Photos: Medieval Irrigation Channels Could Be the Answer to Spanish Droughts

A 1,000-year-old Moorish invention may be the answer to Spain's increasing heat problem.

A chain of over 15,000 miles of acequias throughout the mountainous region of Spain is being restored as a low-cost way to bring water to crops during a time of increasing heat and droughts. Acequias are a network of irrigation canals set up by the Moors that bring snowmelt down from the mountains and distribute it to the land below.

Experts believe that the ancient solution will help spread water throughout the arid region of Spain and maintain agrarian practices. The only problem is that few people know how acequias work.

As Spain moved toward an agricultural model that emphasized reservoirs and many in rural communities in Spain moved to cities, knowledge of the acequias system dwindled. Only a handful of people in these communities know how to restore the acequias.

Historians and conservationists are working together to restore these systems and build back the generational knowledge required to operate them.

Spain's Andalusia region has a Mediterranean climate with long summers and dry winters.

When the Moors introduced the acequias to Spain and used it to move water more effectively through the mountains, they changed the landscape. Now the Andalusian provinces, Granada and Almeria, are the leading agricultural regions in Spain.

Acequias also replenish aquifers and feed streams and rivers that originate further down the mountain. As the water moves through acequias, it soaks into the soil and is stored in the bedrock until it's needed again.

In the 1960s, Spain began to favor using reservoirs for farming, pushing rural farmers away from small farms. Spaniards in rural areas started leaving for cities; according to the National Statistics Office, the country has lost around 28% of its countryside population over the past 50 years.

As people vacated these rural areas, around 15-20% acequias were abandoned.

The rising temperatures combined with the rise of industrial farms have left the Alpujarra region of Spain barren as water is diverted to larger, more financially lucrative farms.

Armed with garden tools, shovels, and pickaxes, these volunteer groups work together to help bring water back to drought-stricken areas.

In order to maintain functional operation, these communities need to build back strong generational knowledge of acequias.

The disappearance of this knowledge makes it harder to find acequias and know how to operate them.

In an interview with BBC, Jose Antonio Peña, an "acequiero" who tends to the acequias, said these customs are being lost because, "young people don't want to know about it."

"If you understand efficiency in terms of multifunctionality, then the traditional irrigation systems are much more efficient. They better retain water, they recharge the aquifers, they improve the fertility of the soils," Martín Civantos, a Spanish archaeologist coordinating the acequias project, told the New York Times.