Subsoil and ground of Paris’s 8th arrondissement
No quarry recorded Paris 75008
The 8th arrondissement (Champs-Élysées, Madeleine) occupies an old alluvial terrace on the right bank. No known quarry is recorded by the IGC (Paris quarry inspectorate) for this arrondissement.
What the public data say about the 8th
| Underground quarries recorded by the IGC (Paris quarry inspectorate) | None |
|---|---|
| Nature of the ground | Former alluvial terrace (right bank) |
| Foundation issue | The sector is generally stable, but as elsewhere in Paris the urban subsoil may contain former made ground. A G1 geotechnical study is recommended before any construction project. |
Ground, fill and clay shrink-swell
The 8th arrondissement (Champs-Élysées, Madeleine) occupies an old alluvial terrace on the right bank. No known quarry is recorded by the IGC (Paris quarry inspectorate) for this arrondissement.
The sector is generally stable, but as elsewhere in Paris the urban subsoil may contain former made ground. A G1 geotechnical study is recommended before any construction project.
Unlike almost all French municipalities, inner Paris has no official mapping of the clay shrink-swell hazard (RGA). The BRGM explains this explicitly: the Paris subsoil is largely made up of reworked and artificial materials (backfill, infilled former quarries), which does not correspond to the standard methodology for this mapping — centred on detached houses, which are in the minority in Paris. This does not mean that there is no risk of differential settlement, but that no official area-by-area study exists for the capital: a ground investigation remains the only reliable way to assess a specific plot before purchase or construction.
Your steps to take in the 8th before a purchase or works
- IGC (Paris quarry inspectorate) information sheet — the authoritative source on the condition of the parcel’s subsoil: €10, issued within 8 days, via the City of Paris online service.
- Statutory risk statement (ERP) — mandatory for sale and letting, generated from Errial; note, it does not return cavity data in Paris.
- geotechnical survey — G1 mission before purchasing a building plot, G2 AVP before a construction or underpinning project.
- Referral to the IGC (Paris quarry inspectorate) for planning — prefectoral orders require it to be consulted for any planning permission in a quarry-risk area.
Frequently asked questions
Are there underground quarries beneath Paris’s 8th arrondissement?
No former underground quarry is listed by the IGC (Paris quarry inspectorate) for the 8th arrondissement. Areas of former quarries in Paris proper are concentrated in the south (5th, 6th, 12th, 13th, 14th, 15th, 16th, in Lutetian coarse limestone) and in the north-east (10th, 18th, 19th, 20th, in gypsum). This does not mean there are no ground-related issues: the 8th falls under the “ground and foundations” section.
Is a ground investigation still needed in the 8th?
Yes, whenever there is a construction, extension or underpinning project. The area is generally stable, but as elsewhere in Paris the urban subsoil may contain historical made ground. A G1 geotechnical study is advisable before any construction project.
Why do the 8th’s cavity data not appear on Géorisques?
Because for départements 75, 78, 91, 92, 93, 94 and 95, cavity data are not published on the Géorisques portal: they can be consulted with the IGC (Paris quarry inspectorate) for Paris and the inner suburbs, or with the relevant interdepartmental service. This is why a standard statutory risk statement (ERP) remains silent on Paris quarries and gypsum.
Is the 8th’s quarry risk covered by insurance?
Disorders linked to former quarries do not fall under the « natural disaster » scheme. In the event of collapse, infill works, estimated at 40 000 to 200 000 €, remain the responsibility of the owners. This is what makes checking before purchase essential.
Other arrondissements
- Subsoil of the 7th arrondissement
- Subsurface of the 9th arrondissement
- Subsoil of the 6th arrondissement
- Subsoil of the 10th arrondissement
- See the 20 arrondissements
Sources
- Wikipedia — Paris, Geology section
- City of Paris — Everything you need to know about the subsurfaces
- BRGM — Why is there no map of the clay shrink-swell hazard for Paris?
- Géorisques — Clay shrink-swell, 2026 version (data)
- Géorisques — Underground cavities (data)
- City of Paris — the IGC (Paris quarry inspectorate) location
- City of Paris — Known areas of former quarries (IGC)
Page updated on 11 September 2026.