The partner interview

What are the main natural risks in La Réunion and how can they be prevented?

Patrice Latron —  La Réunion is an exceptional but highly vulnerable territory, which is exposed to seven major risks: cyclones, floods, landslides, volcanic eruptions, forest fires, earthquakes and tsunamis. Its steep terrain and heavy tropical rains exacerbate the risks associated with gravity-related hazards, such as landslides. Prevention measures are based first and foremost on scientific knowledge and good spatial planning, notably through the creation of risk prevention plans (PPRs) and the deployment of monitoring systems, but also by ensuring a responsible approach to land use and planning. Recent crises have shown that a significant proportion of landslides are linked to human activities, notably due to failing infrastructures or poor rainwater management. Adapting construction practices is therefore a priority.

Can you explain how BRGM helps to prevent these risks and manage cyclone-related crises, such as during Hurricane Garance in 2025?

P. L. — BRGM’s expertise is essential for providing factual data for public decision-making and ensuring safety. During Cyclone Garance, the organisation responded in exemplary fashion to the crisis: 135 on-site assessments led to recommendations being made for 116 homes, including 20 permanent evacuations and 77 precautionary evacuations. A satellite survey identified 521 areas of instability. This work enabled the Government to target specific safety measures and support local authorities in relocating homes at risk.

BRGM has had a branch in La Réunion for over fifty years and has significantly improved the geological understanding of the island. Which areas of work are priorities today?

P. L. — In the face of increasingly extreme weather events linked to climate change, the priorities are: protecting the population by drawing on the lessons learnt from cyclones Belal and Garance and integrating the data into the Risk Prevention Plans (PPRs), anticipating coastal risks and managing existing threats; improving the management of water resources through better assessment and protection of groundwater; the energy transition and the continuation of deep geothermal exploration programmes; sustainable development, and notably the consolidation of the circular economy through the regional quarrying plan and by combating soil erosion in order to protect our coral reefs and our biodiversity. The synergies that exist between BRGM and the local authorities, local councils and research organisations must be maintained and consolidated in order to make La Réunion a model in terms of risk management and sustainable development.