Key natural hazards and issues in this study area: Erosion of the sandy coast is important around the urbanised river outlets, where the efficiency of existing defences needs to be examined. The river outlets and backshore floodplains are subject to marine flooding hazard.

In the south, the cliffs of the Pays-Basque area are affected by instability and erosion, mainly due to rock weathering and ground water fluctuations, providing little sediment supply to the fringing beaches. Erosion and marine flooding affects the developed areas and is likely to increase in the coming decades.

Mapping and investigation by: BRGM, Orleans, France:
C.VINCHON (BRGM/ARN) (following L.CLOSSET BRGM/ARN): Head of the French participation in the Project, Co-ordination, synthesis and reporting.
D.IDIER, M.GARCIN (BRGM/ARN): Data collecting and GIS elaboration. Map realisation.
C.MALLET, S.AUBIE (BRGM/AQUI): Regional expertise and validation.

Key messages:
An increase in levels of risk on the coast is expected based on climate change hypotheses;
There is relative adaptation capacity on the sandy coast, except at low points (river outlets);
Coastal development planning must integrate the hypothesis of climate change.