Mayotte

Recorded Natural Hazards (Géorisques)

It has 17 municipalities and 256,518 inhabitants. Under the seismic zoning in force since 2011, its highest seismicity is moderate (zone 3 of 5). A natural disaster has been declared 84 times since 1982 (one declaration per municipality and decree), mostly for floods (33) and earthquakes (17). The most recent was signed on 12 February 2025. 17 municipalities have a high radon potential (category 3), home to 100% of inhabitants. 7 municipalities are covered by an approved natural hazard prevention plan.

Seismicity Zones

Number of municipalities in each zone of the regulatory seismic zoning (from 1, very low, to 5, high).

Natural Disasters Declared Since 1982

Declarations per five-year period.

Most Widespread Events

• 2018Earthquakes · 10 May 201817 municipalities
• 2024Wave Impact, Coastal Flooding · 12 December 202417 municipalities
• 2024Floods and Mudflows · 12 December 202417 municipalities
• 2024Cyclonic Winds · 12 December 202417 municipalities

Most Frequently Affected Municipalities

• 7Bouéni
• 6Acoua
• 6Chiconi
• 6Kani-Kéli
• 6Ouangani
• 5Bandrele
• 5Chirongui
• 5Dzaoudzi

Hazards Listed by Municipality

Number of municipalities exposed to each natural hazard according to the departmental major risks file.

Hazards at a specific address on Géorisques

Hazard Levels

Hazard level assessed by ThinkHazard! (World Bank, GFDRR), meaning the likelihood of a damaging event, from very low to high.

• Coastal FloodHigh
• VolcanoMedium
• Extreme HeatMedium
• EarthquakeLow
• LandslideLow
• TsunamiLow
• River FloodVery Low
• Urban FloodVery Low
• WildfireVery Low

Details and recommendations on ThinkHazard!