Share on Google+Tweet about this on TwitterShare on LinkedIn

XBeach-G protects coasts

XBeach-G model helps to protect gravel coasts

XBeach-G model helps to protect gravel coasts like the Chesil Beach, as seen at Chesil Cove, Dorset (England)

XBeach-G model helps to protect gravel coasts in the United Kingdom against storms and rising sea levels. 

Gravel beaches are widely considered as an effective and sustainable form of coastal defense. Until now, there has been little research done, understanding the mechanisms leading to their failure during storms.

That’s why coastal managers have very limited guidance when estimating the potential for flooding on gravel coasts.

 

XBearch G model

Morphological response of a gravel barrier (red line) when waves become more energetic and the water level rises

XBeach-G simulation model

The new XBeach-G model simulates the impact of storms on gravel beaches and barriers by solving the hydrodynamics of individual waves:

  • in the nearshore and swash zone
  • wave run-up and overtopping flows
  • groundwater processes in the beach and barrier
  • sediment transport
  • and morphological change of the beach during the storm

Accurate

The model represents a substantial improvement over existing empirical models in its ability to accurately simulate the response of gravel beaches to a wide variety of storms.

  • A new algorithm makes it is possible to extract the required information from satellite data, without heavy downloads or local calculation capacity.
  • This information is combined with knowledge about the flow of water and open GIS data.
  • The research was performed based on two locations: Mekong river delta in Vietnam and Murray-Darling basin in Australia.

The model has increased our understanding of the role of incident-band and infragravity-band waves during storms, and the role of groundwater processes in the stability of gravel beaches and barriers.

Easy-to-use interface

To ensure easy uptake of the XBeach-G model by coastal managers and engineering firms, Deltares and Plymouth University have developed a free and easy-to-use graphical user interface (GUI) for the XBeach-G model.

  • Deltares and Plymouth University have given training and assistance to 40 interested parties in the UK and the Netherlands.
  • The XBeach-G model, model GUI, and validation papers are freely available at the XBeach-G website.

Gravel defences

Dredging companies use gravel to set up temporarily defenses. They can also use the model for the design of these defenses. A well-known gravel beach is 29 km long and almost 15 meters high Chesil Bank, Dorset, England. During a big storm in 2014 the data was collected at this beach and used to develop and validate XBeach-G.

Gravel coasts are common in the United Kingdom, Italy, Croatia, Georgia, Ukraine (Mediterranean and Black sea), Ireland, Estonia, Latvia, Australia and New Zealand, United States, Canada, Argentina, Chile and Japan.

Collaboration and impact

Coastal morphology expert Robert McCall Plymouth University and several governmental and private partners, including Deltares, Channel Coastal Observatory, Environment Agency, HR Wallingford and Unesco-IHE.

One of the key scientific papers discussing the development of the XBeach-G model was awarded the Halcrow Prize for the best paper published in the ICE journal Maritime Engineering.

Link to the XBeach-G model

Coastal Morphology

 

The ongoing rise in the relative sea level due to the glacial melting since the last ice age and now perhaps accelerated by the Greenhouse Effect creates a pervasive mechanism for shoreline retreat.

Numerous devices have been devised to stop the erosion process. These can be divided into two basic types: hard and soft structures.

  • Hard structures have been the traditional tool of the coastal engineer. These include groins (structures oriented perpendicular to the shoreline to slow the transport of sand along a shoreline), jetties (placed at inlets to keep sand from the navigational channel, breakwaters (to reduce wave action in harbours), and sea walls (to prevent the erosion of the upland).
  • Soft structures are those that are more natural. The primary example is beach nourishment, which is the placement of sand on an eroding beach. Nourishment is a short-term measure as it does not fix the cause of the erosion; however, it is the only method that involves adding sand to the coastal system.
    The second innovation in nourishment after the innovative introduction of shoreface nourishments in the mid 1990’s is the Sand Motor on the Dutch coast created in 2011.

Related

Have you seen this?

Flood Solutions – Flood Risk Management

New dossier: Flood Risk Management for Industries and Flood Solutions

BetterWorldSolutions helps you finding qualified leads and sales partners, world wide

Sign Up

or

mail to: info@betterworldsolutions.eu

 

Leave a Reply

Your email address will not be published.