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Beach nourishment - the case of Orfordness
Orfordness poses a dilemma for both coastal
defence authorities and conservationists. A breach in the spit at
Slaughden at the northern end of Orfordness meant that 250,000 m3 of shingle
was transported from the Ness to fill the gap (Kinsey
1981). The King's Marshes were also bulldozed towards the shore to raise
the sea defences. Both courses of action restricted the width of the beach,
such that a minor breakthrough could quickly become much worse. Just below Aldeburgh,
the river has cut into the landward side of the spit, while the sea erodes the
outer shore because defence works further north starve the shoreline. Holding
the line at this point of the coast is only possible by beach feeding (see Annex
06 for details of the location and some of the consequences).
Over the years these coastal defence works have caused damage to the ecology
of the area, notably around the shingle extraction area towards the north of
the site. It would be very helpful to carry out detailed modelling to ascertain
the affect of ceasing beach feeding and leaving this site to nature. Would losses
be that great? Is the present practice sustainable? The situation at Orfordness
may be quite similar to that at Dungeness in the Middle Ages. Left to itself
the Alde would eventually break through as the Rother once did there (Steers
1969), leaving the ness to continue its migration southwards.
Recommendation: Allowing this process to occur might be a cost-effective
solution to the sea defence problem that currently exists. It would allow the
coast to develop naturally and could help regenerate damaged surface shingle
further south. Undertake predictive modelling on the geomorphological implications
of leaving certain sites to nature e.g. ceasing beach feeding at Slaughden (Orfordness,
Annex 06).
References
Kinsey, G.
1981.
Orfordness: Secret Site; a History of the Establishment 1915-1980. Dalton, Lavenham, Suffolk.
Steers, J.A.
1969.
The Coastline of England and Wales, 2nd Edition. Cambridge University Press, 762 pp.
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