Adaptation measures to address the risk of coastal erosion

The report examines why coastal-erosion risks in New Caledonia are increasing and how public authorities currently respond. It reviews the state of knowledge, including the role of the Coastal Observatory (OBLIC), the legal and institutional framework for prevention, and the distribution of responsibilities across provinces, municipalities and customary lands. New Caledonia faces accelerating coastal erosion and sea‑level rise, with 71% of its 5,900 km coastline exposed to retreat, threatening communities, infrastructure, freshwater resources and economic activities. The publication is intended for policymakers, local authorities, customary leaders, technical agencies and development partners seeking to understand the scale of the hazard, the gaps in governance and the need for integrated climate‑risk management across New Caledonia. Disaster risk reduction is central throughout, with explicit focus on hazard mapping, prevention planning, protective infrastructure, nature‑based solutions and long‑term adaptation strategies.

The report concludes that responses remain fragmented, under‑resourced and insufficiently aligned with the emerging climate strategy. It recommends strengthening OBLIC to coordinate knowledge and monitoring; developing natural disaster prevention plans to delineate exposed areas and guide land‑use decisions; clarifying rules for applying such plans on customary lands; and establishing a dedicated territorial fund, similar to France’s Barnier Fund, to finance protective and relocation measures. Lessons emphasise the need for improved coordination between provinces and municipalities, better integration of coastal erosion into climate policy, and adaptive planning that can evolve with new scientific insights. The report highlights that sustainable solutions will require combining structural protection, nature‑based approaches, community engagement and long‑term strategic planning to reduce vulnerability and build resilience across the territory.