France: Industry at the forefront of water reuse

With pressure on resources increasing, the French industrial sector is increasingly committed to reusing internal wastewater to reduce its consumption of fresh water and secure its processes.

Industry accounts for around 10% of water consumption in France, with a variety of uses: cooling, cleaning, manufacturing, cutting, dilution, etc. However, a significant proportion of this water does not need to be of drinking quality. Reuse of treated wastewater therefore helps to optimize consumption by setting up closed or semi-closed circuits.

Some companies, particularly in the agri-food, chemical, and metallurgy sectors, are investing in on-site treatment units: physical-chemical, ultrafiltration, nanofiltration, UV disinfection, etc. Once treated, the water is reused in production circuits, for cleaning lines, or even feeding cooling towers.

In addition to its environmental benefits, Reuse of treated wastewater offers an economic advantage. Reducing water withdrawal volumes lowers fees, treatment costs, and the uncertainty associated with prefectural restrictions in the event of drought. Many sites achieve a return on investment within 3 to 5 years.

Concrete example: a metal cutting factory in eastern France has set up a physical-chemical treatment plant that reuses 80% of its process water. Result: 25,000 m³ saved each year, with costs recouped in less than 4 years.

The Water Agency, ADEME, and certain regions offer investment assistance for this type of project. Industrial Reuse of treated wastewater thus becomes a strategic lever for combining sobriety, performance, and resilience.