Quarries and subsoil of Paris’s 10th arrondissement

Moderate risk Paris 75010

The 10th arrondissement (gare du Nord, gare de l’Est, Saint-Vincent-de-Paul) is affected by former gypsum quarries, which cover 65 hectares across the 10th, 18th, 19th and 20th arrondissements. Unlike limestone, gypsum is soluble in water: its gradual dissolution, often triggered by pipe leaks, creates cavities and sinkholes (fontis). Voids were discovered beneath gare du Nord (1975) and gare de l’Est (1970).

What public data say about the 10th

Summary of the subsoil of Paris’s 10th arrondissement, based on compiled public data (IGC, Institut Paris Région, BRGM).
Underground network	Gypsum quarries (north-east)
Mined rock	Antediluvian gypsum
Undermined area	Part of Paris’s 65 ha of gypsum (10th, 18th, 19th, 20th).
Galleries	Gypsum network (length not published by arrondissement).
Selected risk level	Moderate
Confidence in the classification	high
Nature of the ground	Gypsum area (north-east) + station made ground
Foundation issue	As gypsum is soluble in water, any ground investigation must check for the absence of active dissolution as well as the nature of the made ground. A G1/G2 geotechnical study and monitoring of water networks are recommended.

Sensitive areas of the 10th

Gare du Nord, Gare de l’Est, Saint-Vincent-de-Paul sectors
Sinkhole (fontis) beneath Gare de l’Est (1970) and void pocket beneath Gare du Nord (1975)

Documented events in the 10th

1970
Sinkhole (fontis) beneath Gare de l’Est
Gare de l’Est (10th)
Detection of a sinkhole (fontis) — a void of 7 300 m³ — beneath gare de l’Est, immediately filled in.
Source: Le Parisien — Beneath the cobblestones, the void (2001)
1975
Void pocket beneath Gare du Nord
Gare du Nord (10th)
During the excavation of RER B, a void pocket 15 m high and 15 m in diameter, linked to gypsum dissolution, was discovered. Urgently backfilled.
Source: Le Figaro — The burdensome legacy of Paris’s Swiss-cheese subsurfaces

Ground, fill and clay shrink-swell

The 10th arrondissement is in an Antediluvian gypsum zone (see quarry section), and its subsurface is also marked by former low-lying levels and substantial infill around the major stations (gare du Nord, gare de l’Est).

As gypsum is soluble in water, any ground investigation must check for the absence of active dissolution as well as the nature of the made ground. A G1/G2 geotechnical study and monitoring of water networks are recommended.

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 10th before a purchase or works

Gypsum risk: gypsum is soluble in water, dissolution is progressive and often triggered by leaks from pipes. An IGC (Paris quarry inspectorate) information request (10 €) is essential before purchase or works. A gypsum-specific geotechnical study is recommended.

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 10th arrondissement?

Yes. The 10th arrondissement is recorded in public data from the IGC (Paris quarry inspectorate) as an area affected by the « Gypsum quarries (north-east) » network, in Antediluvian gypsum. The risk level selected is « Moderate », with high confidence in the sector classification. Gypsum, mined for plaster, is soluble in water: progressive dissolution creates cavities and sinkholes (fontis). The 10th is one of Paris’s 4 gypsum arrondissements (10th,18th,19th,20th — 65 ha in total).

How can I tell whether my exact address in the 10th is in an undermined area?

Quarry zoning must be read at plot level rather than arrondissement level. There are two options: the official information sheet from the IGC (Paris quarry inspectorate), at €10 and issued within 8 days, which is the legally binding source; and Sous-sol Paris’s instant pre-assessment, at €15, which matches your address against public data and immediately provides you with a readable report, including the steps to take. This pre-assessment is for information only and does not replace the IGC information sheet, the statutory risk statement (ERP), or a geotechnical study.

Why do cavity data for the 10th 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 quarry risk in the 10th 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.