Sous-sol Paris

Quarry risk pre-assessment for your address

Quarries and subsoil of Paris’s 19th arrondissement

High risk Paris 75019

The 19th arrondissement (Buttes-Chaumont, Belleville, Villette) is one of the areas most exposed to gypsum risk in Paris. Buttes-Chaumont park occupies former gypsum quarries. Two recent sinkholes (fontis) are documented there: a sinkhole (fontis) 6 m in diameter in Cité Saint-Chaumont in 2015, and a sinkhole (fontis) of approximately 10 m beneath a building at 47 rue Manin on 28 June 2020, probably caused by the failure of a foul-water collector that dissolved the subsoil gypsum.

What public data say about the 19th

Overview of the subsoil of Paris’s 19th arrondissement, based on compiled public data (IGC (Paris quarry inspectorate), Institut Paris Région, BRGM).
Underground networkGypsum quarries (Buttes-Chaumont)
Mined rockAntediluvian gypsum
Undermined areaPart of the 65 ha of Paris gypsum.
GalleriesGypsum network.
Selected risk levelHigh
Confidence in the classificationhigh
Nature of the groundBrie plateau (limestone) + gypsum of Buttes-Chaumont
Foundation issueThe risk of gypsum dissolution, aggravated by water flows, remains the area’s main geotechnical concern. A gypsum-specific study and a pipework check are recommended.

Sensitive areas of the 19th

Documented events in the 19th

  1. Late 2015

    Cité Saint-Chaumont collapse

    Cité Saint-Chaumont (19th)

    Road collapse revealing an underground cavity 6 m by 6 m, above several cavities including one 6 m high, over former gypsum quarries. A symbol of the risk of gypsum dissolution in north-east Paris.

    Source: Le Figaro — The burdensome legacy of Paris’s Swiss-cheese subsurfaces

  2. 28 June 2020

    Sinkhole (fontis) on rue Manin (Buttes-Chaumont)

    47 rue Manin (19th)

    At 47 rue Manin, on the edge of Buttes-Chaumont park, a sinkhole (fontis) around 10 m in diameter formed beneath a building, leaving only a void beneath the pavement. Suspected cause: the failure of a foul-water collector that dissolved the gypsum in the subsoil. Typical of the risk of gypsum dissolution in north-east Paris.

    Source: Journal of the Agence — Urban collapses caused by sinkholes (fontis) (D. Boussuge)

Ground, fill and clay shrink-swell

The 19th arrondissement combines the limestone of the Brie plateau and the Antediluvian gypsum of Buttes-Chaumont (see quarry section).

The risk of gypsum dissolution, aggravated by water flows, remains the area’s main geotechnical concern. A gypsum-specific study and a pipework check 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 19th before a purchase or works

High gypsum risk, exacerbated by water circulation: consultation with the IGC (Paris quarry inspectorate) is essential, along with a gypsum-specific geotechnical study and a check of the condition of pipes and drainage before 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 19th arrondissement?

Yes. The 19th arrondissement is recorded in the public data of the IGC (Paris quarry inspectorate) as an area affected by the « Carrières de gypse (Buttes-Chaumont) » network, in a rock type of Antediluvian gypsum. The risk level selected is « High », with high confidence in the classification of the area. Parc des Buttes-Chaumont occupies former gypsum quarries. Two documented recent sinkholes (fontis): Cité Saint-Chaumont (2015) and 47 rue Manin (June 2020). Belleville / Buttes-Chaumont / Villette area.

How can I find out whether my exact address in the 19th 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 19th 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 19th’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.