Make your objectives
Achievable - Are the objectives
you set, achievable and attainable?
Realistic – Can you realistically
achieve the objectives with the resources you have?
Time – When do you want
to achieve the set objectives? |
Once an erosion problem has been specified (step
1) and quantified in terms of one or more
indicators (step
2), and once a benchmarking procedure has
been established (step
3), a decision must be made on the most applicable
intervention method.
1. Objectives
Designing an intervention
procedure, it is important to memorize the context of the problem
and the objectives that must be achieved (step
1, step
2, step
3 ). All this should be reflected in the nature of the design,
it’s geographical extend and temporal dimension (life cycle).
2. Technically feasible and ecologically optimal
Understanding the dynamic nature of the coastal margin is a key
factor in managing coastal erosion. EUROSION
recognises the sustainable development of coastal zones and the
conservation of dynamic habitats, especially on the remaining
undeveloped coast, as important long term goals for European coastal
zones. This requires a respect for, and in many cases restoration
of, the natural functioning of the coastal system and hence its
natural resilience to erosion. Key
concepts like resilience, coastal sediment cells, favourable
sediment status and strategic sediment reservoirs play an important
role.
A technically feasible and ecologically optimal intervention
scheme, according to EUROSION
should be found in restoration of the sediment balance and providing
space for coastal processes.
Buffer zone
Allowing space for natural dynamics may be accomplished by delimiting
and maintaining a buffer zone. The landward boundary of such zone,
where building restrictions and prohibitions are applied, generally
is defined as a set back line. A set
back line basically is a trade off between coastal development
and prevention of an unacceptable risk due to coastal erosion.
An overview of the defintion of set back lines in Europe is provided
by CONSCIENCE report D12.
Sediment nourishments
For restoration of the sediment balance and maintainance of a
buffer zone, an obvious option is sediment nourishment. Coastal
erosion including sea level rise effects can be mitigated by shoreface,
beach and/or dune nourishments with sediments of comparable size
or with slightly coarser sediments.
Pilot sites Holland,
Coast
Brava and Hel
Peninsula represent examples of sand nourishments, pilot site
Pevensey
is an example of gravel nourishment. An overview of potential
interventions and practical experiences is presented by CONSCIENCE
report 13a.
Hard structures
In cases where local availability of sediments is lacking, or
in urban areas where space for natural dynamics of coastal processes,
is limited, hard structures may be applied to combat erosion.
Coastal structures such as groynes, detached breakwaters and artificial
reefs are built to significantly reduce coastal beach erosion
and to maintain a minimum beach width for recreation or to protect
beach fills.
Pilot site Coast
Brava and Romania
represent examples of the effects and effectiveness of hard structures.
An overview and evaluation of different potential interventions
and practical experiences is presented by CONSCIENCE
report 13a.
3. Financially feasible
It is difficult to make generalised cost estimates of potential
interventions. Cost largely depend on local conditions, such
as the design of the measure, the availability and type of material
used, local prices for labour and material etc. A cost-benefit
assessment may shed light in this matter.
Some rough cost estimates based on practical experience, are presented
by CONSCIENCE
report 13a.
4. Who is accountable ?
Considering “Accountable coastal erosion management”,
EUROSION
indicates a.o. the importance of (-) clear responsibilities at
various levels of administration and (-) an appropriate budget
for both investments and maintenance as well as for a financial
mechanism to locally accommodate erosion or its impacts.
As illustrated for example by the various CONSCIENCE pilot
sites and by CONSCIENCE report D8,
accountability differs largely across Europe. A clear analysis
of these aspects at a particular site, is necessary to attain
an implementable strategy.
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