Hénouville: geology and natural hazards

Seismic zone

1 of 5 (very low)

Radon potential

Category 1 of 3 (low potential)

Recognised natural disasters

11 since 1988

Underground cavities recorded

26

Ground movements recorded

None

Risk prevention plans

1

Natural and technological hazards to which the commune is exposed, according to the national GASPAR database.

• Inondation: par une crue à débordement lent de cours d’eau, par une crue torrentielle ou à montée rapide de cours d’eau, par ruissellement et coulée de boue, par remontées de nappes naturelles
• Mouvement de terrain: affaissements et effondrements d’origine anthropique (anciennes carrières souterraines, hors mines), affaissements et effondrements d’origine naturelle (cavités souterraines), tassements différentiels
• Risque industriel: effet toxique
• Transport de marchandises dangereuses
• Engins de guerre

11 events recognised as a natural disaster by ministerial order since 1988.

• Inondations et/ou coulées de boue: 9
• Mouvement de terrain: 2
• Chocs mécaniques liés à l’action des vagues: 1
• Sécheresse: 1

1. Inondations et/ou coulées de boue

   Event from 09/04/2024 to 11/04/2024, order published in the Journal officiel on 01/06/2024.

2. Sécheresse

   Event from 01/07/2022 to 30/09/2022, order published in the Journal officiel on 03/05/2023.

3. Inondations et/ou coulées de boue

   Event on 09/06/2021, order published in the Journal officiel on 02/07/2021.

4. Inondations et/ou coulées de boue

   Event on 02/06/2021, order published in the Journal officiel on 02/07/2021.

5. Inondations et/ou coulées de boue

   Event from 12/02/2020 to 14/02/2020, order published in the Journal officiel on 14/11/2020.

6. Mouvement de terrain

   Event from 01/02/2020 to 09/07/2020, order published in the Journal officiel on 14/11/2020.

7. Inondations et/ou coulées de boue

   Event from 07/05/2000 to 11/05/2000, order published in the Journal officiel on 21/06/2000.

8. Chocs mécaniques liés à l’action des vagues, Mouvement de terrain, Inondations et/ou coulées de boue

   Event from 25/12/1999 to 29/12/1999, order published in the Journal officiel on 30/12/1999.

9. Inondations et/ou coulées de boue

   Event on 24/12/1999, order published in the Journal officiel on 26/02/2000.

10. Inondations et/ou coulées de boue

    Event from 16/06/1997 to 17/06/1997, order published in the Journal officiel on 09/07/1997.

11. Inondations et/ou coulées de boue

    Event from 07/05/1988 to 09/05/1988, order published in the Journal officiel on 23/10/1988.

Seismic zone

Zone 1 of 5: very low. This regulatory zoning, in force since 2011, sets the rules for earthquake-resistant construction.

Radon potential

Category 1 of 3: low potential. The geological formations have the lowest uranium content. Radon is a naturally occurring radioactive gas that can build up in poorly ventilated rooms.

What BRGM maps say at the town hall. They describe that single point: elsewhere in the commune, the ground may be quite different.

• Shrink-swell clays

• Rising groundwater

• Underground cavities

• Ground movements

• Earthquakes

• Nature of the ground

Recorded across the whole commune by BRGM, in its national databases of underground cavities and ground movements.

26 underground cavities recorded (quarries, cellars, military works, natural cavities…).

No ground movement recorded (landslides, rockfalls, collapses, mudflows…).

See cavities and ground movements on the map

• PPRN-I - Seine Normande de Sotteville-sous-le-Val au Trait

  Natural risk prevention plan, under revision.

The zoning and regulations of each plan, which may prohibit or restrict building, can be consulted at the town hall and on Géorisques.

• La Vaupalière (76)
• Saint-Martin-de-Boscherville (76)
• Montigny (76)
• Saint-Pierre-de-Varengeville (76)
• Roumare (76)
• Berville-sur-Seine (76)
• Saint-Jean-du-Cardonnay (76)
• Bardouville (76)

Listed hazards, natural disasters, seismic zoning, radon potential, cavities, ground movements and prevention plans: Géorisques, published by the French ministry for the ecological transition, under Licence Ouverte Etalab 2.0, data accessed on 03/11/2026. Summary beneath the town hall: BRGM map services, queried when the page is displayed. List of communes and populations: API Découpage administratif (geo.api.gouv.fr), d’après le code officiel géographique de l’Insee, version of 30/10/2026.

This information reflects the state of knowledge at the scale of the commune or of a single point. It replaces neither a soil survey nor the official risk statement (état des risques) required for a sale or a rental, which is drawn up on the official French government service.