Sea level rise is already reshaping France’s Atlantic, Channel, and Mediterranean coastlines.

Since 1975, sea levels have risen by 10–15 cm, leading to increased beach erosion, storm-surge flooding, and saltwater intrusion into wetlands and farmland. The deadly Xynthia storm in 2010 demonstrated that many low-lying communities are already highly vulnerable.

Projections show a further 15–25 cm rise by 2050, and up to one meter by 2100 if global emissions remain high. This would lead to permanent flooding in certain coastal areas and more frequent damage to homes, ports, and roads. Popular regions such as Nouvelle-Aquitaine, Brittany, and the Camargue are already experiencing noticeable shoreline retreat.

These changes have major consequences for property and insurance. Homes near the coast are becoming more expensive and sometimes impossible to insure, as France’s national disaster insurance system (CatNat) faces more frequent and costly claims. In some of the most exposed areas, property values are beginning to fall — a sign of early climate-driven migration inland.

To adapt, France is investing in a mix of protective and preventive measures. Strengthening existing sea walls and dunes is underway in vulnerable municipalities. Restoring wetlands can absorb storm surges naturally. National adaptation plans estimate that coastal protection efforts will cost between €1.5 and €3 billion by 2030, and likely more than €5 billion by 2050 as sea levels continue to rise. These investments take years to plan and build — but acting early is significantly cheaper than recovering from repeated disasters.

Authorities are also updating urban planning rules. New zoning laws restrict development in areas designated as “coastal retreat zones,” and several communities are now preparing managed retreat strategies to relocate homes and infrastructure away from the sea gradually.

Given the escalating risk and financial burden, France will need strong limits on future coastal property development, especially in low-elevation areas where flooding will become chronic. Supporting people and communities in relocating inland — before emergencies force them to — will help ensure safe and sustainable coastal living in the long term.

Sea level rise is no longer a distant threat: it is shaping real estate, insurance, and community planning today. Early and strategic adaptation will protect both coastal residents and the French coastline itself.

This Post was submitted by Climate Scorecard France Country Manager, Camille Huret.