Sous-sol Paris

Quarry risk pre-assessment for your address

Subsoil and ground of Paris’s 2nd arrondissement

No quarry recorded Paris 75002

The 2nd arrondissement (Bourse) occupies an old alluvial terrace slightly above the Seine riverbed, urbanised since the Middle Ages. No known quarry is recorded by the IGC (Paris quarry inspectorate) for this arrondissement.

What the public data say about the 2nd

Summary of the subsoil of Paris’s 2nd arrondissement, based on compiled public data (IGC, Institut Paris Région, BRGM).
Underground quarries recorded by the IGC (Paris quarry inspectorate)None
Nature of the groundOld terrace / Tertiary plateau
Foundation issueThe area is generally stable at depth, but the dense urban subsoil contains fill and remains of previous buildings. A G1 ground study remains advisable before any construction or extension project.

Ground, fill and clay shrink-swell

The 2nd arrondissement (Bourse) occupies an old alluvial terrace slightly above the Seine riverbed, urbanised since the Middle Ages. No known quarry is recorded by the IGC (Paris quarry inspectorate) for this arrondissement.

The area is generally stable at depth, but the dense urban subsoil contains fill and remains of previous buildings. A G1 ground study remains advisable before any construction or extension 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.

Steps to take in the 2nd before a purchase or works

  1. 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.
  2. Statutory risk statement (ERP) — mandatory for sale and letting, generated from Errial; note, it does not return cavity data in Paris.
  3. geotechnical survey — G1 mission before purchasing a building plot, G2 AVP before a construction or underpinning project.
  4. 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 2nd arrondissement?

No former underground quarry is recorded by the IGC (Paris quarry inspectorate) for the 2nd arrondissement. Former quarry areas in inner Paris 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 that there are no ground-related issues: the 2nd falls under the « ground and foundations » section.

Is a soil study still needed in the 2nd?

Yes, whenever there is a construction, extension or underpinning project. The area is generally stable at depth, but the dense urban subsoil contains made ground and remains of previous buildings. A G1 ground investigation remains advisable before any construction or extension project.

Why do the 2nd’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 2nd’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

Sources

Page updated on 11 September 2026.