Only the pipeline entering the heavily protected tunnel gives any indication of what to expect. But a 350-metre drive through the heart of the Grand Rochefort mountain soon reveals why it is walled off to the public. For as you exit, you are treated to a vast clearing and lush green water-refreshed pastures as far as the eye can see.
“Visitors are always surprised, all of a sudden you have the impression that you’re at the end of the world,” says the director of the Rochefort water catchment station, Jean-Louis Avrillier, as he smiles. “You would never imagine that so close to Grenoble.”
Grenoble, the capital of Isère, a department in the southeast of France, guards its secret well: the water that runs through the taps of the city is managed by the public sector — and is amongst the cheapest in France. The city, located around 10 km north of the catchment station, stretches across 2,400 hectares and has yet to be perturbed by urbanisation.
Water Doesn’t Just Fall From the Sky
The Rochefort water catchment station, a haven of peace is well-protected and with reason: the water tables hidden beneath the swaying tall grass are invaluable. Since the end of the nineteenth century, it has supported the 758,000-strong population of Grenoble and its metropolitan area with pure and untreated water — a unique case today in France for such a big city.
The secret behind such a feat? The layer of clay, a geological characteristic of this zone, is a more efficient filter than chlorine or any other chemical product used to render water drinkable.
Even Napoléon, ahead of his time, had homed in on the potential of this site, imagining the neighbouring metropolis as a thermal spa resort. Here, at the doorway to the Alps and at the foot of the Vercors Massif and the Chartreuse range, the water isn’t simply excellent, it is also abundant.
“The volume collected corresponds to only 17% of its total capacity,” explains Avrillier, who manages 42 employees at the site. Since 1885, when the…