Seine-Maritime

Recorded Natural Hazards (Géorisques)

It has 707 municipalities and 1,260,964 inhabitants. Under the seismic zoning in force since 2011, its highest seismicity is very low (zone 1 of 5). A natural disaster has been declared 4,380 times since 1982 (one declaration per municipality and decree), mostly for floods (2,716) and ground movements (909). The most recent was signed on 8 July 2025. 304 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

• 1999Floods and Mudflows · 25 December 1999707 municipalities
• 1999Wave Impact, Coastal Flooding · 25 December 1999707 municipalities
• 1999Ground Movements · 25 December 1999707 municipalities
• 1995Floods and Mudflows · 17 January 1995195 municipalities
• 1999Floods and Mudflows · 24 December 1999143 municipalities
• 1993Floods and Mudflows · 20 December 1993142 municipalities

Most Frequently Affected Municipalities

• 25Le Havre
• 21Dieppe
• 19Hautot-sur-Mer
• 19Yerville
• 18Duclair
• 17Rouen
• 16Terres-de-Caux
• 15Fresquiennes

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