Coastal Proecesses

Coastlines, geomorphology and coastal processes analysis

Coastlines, geomorphology and coastal processes analysis fall under the same umbrella and are very closely linked. Morphodynamics encompasses the understanding of both coastal landforms (i.e. geomorphology) and the range of forces (such as waves, tides, winds and currents) that may be applied to the landforms. Examples of landforms include:

beaches (sand and shingle) spits/nesses cheniers estuaries

inlets levees cliffs and wave-cut platforms

In order to make strategic decisions on coastal management, land-use planning, or to design and construct a coastal structure, it is vital to have a full understanding of the coastal processes taking place, how coasts and coastal sediments respond to the forces that act upon them and a knowledge of predictions (or estimates) of long-term future coastal evolutionary tendency. With this information, it is possible to design a structure that will withstand the natural forces, such as wind, waves and tide; development plans for the coastline, whilst simultaneously work as best as possible with the natural environment.

Coastal process analysis involves the interpretation of model outputs, management and interpretation of survey data/beach monitoring data. The study of coastal processes and shoreline geomorphology link very closely to numerical and physical modeling. Problems such as chronic erosion, storm and flood damage, erosion adjacent to improved navigation projects, and wetlands creation and protection are studied using the most appropriate combination of analytical, numerical, and physical modeling technologies3.

Data Acquisition

Data acquisition involves the development, testing, deployment, maintenance and operation of water resource and environmental instrumentation systems. Data acquisition is useful to support hydraulic structures, harbor design and monitoring, dredging, beach nourishment, inlet channel maintenance, land and hydrographic surveying, long term environmental modeling, navigation effects monitoring, vessel tracking and sediment analysis2.

Numerical Modeling

Construction work in the coastal zone can have significant impacts upon the hydrodynamics in the immediate and more distant surrounding water. These impacts can be in terms of changes to the tidal flows, water levels and/or wave climate. Additionally it is important to predict future impacts due to climate changes and extreme conditions so that these can be taken into account when designing structures/defenses. Numerical and physical modeling encompasses all of these areas both in terms of the application of numerical models and the understanding of the underlying processes (i.e. sediment movement and shoreline erosion).

Shoreline & Strategic Planning

The potential for actions on the coastline to have impacts on other parts of the coastal zone (alongshore and offshore) has long been recognized. To take account of this, management of the coast is undertaken within a strategic framework whereby decisions are based upon an understanding of all factors that could be affected, from a high level, which determines possible options to low-level, which determines how these options can be implemented. These factors include:

• Coastal zone management
• Shoreline management plans
• Policy appraisal
• Strategic planning
• Policy and legislation
• Stakeholder engagement (the engagement of stakeholders within the decision making process is key to the success of coastal management)
• Economic assessment

 

2 http://chl.erdc.usace.army.mil/ Last accessed 17th September 2008.

3 http://chl.erdc.usace.army.mil/ Last accessed 17th September 2008.