Wells and Piezometers: New Requirements

🔎 Things to remember

The regulatory framework governing non-domestic surveys, drilling, wells, and piezometers has been strengthened by two executive orders dated March 18, 2026.
Operators must use a “CertiForage”-certified company for certain excavation and backfilling work.
The requirements are specified for the entire lifecycle of the structure: administrative procedures, technical standards, maintenance, inspections, incident management, and reporting.

Whenever a hole of a certain depth is drilled into the ground—for example, to reach an aquifer as part of water extraction drilling or to monitor the quality of that aquifer using piezometers, or to reach a geothermal reservoir—there is a risk of soil or groundwater contamination (e.g., pollution related to industrial operations, accidental pollution, flooding, etc.) may arise… Consequently, these projects are subject to specific regulations and monitoring.

A quick update on the latest rules in effect.

‍

Regulatory Context

Until 2025, drilling services performed during the start of operations or during the decommissioning of a geothermal field of minor importance had to be carried out by certified companies. At the same time, the decree of September 11, 2003, established the requirements applicable to surveys, drilling, and the construction of wells or underground structures falling under section 1.1.1.0 of the “Water” classification (IOTA).

Article 83 of Law No. 2023-175 of March 10, 2023, on the Acceleration of Renewable Energy Production (APER), extended this certification requirement to all services involving surveying or drilling, the construction of wells or underground structures not intended for domestic use, for the purposes of monitoring monitoring, or extraction of groundwater, as well as restoration work carried out upon the cessation of operations at such structures, as enshrined in the Environmental Code by a decree of September 2025.

Two decrees published on March 18, 2026, clarified this new regulatory framework and, in doing so, repealed the decree of September 11, 2003, effective December 31, 2027, while incorporating and supplementing its original provisions.

One concerns the construction work itself, as well as the rules governing the operation and decommissioning of these structures; the other concerns the certification requirements for contractors.

Which structures are now affected?

✔ Purpose of the drilling operations in question	✖ Excluded drilling locations
Tablecloth folding Surveys conducted as part of the search for water Groundwater withdrawals, whether temporary or permanent, including those necessary for the operation of classified facilities (ICPE) and basic nuclear facilities (INB) Remediation of contaminated sites and soils through groundwater pumping and treatment Measurement, even temporary, of the water table level or groundwater quality parameters (piezometers, etc.), or in-situ hydraulic tests on the aquifer, particularly in the context of geotechnical or environmental investigations, as well as for the monitoring of facilities classified as ICPEs Assessment and Monitoring of Groundwater at Potentially Contaminated Sites and Soils	Geotechnical or environmental investigations, or the assessment and monitoring of contaminated sites and soils, other than drilling or boring intended to measure the water table level or groundwater quality parameters, or to conduct in-situ hydraulic tests on the groundwater. (For example, drilling intended solely for the collection of soil or rock samples or for the collection of soil gas samples) Exploration or development of geothermal resources, or mining exploration or development Underground storage of gas, hydrocarbons, and chemicals, which are subject to other regulations Remediation of contaminated sites and soils, excluding remediation projects involving groundwater pumping and treatment

✔

Purpose of the drilling operations in question

✖

Excluded drilling locations

Tablecloth folding
Surveys conducted as part of the search for water
Groundwater withdrawals, whether temporary or permanent, including those necessary for the operation of classified facilities (ICPE) and basic nuclear facilities (INB)
Remediation of contaminated sites and soils through groundwater pumping and treatment
Measurement, even temporary, of the water table level or groundwater quality parameters (piezometers, etc.), or in-situ hydraulic tests on the aquifer, particularly in the context of geotechnical or environmental investigations, as well as for the monitoring of facilities classified as ICPEs
Assessment and Monitoring of Groundwater at Potentially Contaminated Sites and Soils

Geotechnical or environmental investigations, or the assessment and monitoring of contaminated sites and soils, other than drilling or boring intended to measure the water table level or groundwater quality parameters, or to conduct in-situ hydraulic tests on the groundwater.

(For example, drilling intended solely for the collection of soil or rock samples or for the collection of soil gas samples)
Exploration or development of geothermal resources, or mining exploration or development
Underground storage of gas, hydrocarbons, and chemicals, which are subject to other regulations
Remediation of contaminated sites and soils, excluding remediation projects involving groundwater pumping and treatment

What are your obligations as a building owner?

If you are planning to conduct surveying, drilling, or the construction of wells or underground structures not intended for domestic use, you must:

*Effective December 31, 2027* Hire a drilling company that holds the appropriate "CertiForage" certification.
There are three levels, ranging from the most comprehensive to the most specific: "All Water Drilling, " "Contaminated Sites and Soils, " and "Piezometers." Note that the “groundwater module” certification held by shallow geothermal companies—referred to as “minimal significance”—is equivalent to certification under the “All Water Drilling” module.
‍
Carry out or arrange for the administrative procedures required for the construction and operation of the facility in accordance with the Regulations on Installations, Structures, Works, and Activities (IOTA) and anti-damage regulations (notification of works – DT), or in the event of modifications or changes in the use of the well (examples: submit a Water Act declaration to the water police or the prefect for ICPEs, register the extraction/monitoring structure with the BRGM Subsurface Database, which will assign it a national BSS identifier, consult the One-Stop Shop in the case of structures located outside property boundaries or near underground networks outside the site...).
‍
Report to the prefect and the mayor as soon as possible any incident or accident that could adversely affect the quality of groundwater and soil, as well as any evidence of groundwater or soil contamination discovered during construction of the project.
‍
Ensure that the drilling company complies with general site setup regulations (including adherence to safety distances) and the requirements established for drilling techniques and equipment, as well as inspections (site management, selection of materials and equipment, cementing, installation and securing of the wellhead, and test pumping for sampling wells). *New rules are introduced by the decrees of March 18, 2026, and apply as of December 31, 2027; compliance with the provisions of standards NF X10-999 or NF X31-614 is presumed to satisfy these rules*
‍
Request that the drilling company provide the final report containing all required information and documents.
‍
Submit this report to the prefect within two months of the completion of the work (three months from December 31, 2027), and upload a copy to the dedicated digital application (not currently available).

While operating your existing boreholes, wells, or underground structures not intended for domestic use, you must:

Develop and implement a maintenance program for wells and wellhead equipment.
‍
In the specific case of wells located within the protection zones of water catchments intended for human consumption—structures that intersect multiple superimposed aquifers—schedule a periodic inspection every 10 years (with the corresponding report submitted to the prefect).
‍
Notify the prefect of any changes to the well’s technical specifications (depth, casing), which may be accompanied by a request to modify the applicable requirements.
‍
Report to the prefect as soon as possible any incident or accident that could adversely affect the quality of groundwater and soil, as well as any evidence of groundwater or soil contamination discovered during the operation of the facility.

When a structure associated with backfilling work reaches the end of its service life, you must:

*Effective December 31, 2027* Use a drilling company that holds the appropriate "CertiForage" certification .
‍
Fill these boreholes using appropriate techniques. *New regulations take effect on December 31, 2027; compliance with the provisions of standards NF X10-999 or NF X31-614 is presumed to satisfy these regulations*
‍
Submit the final project report to the prefect within two months of completion, including all required information (except for boreholes drilled as part of exploratory work that are not retained as piezometers or sampling wells),
‍

*Effective December 31, 2027* Retain the following documents for up to 5 years after the backfilling declaration: Final completion report; Basement Bank Code (BSS) for the structure; Results of monitoring and maintenance activities performed; Records of incidents that occurred.

Revision of the rules governing the creation, operation, and backfilling of test pits, boreholes, and piezometers

Regulatory Context

Which structures are now affected?

What are your obligations as a building owner?

To find out more :