Natural realignment on shingle shores

Natural realignment is a rare phenomenon in shingle beaches and structures in the south and east of the UK where gravel beaches protect agriculture or other 'valued' asset. The problem relates to the lack of available land over which any movement of a gravel beach can take place. Where it is feasible, as a rule of thumb for every 1mm of relative sea level rise a set-back line of 50m would be required to accommodate any retreat over a 50 year period (Orford et al. 2001). Note at Porlock Weir there was a 40m landward transgression during one storm. This emphasises the periodic nature of change, especially in coastal systems and the need to take a long term perspective on coastal realignment.

References

Orford, J.D., Jennings, S.C. & Forbes, D.L. 2001. Origin, development, reworking and breakdown of gravel-dominated coastal barriers in Atlantic Canada: future scenarios for the British coast. In: Ecology & Geomorphology of Coastal Shingle, eds.Packham, J.R., Randall, R.E., Barnes, R.S.K. & Neal, A.Westbury Academic and Scientific Publishing, 23-55.