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 Scientific Research, Consultancy and Investigations

              
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Assessment of beach nourishment in Lincolnshire
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Project funded by the Environment Agency and Natural Environment Research Council

Beach nourishment is increasingly seen as an appropriate management solution in areas which are experiencing beach erosion.  Such a scheme has been implemented along the Lincolnshire coast between Skegness and Mablethorpe, on the east coast of England, since 1994.  Poorly sorted, gravelly sandy sediment has been placed on the beaches in a gently sloping seaward profile to raise beach levels and protect the hard defences from wave attack.

Mablethorpe before nourishment, 1994     Mablethorpe after nourishment, 1999
       The beach at Mablethorpe before nourishment                      The beach at Mablethorpe after nourishment

Grain size analysis of  beach sediments, topographic profiling and remote sensing was used to monitor the beach response.  After nourishment, wave reworking caused a rapid redistribution of sediment over the beach profile during the succeeding weeks.  Coarse sediment remained on the beach berm, while finer sediment migrated to the lower beach and sub-tidal zone.  The berm face correspondingly became steeper, producing more wave reflectance, and further scour and erosion of lower beach sediment, although there was little alongshore sediment transport.  The most severe sediment loss occurred around promontories and on the central portion of the convex-shaped coast which experiences greatest wave exposure.

DTM of Ingoldmells, Lincolnshire, using lidar data   Particle size distribution on the Lincolnshire coast  
Digital terrain model of the beach near                       Cross-shore variation in particle size distribution
Ingoldmells in 2000 generated from lidar data

 

Redistribution of beach material on the Lincolnshire coast
Model showing redistribution of beach material after nourishment

While the nourishment scheme has improved the standard of defence, this study concluded that further sediment losses could be reduced by nourishing the beach with a more natural size grading, promoting a flatter beach profile and increasing the dissipation of wave energy.  Unless stabilization of the beach profile can be achieved, further periodic renourishment will be required to maintain relatively high beach levels.

 

Publications and Reports

Blott, S.J. and Pye, K. (2004). Morphological and sedimentological changes on an artificially nourished beach, Lincolnshire, UK. Journal of Coastal Research 20, 214-233.
(click to view the abstract of this paper)

Blott, S.J. (2002). Morphological and Sedimentological Changes on Artificially Nourished Beaches, Lincolnshire, UK. PhD Thesis, University of London, 422 pp.

Blott, S.J. (2001). Sedimentological changes on artificially nourished beaches in Lincolnshire, UK. SPME, Royal Holloway, University of London, Research Report CS12, 56 pp.


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Page last modified: October 03, 2007