It is also likely to be affected by
future sea-level rise, so defences
built today would need to be raised
and improved in the future
A view of a Palm Jumeirah in Dubai in
2008. This artificial island was open sea in
the Persian Gulf before construction
began in 2001
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