In response to the contamination of drinking water by PFAS and pesticides, the inter-inspectorate task force is assessing the scale of the potential costs and proposing a phased, region-specific action strategy. This strategy combines preventive and remedial measures to ensure the protection of the public. It relies on greater involvement by the main emitters of PFAS and pesticides in the costs of decontamination, in order to limit the inevitable rise in water prices.

In 2024, just over 29 per cent of the French population was exposed, in water intended for human consumption, to pesticides or per- and polyfluoroalkyl substances (PFAS) – man-made chemical pollutants – at concentrations exceeding European quality limits.

Situations requiring restrictions on tap water consumption for health reasons remain rare. However, the difficulty in measuring all forms of pollution, the persistent nature and continued use of certain molecules, as well as the expanding scope of substances detected or regulated, give rise to concerns about an increase in drinking water non-compliance in the coming years.

A cause for concern for public health

This situation is a cause for concern for public health (chronic exposure and ‘cocktail’ effects). In addition to the direct impact of pollution on people, it undermines access to water (closure of water abstraction points) and places a strain, on the one hand, on public finances and, on the other, on public confidence in drinking water.

Having consulted over 300 people representing all the interests at stake – in particular local elected representatives and residents of areas affected by significant pollution, as well as consumer and environmental protection organisations and professionals in the water management sector – the task force based its conclusions on extensive data analysis and an in-depth international benchmarking exercise. It therefore sought to formulate context-specific findings and realistic, proportionate proposals.

Historical pollution requiring new investment

The vast majority of current instances where drinking water quality limits are exceeded stem from the past use of pollutants that are now banned. Reducing emissions at source and strengthening the protection of water catchments – which remain essential for safeguarding the future – will not be sufficient to resolve these situations or restore compliance with drinking water quality standards in the short term. New interconnections and water treatment plants will need to be built to tackle, in particular, this historical pollution.

The task force notes, however, the great difficulty local authorities face in making the necessary investments. Whilst responsible for water quality, they most often lack the critical mass required to secure the necessary funding.

A national strategy to anticipate, assess and take action

Anticipating the growing need for pollution remediation, driven by both the accumulation of pollutants and the tightening of the regulatory framework, the task force recommends capitalising on the complementary nature of the available measures: reducing emissions at source, comprehensive protection of water resources, securing and reclaiming water abstraction points, pooling or substituting water resources, and targeted treatment where circumstances warrant it.

The national strategy for anticipation, assessment and intervention, devised by the task force to enable earlier intervention and to guide local authorities’ decisions according to the nature of the pollution and the local situation, aims to coordinate these actions more effectively. This must be accompanied by increased support from water agencies to local authorities regarding drinking water, investment planning defined at the river basin level, and better coordination between health and environmental policies.

Four scenarios: high and unavoidable costs

Drawing on lessons from the first cost assessments carried out in Europe and France, the report proposes four scenarios for pollution remediation, each involving an increasingly broader scope of intervention.

In all cases, the costs will be high, with potential additional costs ranging from €1.3 to €5.7 billion per year by 2026 to fund decontamination – all the more so given that, at the same time, numerous facilities will need to be replaced and wastewater management systems upgraded.

Funding decontamination without penalising vulnerable households

The report proposes, first and foremost, to strengthen funding mechanisms based on the ‘polluter pays’ principle (extending the PFAS levy and the levy on diffuse agricultural pollution, and reforming taxation linked to the water cycle), but this will not be sufficient. It will also be necessary for local authorities to pool their resources to meet investment needs and secure long-term loans.

However, an increase in the price of water will remain unavoidable. To cushion the impact, the task force proposes regional solidarity schemes targeted at the services most at risk, as well as social support measures for the most vulnerable households.

Taking action upstream, on emissions at source

As a complementary approach to the interministerial plan on PFAS, agricultural transition policies and the food security and environmental health measures already underway – and looking beyond the issue of drinking water, which represents only a limited part of the human exposome* – the report emphasises the need to reduce emissions of both PFAS and pesticides at source.

European initiatives to ban the production and use of these products or to impose regulatory limits on emissions must be supported as far as possible, as must all measures designed to prevent the release of these substances into the environment: the search for alternatives, regulating the use of products in certain areas or near vulnerable populations, improving filtration technologies, and eliminating environmental discharges throughout the products’ life cycle.

Whilst this transition will entail significant adaptation costs for economic actors, it represents an essential investment in better protecting public health and the environment, as well as in limiting future clean-up costs, which will be difficult to sustain without a major prevention effort starting now.

* The exposome is defined as the totality of exposures to pollutants that an individual faces over the course of their life.