Hn the Alpujarra, on the slopes of the majestic Sierra Nevada in Andalusia, the silence is broken only by the sound of a stream flowing through the snow. Except it’s not a stream but a acequiapart of a network of thousands of kilometers of irrigation canals created by Muslim peasants over a thousand years ago.
The canal begins at an elevation of 1,800 meters (5,900 ft) and, fed by melting snow, for centuries provided water to the village of Cáñar and beyond until it fell into disuse in the 1980s due to the progressive depopulation of the region.
Today, it comes to life thanks to a project designed by the Biocultural Archeology Laboratory of the University of Granada and supported by local and European funding. With the help of volunteers, the MemoLab project is restoring the region’s extraordinary hydrological network at a time when the climate crisis is exposing Spain to prolonged periods of drought and intensive agriculture is putting extreme pressure on supplies in water.
When the Arabs and Berbers colonized Spain in the early 8th century, they brought water conservation techniques acquired over centuries to the Middle East. “The Islamic agricultural revolution was the first green revolution. They brought together techniques and knowledge about water, soil, plants and also about the behavior of snow,” explains José María Martín Civantos, professor of archeology at the university and driving force behind the project. “They have transformed the way water is used in the Mediterranean.”
Techniques introduced by the Muslims allowed for greater agricultural diversity, with crops such as sugar cane and citrus fruits being introduced.
“Involving people in creating these irrigation systems was a way to assimilate the existing population, who could see the benefits,” adds Civantos.
Rain comes to the Mediterranean in brief torrential bursts, with the result that most of the water is lost as it flows into rivers and the sea. The genius of the acequia system is that by controlling the flow of the water, whether it comes from rain or snowmelt, it reduces runoff, while allowing water to be absorbed from the ground to replenish aquifers in what is literally a trickle-down effect .
Civantos describes this as “sowing water”. Rather than diverting water to specific crops, the idea is to “soak the mountain” so water can be stored in aquifers for use in times of drought.
“The basic condition for the system to work is that the channel is not too permeable and has a slope that maintains the right water flow. Then you need a community of people to maintain it,” says Sergio Martos-Rosillo, a geologist involved in the project.
“The system is efficient, the aquifers are being replenished and no technology is needed,” he says, adding that the revival of similar techniques is being studied in several Latin American countries, including Peru, and that the California is also interested in modern irrigation techniques. have become unsustainable.
The system in Spain “has been in use for over 1,000 years, proving its adaptability,” says Martos-Rosillo. “It’s much more manageable and adaptable than building a dam and much more resilient to climate change.”
Cayetano Álvarez, president of the community of irrigators of Cáñar, has no doubts about the impact the project has had on the village. “Everyone is obliged to maintain the canals on their land,” he says. “This project has made a big difference, but there are abandoned acequias in many other villages nearby.”
The system is integrated and if the land is abandoned and the channels become blocked, water cannot flow past the blockage. Thus, each spring, the university and the villages organize groups of volunteers to clear the obstructions of the acequias.
“It’s not just about removing leaves and mud. We also consult local people on how to lay the pieces of slate that line the acequias,says José Antonio Palma García, a volunteer for five years.
“I feel good doing this job. I feel like I’m giving something back to the earth. I also meet people I would never normally meet – we are like one big family.
Across the sierra is the village of Alfacar above Granada, near where the fascists are widely believed to have murdered the poet Federico García Lorca at the start of the civil war in 1936. It is also the site of a brick-walled pool of clear mountain water known as the Tear Spring.
“It is so called because of its shape”, explains Elena Correa Jiménez, researcher on the project. “The spring is fed by an aquifer and the acequia was created 1,100 years ago to supply water to the Albaicín, the medina of Granada, 8 km [five miles] a way.”
MemoLab has restored much of the acequia and, although it does not reach Albaicín, it now irrigates the university gardens.
Civantos says one of the challenges of the project was trying to recover collective knowledge that has never been written down. Due to the Catholic reconquest of Islamic Spain and the expulsion of the Muslim population in the early 17th century, much of this knowledge was lost.
“People don’t think peasants could design anything that complex,” Civantos says. “The Romans built aqueducts and other aqueducts but it was always for the glory of the state. This work was done so that ordinary people could survive.
“The recovery of this system implies the recognition of an important part of our heritage. Muslim Spain was above all an agrarian society.
“You cannot understand the glory of Cordoba or Granada without understanding that what is behind it is the wealth created by a form of agriculture that is much more advanced and productive than elsewhere in Europe.”