In 2023, hundreds of voters participated in a participatory analysis mission whose objective used to be to map water high quality at the territory of France. An method that teaches researchers so much and raises consciousness amongst volunteers.
On September 29, 2023, throughout France, hundreds of other folks took at the function of researchers for the weekend. Armed with their smartphone, coloured tape and a sheet of directions, they launched into a singular collective revel in: measuring water high quality in France in rivers, fountains, lakes, wells and puddles. In only some days, virtually 800 samples had been accumulated and greater than 20,000 knowledge had been measured.
Location of measurements performed throughout the Grande Sinchr’Eau. Los angeles Grande Sincr’Eau, supplied by way of the creator
In the back of those spectacular figures lies a human and clinical journey: the Grande Sinchr’Eau, an enormous participatory clinical initiative awarded some of the 2025 CNRS mediation medals for its originality and affect on society. This distinctive participatory revel in printed the chemical range of French waters.
The primary is inconspicuous: dip the strip in water, practice the colour of the pellets, after which evaluate them with the dimensions. This gesture, each easy and amusing, in truth hides precious measurements: pH (or acidity), the focus of nitrates from fertilizers, chlorine, in addition to heavy metals equivalent to copper or lead. For lots of, this revel in reasons a “wow” impact: “We felt like we were playing, but in fact we were doing real science,” mentioned a mom who got here to reside the revel in together with her daughter. That is the energy of citizen science: enabling everybody to take part in analysis whilst generating knowledge helpful to scientists.
Electorate of every age at paintings: measuring, watching and figuring out water throughout France. Los angeles Grande Sinchr’Eau, Equipped by way of the creator Mosaic of native truth
The effects, compiled by way of groups from INSA Toulouse and the Toulouse Biotechnology Institute, expose a France stuffed with contrasts. In Brittany and the Massif Central, the water is extra acidic, because of the granite and volcanic soil, as a result of those rocks comprise few minerals able to “buffering” the acidity. Rainwater, naturally moderately acidic, is subsequently now not neutralized by way of passing over those terrains, not like in limestone areas the place the rocks free up carbonate that raises the pH. Within the agricultural plains of Beauce and Champagne, nitrates on occasion exceed 100 mg/L, which is direct proof of in depth fertilizer use.
Different indicators are showing within the town: in Lyon, Toulouse or Marseille, voters have detected copper as much as 6 mg/L, a degree thrice upper than the prohibit of consuming water high quality (2 mg/L), principally associated with the corrosion of previous copper pipes. In sure rural spaces, chlorine is nearly absent, whilst in Ile-de-France or Rhône the focus reaches ranges ten instances upper than the ones noticed within the nation-state of the Massif Central. This stays appropriate with requirements, however displays a lot more pronounced disinfection of enormous city networks, on occasion explaining the chlorinated water tastes reported by way of sure customers.
In different phrases, there’s no unmarried French water, however a mosaic of native waters, every bearing the hallmarks of its soil, use and infrastructure.
Chlorinated puddles and iron wells
Some of the samples, some waters in reality stand out. If, at the complete, the pH stays inside standard values (between 6 and seven.6), the chemical range is sudden. General chlorine, because of this each loose chlorine (the lively disinfectant) and mixed chlorine (which has already reacted with different ingredients), on occasion reaches 10 mg/L, or 5 instances the focus in a public pool.
Some city puddles seem to have been by chance sanitized: runoff from sidewalks, residues from family merchandise, floor washing. Briefly, if the water within the puddles isn’t drinkable, some are strangely neatly disinfected!
The water of France at a look: six citizen maps that expose the chemical range of the territory. Los angeles Grande Sinchr’Eau, supplied by way of the creator
Some wells wreck all data for iron, with concentrations as much as 25 mg/L, or 500 instances the consuming prohibit. At this level, the water takes on an orange hue and a powerful steel style. Out of one thousand samples taken, 8.4% of the water used to be rated brown by way of the voters, which is an indication of intense iron oxidation in native watersheds. This phenomenon, commonplace in sure rural spaces, isn’t unhealthy in itself, however it makes the water unusable and may end up in deposits, stains and clogging of family installations. It illustrates the prime chemical variability of native waters and the demanding situations explicit to untreated wells.
Every other discovery: ammonium, provide at as much as 40 mg/L in sure samples. This compound, created by way of the decomposition of natural subject or agricultural runoff, displays intense organic job: briefly, very alive water, however now not essentially the type we wish to drink.
Water, the reflect of our existence
In the back of the anecdotes and figures, those citizen measures inform a easy fact: water data our way of life. It circulates, transmits and recollects our actions. In towns, it incorporates chlorine, copper and family waste. Within the nation-state, it carries nitrates, ammonium or iron. And in herbal spaces, it steadily stays extra balanced, however by no means totally freed from human imprint.
Along with maps, Grande Sinchr’Eau attracts a curious and tasty France. A survey of 120 members finds an intergenerational mobilization: 22% are below 18 years previous, 21% are between 46 and 55 years previous, and 45 number one and secondary faculty categories participated within the revel in. The motivations are other: 54% see it in an effort to give protection to the surroundings, 43% to give a contribution to analyze, 28% to be informed and 25% out of interest. In different phrases, dimension turns into a method of figuring out and motion.
Unfavorable analysis whilst elevating the attention of voters
The consequences of the method on volunteers are spectacular: 81% of members imagine that the revel in modified their perspectives or conduct, and 82% really feel that they’re taking part in environmental coverage. When requested what phrases they suspect describe water, those that arise maximum are lifestyles, important and valuable, reflecting a delicate, virtually emotional courting with this shared useful resource.
After all, to the query “Who should act to save water?” », 83% point out the state, 79% scientists, 71% associations and 54%… themselves. Science is now not perceived as a reserved area: it turns into a shared house, the place wisdom is constructed in combination and the place everybody assumes their social accountability.
After all, are we able to drink water from a puddle? No, as a result of on occasion they comprise extra chlorine than within the pool. However we will be able to at all times practice, measure and evaluate them. Those experiments remind us that there’s no want for a laboratory to do science: just a little interest, a coloured tape and a want to grasp are sufficient to reach at collective wisdom. The Nice Sinchr’Eau is evidence of that: science can spring up anyplace, even from an extraordinary puddle.
