• Welcome
  • News
  • The quality of drinking water, a crucial subject
Qualité de l'eau potable
pedagogy
3 April 2025

The quality of drinking water, a crucial subject

Guaranteeing high-quality drinking water is essential to protect public health and the environment. This challenge is based on precise criteria, rigorous standards and innovative solutions. Let’s explore the different aspects of drinking water quality and how to maintain it.

What are the quality standards for drinking water?

The strict quality criteria for drinking water are set by bodies such as the World Health Organization (WHO) and adapted by national legislation. In Europe, Directive 98/83/EC requires more than 50 chemical and biological parameters to be monitored. In France, the regional health agencies (ARS) carry out thousands of analyses every year.

For water to be considered fit for drinking, it must:

  • Be visually clear, with no abnormal colouring.
  • Not give off any unusual odours or have any unusual tastes.
  • Comply with strict thresholds for chemical contaminants (heavy metals, pesticides, etc.) and bacteria.

 

Analyse de l'eau potable

Despite the application of these standards, occasional incidents may still occur, calling for constant vigilance and the adoption of modern technologies to monitor networks.

What are the quality criteria for "drinking" water?

The quality of drinking water is assessed on the basis of numerous parameters, which fall into three main categories:

1. Physico-chemical parameters, which relate to the chemical composition and physical characteristics of the water.

  • pH: measures the acidity or alkalinity of water. Drinking water must have a pH of between 6.5 and 8.5 to prevent pipes from corroding and to ensure that it is safe to drink.
  • Residual chlorine: chlorine is added to disinfect the water. A residual chlorine level of between 0.1 and 0.5 mg/L provides sustained protection against pathogens.
  • Electrical conductivity: reflects the concentration of dissolved salts in water. High conductivity may be a sign of contamination by mineral or organic substances.
  • Hardness: measurement of the levels of calcium and magnesium. Water that is too hard causes limescale deposits, while water that is too soft can be corrosive.
  • Nitrates: their presence is often linked to agriculture. Nitrate levels must be below 50 mg/L to avoid health problems, particularly in infants.

2. Microbiological parameters, which ascertain that there are no pathogenic micro-organisms.

  • No bacteria or viruses: drinking water must be free from faecal coliforms, salmonella and other infectious agents.

3. Organoleptic parameters, which guarantee clear, odourless water with no unpleasant taste.

  • Turbidity: cloudy water may indicate the presence of particles in suspension, which could carry contaminants. Turbidity must be less than 1 NTU (Nephelometric Turbidity Unit).

Focus on PFAS: what are eternal pollutants?

PFAS (per- or polyfluoroalkyl substances) are a large family of chemical compounds that are very persistent in the environment. They originate mainly from industry, and their special properties have spurred their use since the 1950s. Above a certain consumption threshold, PFAS can have harmful effects on health, but these are still poorly understood.

Since 2020, France has set a quality limit for 20 PFAS substances and, since 2023, these regulated PFAS must not exceed the limit of 0.1µg per litre of water. The services that distribute drinking water to consumers' taps are required to monitor the water and ensure that it complies with the following standards. From 2026, the regional health agencies (ARS) will be required to analyse PFAS levels in their health checks.

Monitoring using connected devices

Connected devices such as LabFLO sensors deliver an advanced solution to independently monitor a number of parameters. The LabFlo solution is a chlorine and turbidity probe for physico-chemical analysis of drinking water. It is specially designed to help operators monitor the quality of drinking water in distribution networks, so they can attain their health compliance targets.

LabFLO Hydreka

How do you know if the water is pure and of good quality?

Good quality water has satisfactory health and sensory characteristics. There are several ways in which private individuals can check the quality of their water.

How can a resident check the quality of their drinking water at home?

1. Consult the water supplier's annual report: this document gives details of the results of analyses carried out on the local network.

2. Use test kits: these tools can easily be used to measure parameters such as pH, hardness or nitrates.

3. Examine the water: cloudy water or a suspicious odour should alert users, who can contact their supplier for further analysis.

Test de PH

How do you ensure that water is of good quality?

Water management relies on regular interventions and innovative technologies.

1. Maintain the networks: by cleaning the pipes regularly, the proliferation of micro-organisms can be prevented. Solutions such as those offered by Hydreka can be used to monitor the condition of pipes in real time and adapt the actions that need to be taken. Outdated networks are a source of deterioration in quality and of wastage. Renovating them is a priority. This is why proactive infrastructure maintenance is so important from both an economic and an environmental perspective.

2. Protect networks from external pollution: the systematic installation of anti-pollution devices also helps to preserve the quality of drinking water. A good example of this is to use reliable and long-lasting equipment, such as the Sainte-Lizaigne 310 anti-pollution check valve. This device prevents backflow and stops the public distribution network from being polluted by water from a domestic network.

Sainte-Lizaigne Clapet antipollution

3. Real-time monitoring: sensors such as those developed by Claire Connect can measure water quality remotely, thus offering optimum response times in the event of contamination. For example, the NODE, from Hydreka, can be used to monitor drinking water catchment areas with greater precision and ensure that standards are complied with. Connected sensors and automation systems not only improve quality, they also reduce operating costs.

NODE SOLUTION

4. Use connected technologies to control: devices such as Wayve valves can be used to automate purges and regulate critical factors such as VCM (Vinyl Chloride Monomer) levels. Thanks to these technologies, water quality can be kept under control. By installing connected systems, purging can be managed more effectively, by reducing the need for human intervention and preventing water from becoming stagnant. These solutions help to reduce health risks. We can even talk about automating these purging operations with connected valves.

Pilotage par vannes connectées Wayve

5. Raise awareness among users: a better understanding of what is at stake and of responsible practices can boost the sustainability of collective efforts. As a group, we offer innovative and long-lasting solutions to our network operator customers, to help them build and maintain high-quality networks that are designed to withstand the tests of time.

Formation

Technological innovations, allied to appropriate maintenance and precise planning, illustrate how end consumers can benefit from reliable, high-quality drinking water, while preserving natural resources. The ultimate goal of these measures is twofold: to guarantee drinking water that complies with the most stringent standards, while optimising the management of water resources.

Working towards sustainable management of water

Safeguarding water quality is not just a question of monitoring and technology, it also depends on taking a long-term vision of how the resources are managed. Initiatives such as those undertaken by the Claire Group to preserve natural environments show that respectful management of ecosystems can go hand in hand with technological breakthroughs. Real-time monitoring, data transmission and process automation, as described in the Claire Connect solutions, are the foundations of this transition to sustainable management.

Eau potable

Conclusion

The quality of drinking water is a complex but crucial factor, requiring a collective commitment. Innovations such as connected sensors and automated valves can play a decisive role in preserving this precious resource. Protecting water means protecting our health and our future.