Treating toilet water for drinking is not futuristic (France is lagging behind)

WATER – In France, 20% of our drinking water ends up in our toilets. This waste is becoming absurd as the lack of water is felt throughout France. And it is unfortunately not the storms, however violent, of the last few days that will be enough to compensate for the cumulative water deficit in 2022. Hence the call at the beginning of August from the European Commission urging Member States to reuse their wastewater.

The principle is simple, once the water is used in the habitats, it will be collected and then treated in treatment plants in order to be reinjected into the drinking water circuit. Usually it is discharged into waterways.

A “regrettable” loss of fresh water for Julie Mendret, researcher at the European Institute of Membranes. The specialist in the reuse of treated wastewater (REUT) explains to the HuffPost that this recycled water can be used for many other uses “such as agricultural irrigation, road cleaning, firefighting, or golf course watering”.

A natural fertilizer

On paper, this solution seems crystal clear, but that’s without taking into account the administrative burden that surrounds the procedure. “In Europe, it is very restrictive and changes are very slow”, comments Julie Mendret who is campaigning for at least non-potable treated wastewater to be used for agricultural irrigation. On this point, in May 2020, Parliament adopted framework regulations which set minimum quality requirements.

Four quality classes are defined by the regulations. For crops eaten raw, such as tomatoes, for example, water quality rated A is required, while a D is sufficient for watering a place that does not receive visitors. The stated objective of Europe with this harmonization of practices is to “quadruple the reuse of wastewater by 2025, to reach 6.6 billion cubic meters”.

And for good reason, wastewater treatment is overflowing with advantages, in particular to reduce the use of fertilizers on crops: “The effluent leaving the treatment plant contains fertilizing elements (nitrogen, potassium, phosphorus)”, explains the researcher. In a 2010 report, the Food and Agriculture Organization of the United Nations (FAO) estimated that this would save 30% of nitrogen fertilizers and 15% of phosphate fertilizers.

An effect “yuck”

The problem, let’s say it, is that France is totally picking up on the treatment of this waste water. Only 0.3% of drinking water is reprocessed, which ranks it far behind Italy and Spain, which use between 8 and 14% of their treated wastewater, and very far behind Israel with 80%, according to the Water Information Center. But even if France made considerable efforts to develop the practice, nothing says that the citizens would approve.

An effect “yuck” is felt by many French people who are rather reluctant to the idea that the water they use every day waters the fruits and vegetables they will then eat. According to Julie Mendret, it is because of a confusion between the “reuse of treated wastewater” and “spreading raw water”i.e. which has not gone through a sewage treatment plant. “It was done years ago and there yes, there were epidemics of cholera and gastroenteritis. But the reuse of treated wastewater that we are talking about today is highly regulated. »

The researcher not only dismisses any danger to health but explains that we could even go further and develop the technique of “direct potabilization” to drink water “treated used” eyes closed.

In Singapore, we already drink “treated waste” water

Singapore is a pioneer in the field. Using state-of-the-art water treatment technologies, the city-state has created “new water”, the “NEWater”which has become an emblem of its ability to recycle water. ” Five factories now produce 430 million liters per year, meeting a third of Singapore’s water needs”reports the newspaper The echoes.

For now, this water is mainly intended for the electronics industry, which needs water of high purity. But 5% of this water is returned suitable for consumption, according to the criteria required by the World Health Organization. Singapore’s national water agency even launched its “NewBrew” in the spring, a beer brewed from ultra-filtered wastewater.

French researchers are watching these innovations with great interest. We are far from Singapore but an experiment is born in Vendée. Work on the “Jourdain project” has already got off to a good start and first tests should be carried out from 2024.

Part of the water from the Sables d’Olonne wastewater treatment plant will be recovered and treated in order to be reinjected into the drinking water circuits, details France Info who questioned Jacky Dallet, president of the Vendée Water Syndicate. This is the first time in Europe that water will be reused for domestic use.

Filtered and disinfected, the water will no longer contain micropollutants or toxic substances. Quite drinkable, the CEO of Veolia Antoine Frérot, even promises “water probably much cleaner than river water”. There remains only the psychological barrier to cross.

See also on The HuffPost: Faced with drought in Switzerland, water delivered by helicopters to breeders

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