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Wednesday 24 January 2018

GROYNES & LONGSHORE DRIFT

GROYNES AND LONGSHORE DRIFT

Weathered groynes at Winchelsea Beach

In a previous entry I've talked about the winter task of moving shingle back from Rye Harbour to Pett Level. And, if it wasn't for the groynes, it would return much quicker. 


This constant movement is caused by longshore drift. I quote,

'Longshore sediment transport/Littoral drift is a geological process that consists of the transportation of sediments (clay, silt, sand and shingle) along a coast parallel to the shoreline, which is dependent on an oblique incoming wave direction.'

Groynes buried in shingle, high up the beach

In effect, this means that, in our case, shingle is carried the five or so miles, along the coast from Cliff End to the breakwater at Rye Harbour. Wooden groynes, placed at right-angle to the shoreline, constructed from stout timbers, are positioned every 80 -100 metres. These have the effect of holding the shingle back, thus slowing the effect of the longshore drift.

Groynes battered by the sea, Cliff End.








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