Seine to the Somme

Cayeux sur Mer lies at the end of a major 'drift cell' which stretches from the Seine to the Somme. In some ways the coastline is similar to that on the English side of the Channel which stretches from Selsey Bill to the Dungeness to Pett Levels CHaMP. The material for the shingle structure is derived from cliff erosion and longshore drift from the west to east. This source has been significantly depleted by artificial structures and gravel extraction. The resulting impact on the coast create significant problems in areas adjacent to those which are 'protected' as the available material for 'natural' defences is severely depleted.