Coastal protection

EN 13253, Geotextiles and geotextile-related products. Characteristics required for use in erosion control works (coastal protection, bank revetments), 2001. 

The coasts of Odessa Bay are presently eroded and their condition is defined by landslide and caving processes widely developed on the steep coastal slopes. Here, the heights of the cliffs sometimes exceed 30 m. Intensive engineering coastal protection is performed. 

Dean, R.G. 2005. Beach Nourishment Benefits, Theory and Case Examples. NATO Science Series, Environmentally Friendly Coastal Protection. 

When using economic risk based curves in decision making it should be note that the chosen solutions should never be on the right side of the interaction point between the risk and investment curves. Because, from the economic investment point of view, the solution is not worth as the risk is higher than the cost of the system. In this considered example for Nam Dinh case, selection of the design return periods of less than 30 years leads to very high risk and is therefore a bad choice in this situation. Selection from 50 to 100 years return period is, therefore, recommended for the future planning of coastal protection in Nam Dinh. Invest... 

Figure 4.2. Storm damage to coastal protection site Figure 4.3. Jack-up platform working in exposed wave conditions in Sennen Cove (courtesy Seacore)...

Artificial replenishment ot the shore by building beach tills is used either if it is economically preferable or if artificial barriers fail to defend the shore adequately from erosion. In fact, beach nourishment represents the only form of coastal protection that does not adversely affect other sectors of the coast. Unfortunately, it is often difficult to predict how frequently a beach should be renourished. Ideally, the beach fill used for renourishment should have a similar particle size distribution as the natural beach material. 

Although the study of coastal erosion is a fundamental concept for coastal engineering, coastal engineers must also recognize and study coastal protection measures and applications such as hard and soft shoreline protection structures, understand the effects of these structures on the morphology of the coastal areas, and develop effective coastal zone management plans and policies. 

In the past, the development of wave damping structures used in coastal protection and harbor engineering was rather directed toward achieving a maximum reduction of wave height in the sheltered area, while less attention was generally paid to further performance aspects such as... 

Submerged wave absorber as artificial reef for coastal protection... 

An interesting cost effective and soft alternative to conventional seawalls for coastal protection against erosion are artificial reefs which have the advantage... 

The relatively low crest level and the discontinuous nature of the barrier resulted from the requirements that, for the tourists on the promenade the view to the sea and the direct access to the shoreline should not be obstructed. Moreover, the barrier should architecturally and aesthetically fit into the local landscape, so that it will not necessarily be perceived as a coastal protection structure [Fig. 12.18(a)]. The efficiency of the OWED concept in terms of wave overtopping reduction was successfully tested in the Large Wave Flume (GWK) in Hannover [Figs. 12.18(b) and 12.18(c)] and implemented in Norderney [Fig. 12.18(d)], where it withstood without any damage several storm surges for more than five years. 

H. Oumeraci and G. Koether, Hydraulic performance of a submerged wave absorber for coastal protection. Advances in Coastal Ocean Engineering (2008), pp. 36 (in print). 

T. L. Andersen and H. F. Burcharth, Landward distribution of wave overtopping for rubble mound breakwaters, Proc. First Int. Conf. Application of Physical Modelling to Port and Coastal Protection (2006). 

K. W. Pilarczyk (ed.), Coastal Protection (A.A. Balkema, Rotterdam, 1990), www.enwinfo.nl (select Enghsh, downloads). 

Appendix A. Comparative Stability of Revetments (Pilarczyk, 1990, Coastal Protection)... 

Some coastal environments may be regarded as rather stable (rock and reef coasts) while others are more vulnerable (sand and mud coasts, soft cliffs). In this last case, coastal users and managers aU over the world are frequently faced with serious erosion of their sandy coasts. Possible causes of erosion include natural processes (i.e., action of waves, tides, currents, sea level rise, etc.) and sediment deficit due to human impact (i.e., river regulations, sand mining, and coastal engineering works). Countermeasmes for beach erosion control function depend on local conditions of shore and beach, coastal chmate, and sediment transport. Continuous maintenance and improvement of the coasthnes, together with monitoring and studies of coastal processes have yielded considerable experience on various coastal protection measures all over the world. 

This contribution presents an overview of the various available methods for shore stabilization and beach erosion control, with special emphasis on the novel/alternative systems in various design implementations. More detailed information on other coastal protection systems and measures applied nowadays throughout the world can be found in extensive list of references. > 6,51,52,54,80... 

Coastal Protection Methods (an overview) Sand (problem) Action Measure... 

These new systems were applied successfully in number of countries and they deserve to be applied on a larger scale. Because of the lower price and easier execution, these systems can be a good alternative for traditional coastal protection/ structures. The main obstacle in their application is, however, the lack of proper design criteria. An overview is given on application and performance of some existing novel systems and reference is made to the actual design criteria. Additional information on these systems can be in references and on websites. 

Low-crested and submerged structures (LCS) as detached breakwaters and artificial reefs are becoming very common coastal protection measures (used alone or in combination with artificial sand nourishment).As an example, a number of systems and typical applications of shore-control structures is shown in Figs. 20.4-20.7. 

Offshore breakwaters and reefs can be permanently submerged, permanently exposed or inter-tidal. In each case, the depth of the structure, its size, and its position relative to the shoreline determine the coastal protection level provided by the structure. To reduce the cost some alternative solutions using geosystems can be considered. The actual understanding of the functional design of these structures needs further improvement but may be just adequate for these structures to be considered as serious alternatives for coastal protection. 

K. Black and S. Mead, Submerged structures for coastal protection, ASR, Marine and Freshwater Consultants, New Zealand (1999) (www.asrltd.co.nz). 

S. Restall et al., Australian and German experiences with geotextile containers for coastal protection, 3rd EuroGeo, Munich, Germany (2004). 

S. J. Restall, W. P. Hornsey, H. Oumeraci, M. Hinz, F. Saathoff and K. Werth, Australian and German experiences with geotextile containers for coastal protection, Proc. Euro-Geo 3, Munich, Germany (2005), pp. 141-146. 

Marine Engineering Part of the Proceedings of the Institution of Civil Engineers (1741-7597). Started in 2004 by the ICE, this journal publishes papers that focus on such topics as fixed and moving port and harbor developments, estuarine and coastal protection, habitat creation, and seabed pipelines. 

Clean Water Report (0009-8620) (1545-7435). This journal provides comprehensive coverage of drinking water and sewer systems, lakes, rivers and streams, coastal protection, tributaries and bays, as well as the Safe Drinking Water Act, the Clean Water Act, and other major legislative initiatives. It also includes articles on biosolids, pathogens, arsenic, chlorine, dioxin, and other pollutants, problems snch as flooding, silting, sedimentation, nutrients, and more. 

Geotextiles are those fabrics used in geotechnical applications, such as road and railway embankments, earth dikes, and coastal protection structures, designed to perform one or more basic functions such as filtration, drainage, separation of soil layers, reinforcement, or stabilisation. Therefore, almost every geotextile application is multifunctional. 

Graaff, J. Van de. Coastal Morphology and coastal protection, draft, September 2006. 

Agerschou, H.A., February 1961. Synthetic material filters in coastal protection. Journal of the Waterways and Harbors Division, ASCE 87 (WWl), 111—124. 

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