Le Mans: geology and natural hazards

Seismic zone

2 of 5 (low)

Radon potential

Category 1 of 3 (low potential)

Recognised natural disasters

27 since 1983

Underground cavities recorded

4

Ground movements recorded

11

Risk prevention plans

2

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
• Mouvement de terrain: affaissements et effondrements d’origine anthropique (anciennes carrières souterraines, hors mines)
• Feu de forêt
• Phénomène lié à l’atmosphère
• Risque industriel: effet thermique, effet de surpression, effet de projection

27 events recognised as a natural disaster by ministerial order since 1983.

• Inondations et/ou coulées de boue: 19
• Sécheresse: 6
• Mouvement de terrain: 4
• Glissement de terrain: 1

1. Inondations et/ou coulées de boue

   Event from 08/02/2026 to 23/02/2026, order published in the Journal officiel on 13/05/2026.

2. Inondations et/ou coulées de boue

   Event on 18/06/2023, order published in the Journal officiel on 20/10/2023.

3. Inondations et/ou coulées de boue

   Event from 01/03/2020 to 03/03/2020, order published in the Journal officiel on 03/09/2020.

4. Inondations et/ou coulées de boue

   Event from 09/06/2018 to 11/06/2018, order published in the Journal officiel on 15/08/2018.

5. Inondations et/ou coulées de boue

   Event from 04/06/2018 to 05/06/2018, order published in the Journal officiel on 15/08/2018.

6. Inondations et/ou coulées de boue

   Event on 28/05/2016, order published in the Journal officiel on 12/08/2016.

7. Sécheresse

   Event from 01/07/2009 to 30/09/2009, order published in the Journal officiel on 06/04/2011.

8. Inondations et/ou coulées de boue

   Event on 27/07/2006, order published in the Journal officiel on 04/05/2007.

9. Sécheresse

   Event from 01/07/2005 to 30/09/2005, order published in the Journal officiel on 22/02/2008.

10. Inondations et/ou coulées de boue

    Event on 23/06/2005, order published in the Journal officiel on 22/04/2006.

11. Sécheresse

    Event from 01/07/2003 to 30/09/2003, order published in the Journal officiel on 13/12/2005.

12. Inondations et/ou coulées de boue

    Event on 25/06/2003, order published in the Journal officiel on 19/10/2003.

13. Mouvement de terrain

    Event from 23/03/2001 to 31/03/2001, order published in the Journal officiel on 28/04/2001.

14. Inondations et/ou coulées de boue

    Event from 23/03/2001 to 25/03/2001, order published in the Journal officiel on 28/04/2001.

15. Inondations et/ou coulées de boue

    Event from 05/01/2001 to 07/01/2001, order published in the Journal officiel on 23/02/2001.

16. Inondations et/ou coulées de boue, Mouvement de terrain

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

17. Inondations et/ou coulées de boue

    Event from 17/01/1995 to 31/01/1995, order published in the Journal officiel on 08/02/1995.

18. Inondations et/ou coulées de boue

    Event on 05/08/1994, order published in the Journal officiel on 24/11/1994.

19. Inondations et/ou coulées de boue

    Event on 24/07/1994, order published in the Journal officiel on 24/11/1994.

20. Glissement de terrain

    Event from 04/02/1994 to 04/02/1995, order published in the Journal officiel on 09/09/1995.

21. Sécheresse

    Event from 01/01/1993 to 31/03/1997, order published in the Journal officiel on 28/03/1998.

22. Inondations et/ou coulées de boue

    Event from 05/12/1992 to 06/12/1992, order published in the Journal officiel on 21/01/1994.

23. Sécheresse

    Event from 01/01/1991 to 31/12/1992, order published in the Journal officiel on 03/09/1993.

24. Sécheresse

    Event from 01/06/1989 to 31/12/1990, order published in the Journal officiel on 30/08/1991.

25. Inondations et/ou coulées de boue

    Event from 06/04/1985 to 10/04/1985, order published in the Journal officiel on 27/07/1985.

26. Inondations et/ou coulées de boue, Mouvement de terrain

    Event from 25/06/1983 to 26/06/1983, order published in the Journal officiel on 18/11/1983.

27. Mouvement de terrain, Inondations et/ou coulées de boue

    Event on 21/06/1983, order published in the Journal officiel on 18/11/1983.

Seismic zone

Zone 2 of 5: 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.

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

11 ground movements recorded (landslides, rockfalls, collapses, mudflows…).

See cavities and ground movements on the map

• PPRi-Sarthe agglo du Mans - REVISION

  Natural risk prevention plan, under revision.

• PPRT SDPS - Le Mans

  Technological risk prevention plan.

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

• Coulaines (72)
• Saint-Pavace (72)
• La Chapelle-Saint-Aubin (72)
• Sargé-lès-le-Mans (72)
• Rouillon (72)
• Allonnes (72)
• Yvré-l’Évêque (72)
• Trangé (72)

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 02/11/2026. 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.