In France, tap water is the most monitored and controlled food. Every day, every French person consumes this resource that is essential to life, without always knowing where it comes from or how it is controlled. As revealed by France Bleu and the investigation unit of Radio France this Thursday, The presence of “eternal pollutants” (PFAS) in excessive quantities was found in tap water during a series of tests carried out at the same time throughout the country.
How is water controlled? How is it treated to make it drinkable? Who is responsible for these controls? And who makes the decisions regarding quality standards? France Bleu explains what you need to know about tap water control.
The big and small water cycle
To fully understand the issues surrounding water, we must first go back to the basics of the water cycle. There are the great cyclea complex natural process that includes evaporation, cloud formation, precipitation, runoff, and infiltration of water into the ground.
It is to be put in parallel with the small water cyclea system designed by man to manage water used primarily for domestic and industrial purposes. This cycle begins with the collection of raw water from nature, its treatment to make it drinkable, its distribution to consumers and then the collection of wastewater, treated and then discharged into the environment.
For effective water management, managers must therefore take these two cycles into account.
Where does the water that comes out of the tap come from?
Drinking water comes mainly from two sources: groundwater and surface water (rivers, lakes). According to the Water Information Center, Around 62% of the water distributed in France comes from groundwater, and the remaining 38% from rivers and reservoirs.
According to the latest available summary on water quality in France dated 2022, there are 32,900 catchments, 16,900 drinking water production stations and 23,900 distribution networks in France.
The French consume an average of 149 liters of drinking water per day.of which around 7% is for food and drink and 93% for hygiene.
The stages of water treatment
Depending on where the water is taken from the natural environment, it can be more or less clean. Groundwater benefits from the natural filtration of the soil and is much cleaner than surface water.
Depending on the quality of the raw water, a whole series of treatments are carried out: decantation, filtration, disinfection. The aim is to rid the water of micro-organisms that may be of biological or chemical origin.
The water is first filtered through increasingly fine screens to remove the largest unwanted elements. In order to collect the smallest elements, a method can be used that aims to coagulate the small particles to form larger and therefore easier to recover elements. The water is then filtered and chemically treated with chlorine or ozone.
Once this series of treatments has been carried out, the water is stored in reservoirs before being distributed through the pipes to consumers.
The various checks carried out
In France, the control of drinking water is governed by the Public Health Code and supervised by the Regional Health Agency (ARS). This agency, in collaboration with local authorities and water managers (often companies such as Veolia or Suez), sets up a rigorous control plan. Monitoring is carried out by those responsible for production and distribution facilities. The ARS is responsible for implementing health control.
In 2022, 325,000 samples and more than 18 million analyses will be carried out in Francesays the Ministry of Health. The frequency of checks is based on the flow rate of the installations and the number of people supplied. Some installations are checked once every ten years, while others are checked several times a month.
• At the collection point: samples are taken regularly to check the quality of the raw water, i.e. before any treatment.
• At the outlet of the treatment plant: we check here that the treated water complies with the standards set by the regulations.
• In the distribution network: samples are taken directly from consumers’ taps to ensure that the quality of the water is maintained throughout its delivery.
These checks cover several criteria, both microbiological (presence of bacteria), physicochemical (pH, nitrate, pesticide and PFAS content) and organoleptic (taste, odor).
What standards?
The quality of drinking water is subject to very strict standards, mainly defined by European Directive 2020/2184It sets maximum values for various microbiological and chemical substances (nitrates, heavy metals, chlorinated solvents, pesticides, etc.). The directive therefore requires continuous monitoring of the entire production process.
The three main risks regarding drinking water are microbiological contamination (such as Escherichia coli, fecal matter, etc.), chemical risk (arsenic, fluorides, nitrates, etc.) and contaminants such as pesticides, pharmaceuticals or microplastics.
For each substance, a maximum limit is set based on the health risks in the more or less long term.
PFAS controlled from 2026
From 2026, PFAS will be integrated into regulatory health monitoring programs for water intended for human consumption, according to a European directive. This monitoring is already being implemented “gradually in place”, assures the General Directorate of Health. The future quality thresholds of these “eternal pollutants” have thus been integrated into the French regulatory framework from 2023, in the event of anticipated research set up according to local contexts and detection. Some ARS and communities have already started to carry out checks.
As shown by the investigation conducted by France Bleu and the investigation unit of Radio France, 43% of the 89 samples taken throughout France revealed the presence of PFAS. 27 samples contained PFAS banned or classified as carcinogenic, including five at worrying levels.
Currently, a quality limit of 100 nanograms per liter has been set for the sum of twenty PFAS. But other European countries have chosen to be much more protective of the health of populations. In Denmark, for example, this threshold is 2 nanograms per liter for the sum of four PFAS. Outside the European Union, other countries go even further and control 25 different PFAS instead of 20.
In France, systematic screening for PFAS in drinking water will be integrated into the health monitoring carried out by the ARS from January 1, 2026.
Overall good quality
The most controlled food in France, tap water is generally of very good quality in our country. According to the latest synthesis, as of 2022, 98.2% of the French population was supplied with water that permanently complied with the quality criteria concerning microbiological parameters. A proportion that falls to 86.4% of the population with regard to the quality concerning pesticides, and 98.8% concerning nitrates.
What happens in case of non-compliance?
When an analysis reveals a non-compliance, the health authorities must act quickly. It is mainly the Regional Health Agency (ARS) that is responsible for assessing the risks incurred by the population. This can result in recommendations such as boiling water before consumption, or, in the most serious cases, temporarily stopping the distribution of drinking water. Corrective measures are then put in place, whether it is an adjustment of the treatment or an in-depth search for the source of pollution.
Temporary exemptions may be granted by the prefect if exceeding a standard does not pose a danger to the public health of the populations concerned. The same applies if it is not possible to act quickly without being able to maintain distribution. These exemptions are granted in return for an action plan detailing the measures that must be taken to correct the problem. An exemption may not exceed three years, renewable twice.
How to know the quality of your tap water?
Consumers can consult the quality of the water in their municipality via the ARS reports, available online or posted at the town hall. In addition, each year, water bills must contain precise information on the quality of the water distributed locally.