Theme 8 - New Sustainable Coastal Engineering Techniques
Welcome to the main page of Theme 8.
Visitors of the Theme 8 part of the Coastal Wiki should keep in mind (for the time being) that the work is still fully in progress. That means that they (often) will find contributions which are clearly in a very draft shape.
This main page briefly introduces the scope and articles of Theme 8 and provides contact information.
In Overview of Theme 8 a more extended overview of, and introduction to Theme 8 is given.
See also the alphabetic overview of Theme 8 articles.
Within the basic framework of ENCORA the main emphasis of Theme 8 is on coastal engineering techniques related to morphological developments of coasts (e.g. erosion, accretion) and to shore protection (e.g. approach, methods, tools). That means that many quite interesting parts of coastal engineering (e.g. breakwater design, offshore platforms, offshore windmills, wave energy converters) are not dealt with.
A well-developped system of Integrated Coastal Zone Management (ICZM) is especially important if many different (often: conflicting) interests play a role in the coastal zone. It is felt that along a sandy coast in general more interests must be taken into account than along e.g. a muddy coast (compare for instance recreation and housing topics). This means that in Theme 8 hardly any attention will be paid to muddy coasts.
The functional design aspects of e.g. a proper coastal protection scheme are the main items in the Theme 8 contributions. (E.g. position and crest height of a detached submerged breakwater). Although very important in practice, structural design aspects (e.g. how to determine the mass of an armour layer of a submerged breakwater?) are not dealt with.
In preparing the various contributions it is assumed that the Wiki reader is somewhat familiar with general notions related to Coastal Engineering like tides, tidal currents, wave characteristics (e.g. wave height H and wave period T), orbital motion, wave driven currents and e.g. sediment properties.
Topic of articles
Theme 8 covers the topics of coast erosion, coastal protection, the effects of coastal protection measures, and Coastal Zone Management. See also the alphabetic overview of all articles within the scope of theme 8.
The topic coastal erosion is described in a general article about types and background of coastal erosion. Other articles are:
- Dune erosion: erosion of the mainland because of a severe storm (surge), a so-called episodic event.
- Structural erosion (or background erosion): long-term, gradual, year after year erosion processes. This type of erosion might be due to (still) merely natural processes, or might in fact be considered as the response of the coastal system to human interferences in that system in the (far) past. It is expected that structural erosion will be enhanced by global sea level rise. The need for more and better protection schemes will consequently increase in future. See also typical examples of structural erosion
The topic coastal protection is described in a general article about protection against coastal erosion. Other articles are:
- Protection by hard shoreline protection structures like:
- Protection by soft shoreline protection solutions like:
'Soft' solutions are sometimes supplemented by “invisible” structures, like light revetments built-in into artificial dunes. These hidden revetments are a kind of “second line of defence” during extreme storms, when the beach and dune is washed out.
Other alternative protection measures are: Beach drainage
Effects of shore protection solutions on the coastal morphology
In many cases the application of hard shoreline protection structures did not meet the expectations, because the hard shoreline protection techniques affect the coastal morphology in a negative way.
This has resulted in the continuous development of other and often innovative coastal protection techniques. Sometimes the application of soft shoreline protection solutions lead to better results. However, these 'soft' measures affect the coastal morphology as well.
Coastal zone management
A sustainable shore protection solution has to meet various requirements. Not only hydraulic aspects must be taken into account. Also the use of the coastal zone in a broader sense must be taken into account. This is also referred to as Coastal Zone Management.
Among other things, environmental issues play an important role in shore protection. A swash zone, being a part of the coastal region, constitutes a natural environment inhabited by many living organisms. Their importance in coastal ecosystem consists in the active bio-filtration of suspended particles, processing of organic matter and the primary production. The entire surf zone (including the swash zone, which during storm surges spreads landwards to the dune toe) acts similarly to a biocatalyst filter in a modern waste water treatment plant. Therefore, artificial beaches and dunes are preferred as environmentally “friendly”.
In overview of Theme 8 a more extended overview of the content of Theme 8 is given. By way of that article the reader is more or less 'guided' through the relevant articles of Theme 8.
Contributions and contact
The basic idea of a Wiki is that 'everybody' can contribute to the content. If you would like to make contributions to theme 8, we invite you to do so. Informing the coordinator of Theme 8 Jan van de Graaff from the TU Delft is appreciated.