The summer of 2022 has seen unprecedented droughts that have ravaged crops, threatening the livelihoods of millions across the world. France wasn't spared, with almost all departments facing water restrictions. Increasingly, farmers are turning to water reservoirs, a method decried by environmentalists. In this episode of Down to Earth we travel to western France, where tensions are mounting over the management of water supplies.
Sharing a precious resource, now scarcer than ever
In the Deux-Sèvres department of western France, a large water reservoir stands out against corn fields nearby. This artificial pool, with a capacity of 260 000 m3, is one of 1,000 projects currently underway in France. It works by collecting and storing rainwater that naturally infiltrates the subsoil in winter, providing a stable supply of water for farmers to use in spring and summer.
These reservoirs may seem like the ideal solution to salvage crops from recurrent droughts, especially as the surface area of French cultivated land that needs to be irrigated has gone up by 15 percent in the last decade. But what originated as a smart hack is turning out to be an environmental disaster. Activists in the area have condemned what they have described as a "water grab" to the detriment of an entire ecosystem.
'Not a case of water hoarding'
Five farming businesses are connected to the reservoir, including a goat farm run by two brothers, Samuel and Basile. They say that if it wasn't for the reservoir, their alfalfa production to feed their animals would have been compromised. "It's not a case of water hoarding," explains François Petorin, the president of the local water cooperative, adding their activities are strictly regulated by the government dictating the quantity of water that can be extracted.
'Over-irrigation' and civil disobedience
Julien Leguet, the spokesperson of the citizens' group "Basins, no thank you!" is adamant that the so-called mega-reservoirs amount to a water grab. The non-profit sees a clear link between rivers drying up and the construction of water reservoirs.
"The great failing in our country today is that we are stealing an entire territory, an entire ecosystem's water, for the benefit of a few," says Leguet.
One of the main criticisms of reservoirs is the evaporation that takes place once groundwater has been left out in the open. This can reach up to 50 percent, according to the non-profit.
The collective has been putting up a fierce fight against the reservoirs, with the group recently deciding to act using civil disobedience.
"We have given the state an ultimatum," warns Leguet. "If any basin work starts in the next few weeks or months, thousands of us will protest."
Harvesting every last drop of water
The agricultural sector already uses up almost half of France's freshwater reserves. With drought exposing more and more regions to water shortages, saving this precious resource is also becoming a priority for farmers.
Alexandre Grenot grows corn and other cereals in western France. He has recently installed a drip irrigation system allowing him to drastically reduce his consumption of water.
"Drip irrigation means 50 percent less water consumption and reducing the electricity bill by at least two-thirds," Grenot explains.
In practical terms, it's a central pipeline that serves smaller pipes, with little ducts every two rows. On these black ducts, there is a hole every 40 centimetres. This allows water to drip directly onto the ground, at root level.
The technology is far from new but high costs have put a break on its development. According to Grenot, it costs €300 to run per hectare, not counting the workforce required for maintenance.
Wastewater reuse: A new frontier for irrigation?
Others are considering a different alternative: reusing wastewater. Currently, in France, less than 1 to 2 percent of wastewater from homes, toilets or washing machines is repurposed for agriculture.
Its potential has been largely overlooked, says Nassim Ait Mouheb, a researcher at INRAE, France's public research institute on agricultural science.
He oversees a scientific experiment in southern France, a region that regularly suffers from high heat and drought, using wastewater to irrigate vineyards. The water has been properly cleaned up in a treatment centre before being sprayed onto the fields, but questions remain. Will grapes grow normally? Will it have an effect on the soil? And above all, is it safe for the consumer?
Other countries such as Tunisia, Spain and Italy are reusing between 10 and 25 percent of their wastewater. But Ait Mouheb insists it's not a miracle solution: "Treated wastewater is a part of the solution but we need to think about wider change."
