Just Cerfing Vol. 7, Issue 8, August 2016 Volume 5, Issue 3, March, 2014 | Page 32

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Soft Engineering vs. a Dynamic Approach in Coastal Dune Management
first is the ‘‘soft engineering’’ approach (hereafter referred to as ‘‘soft engineering’’). This strategy involves high control of local processes to fixate,
improve, or restore a predetermined dune shape and height for the purpose
of coastal protection. The second is known as ‘‘building with nature,’’ which
makes use of natural processes by stimulating them in such a way as to increase coastal safety or improve ecological quality.
Often a soft engineering approach has been used that involves placement
of sand fences between the sea and the foredune (defined as the first or most
seaward of the dunes) along with planting of Ammophila arenaria (marram
grass)(Arens, Jungerius, and Van der Meulen, 2001). From 1990, however, a
strategy called ‘‘dynamic coastal management’’ has been increasingly implemented (Arens and Wiersma, 1994; De Ruig and Hillen, 1997). In 2002
the Dutch Technical Advisory Committee for Flood Defenses defined dynamic coastal management as ‘‘managing the coast in such a way that natural processes, whether stimulated or not, can take place undisturbed as far
as possible, as long as the safety of the inland area is ensured’’ (TAW, 2002).
Dynamic coastal management is associated with the ‘‘building with nature’’
approach that is now taking root in The Netherlands (De Vriend and Van
Koningsveld, 2012).
An example of building with nature is the ‘‘sand engine’’ created along
the North Sea coast near The Hague. In this project, some 21 Mm3 of sand
has been added to the coastal system. The expectation is that natural processes will distribute the sand along the coastline in such a way as to increase safety against flooding in the long term (Van Dalfsen and Aarninkhof,
2009). Dutch management is thus moving away from engineering coastalprotection structures toward beach nourishment (Kabat et al., 2009) and
eco-engineering (Van Bohemen, 2004).
With less intensive foredune management, natural processes play a greater
role in flood protection, and foredunes gain a more natural appearance (De
Groot et al., 2012). Dynamic management of foredunes could also enhance
the conservation of Natura 2000 areas, which are a pillar of EU nature and
biodiversity policy. Among the EU-protected coastal habitat types are ‘‘embryonic shifting dunes’’ (habitat type 2110), ‘‘shifting dunes along the shore32

line with Ammophila arenaria’’ (white dunes, type 2120), and the priority
habitat type ‘‘fixed coastal dunes with herbaceous vegetation’’ (gray dunes,
type 2130) (De Ruig and Hillen, 1997; European Commission, 2007;
Ketner-Oostra and SÝkora, 2012).
Little is known about the effect of dynamic coastal dune management on
various dune functions, even though such management has already been
introduced on a large spatial scale. The current study, therefore, evaluates
the effect of dynamic coastal dune management on dune development (in
terms of, e.g., dune volume and shape) by comparing foredune development before and after the introduction of dynamic coastal dune management. Two adjacent dune sections are studied on the North Sea barrier
island of Ameland, The Netherlands. Dynamic coastal dune management
was intro-duced in these two sections in 1995 and 1999, respectively. To
determine the impact of dynamic coastal dune management, elevation
data was analyzed to discern changes in dune shape, height, and volume
for the period between 1980 and 2010. This time frame extends approximately 15 years before and after the introduction of dynamic coastal dune
management. Additionally, the effect of dynamic coastal dune management