Climate Change Puts New Mexico’s Ancient Acequias to the Test

A narrow, meandering ditch brings water from the Rio Grande into the orchard on Enrique Lamadrid’s north-central New Mexico property. The retired University of New Mexico professor and folklorist often marvels at the abundance of birds that flitter through the trees on its banks. “We have Great Horned Owls. We have several kinds of hawks, including the little gavilanes—the little kestrels,” he says. “We have all kinds of songbirds. We have wrens. We’ve got the Bewick’s Wren that sings up a storm.”

This small waterway is known as an acequia, an ancient type of gravity-powered ditch found throughout northern New Mexico. These earthen canals carry mountain snowmelt and rain to fields, orchards, and gardens. The emerald-green ribbons of vegetation that flourish as a result provide an oasis for a diversity of avian life, says Lamadrid, an avid birder who has researched acequias extensively. “We forget to give acequias credit, but acequias broaden and expand the riparian zone,” he says. “Where there are acequias, there are beautiful trees full of birds.”

Acequias (pronounced ah-SEH-kee-ahs), have a long history of delivering water for flood irrigation dating to the colonization period during the seventeenth and eighteenth centuries. They have helped people in New Mexico and other parts of the arid Southwest to endure times of both plenitude and scarcity. But severe weather this summer caused some acequias to run dry, raising concerns about whether these centuries-old symbols of resilience can continue to provide for communities as climate change causes deeper, longer-lasting water shortages.

Acequias stem from a blend of civilizations whose communal culture still thrives in the region. The ditches evolved over thousands of years in the Middle East. They spread to Spain during the North African Muslim occupation of the Iberian Peninsula in the eighth century. When the Spanish arrived in the Southwest, they used these irrigation techniques to build on similar canals that Pueblo Indians relied on to grow corn, beans, and squash.

New Mexico’s estimated 700 to 800 surviving acequias flow through both urban and rural communities, and their users are diverse. “Some are commercial farmers, and some are lucky enough to have an acequia in their backyards, but everybody benefits because they make this a very livable place,” Lamadrid says. In Santa Fe, the Randall Davey Audubon Center and Sanctuary draws water from the Acequia del Llano.

The old irrigation systems still function in much the same way as centuries ago, under principles of equity and cooperation. The word acequia, of Arabic origin, embodies not just the network of canals, but also a complex system of inherited cultural norms, shared responsibilities, and democratic decision-making. “It’s a privilege to use water communally,” Lamadrid says. “The acequia is physical and spiritual and communal values.”

State law recognizes acequias as political subdivisions and addresses related matters through the governor-appointed New Mexico Acequia Commission. Acequia traditions include self-governing practices and a distinct Spanish lexicon. Elected comisionados, or commissioners, manage the acequias. A mayordomo, or ditch manager, ensures fair distribution of water and acequia upkeep. Parciantes who hold water rights must help clean and repair the acequia madre every spring during la limpia, when people of all ages gather to cook, eat, and catch up with neighbors when the work is done. From this cherished main canal, the water flows into communities and is then allotted to parciantes via smaller ditches that flood individual plots.

Since water from typically unlined acequias infiltrates through their beds, some critics view them as less efficient than other methods of watering crops. Drip irrigation, for example, uses flexible tubing to slowly deliver water directly to plants, keeping evaporation and runoff to a minimum. Supporters, however, hold up acequias as a viable alternative to confront an increasingly warming climate. And science seems to support those assertions.

Studies from New Mexico State University show acequias provide multiple benefits for the environment. Not only do they expand and maintain riparian areas for increased bird and wildlife diversity, but water seepage from acequias replenishes shallow aquifers, feeding streams and rivers, says Alexander “Sam” Fernald, director of the university’s Water Resources Research Institute. To call these irrigation systems inefficient “is mischaracterizing the point of acequias,” he says. “Part of their function, historically and ideologically, is keeping the groundwater and surface water in balance, so they're actually the most efficient system for doing that.”

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Not only do they expand and maintain riparian areas for increased bird and wildlife diversity, but water seepage from acequias replenishes shallow aquifers.

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Maintaining that balance will be especially important and challenging in the coming decades, during which scientists predict that New Mexico will become even hotter and drier. Higher temperatures earlier in spring mean that acequia users will have to adjust to the snowmelt they rely on arriving sooner, says John Fleck, director of the Water Resources Program at the University of New Mexico. “If you’re a water user below a dam, where you can store spring runoff to use in the summer, you can correct for that problem,” Fleck says. “But most of the acequias are not below dams, so they’re victims of this fundamental change in the climate.”

Still, acequias have proven resilient during periods of severe drought and other external forces over the past 400 years, Fernald notes. The communal nature of acequias can provide cohesiveness to help meet the challenges of a changing climate head-on, without advanced irrigation technologies or major infrastructure, he says.

Parciantes already are adjusting their approach. In Albuquerque’s North Valley, where Lamadrid lives and the acequias bring water from the Rio Grande, drought this summer forced the system to shut down three months earlier than usual. “Farmers put their fields to bed for the winter when they water one last time in the middle of October,” says Lamadrid, a comisionado for Alamos de los Gallegos Acequia Association. “This year, they cut the cycles off by the end of July.”

Monsoon rains brought some temporary relief, allowing farmers and gardeners to water their fields and plots a few more times. “We’re still in the middle of a drought, but this year we had a very generous temporal,” says Lamadrid, using the Spanish word for seasonal rain that fell intermittently through September.

In East Pecos, state commission chairman Ralph Vigil is mayordomo of the Acequia del Molino. An eighth-generation farmer in the Pecos River Valley, he has started growing more drought-tolerant crops that he sells to schools. He views acequias as an integral part of thriving habitat for birds and other creatures throughout the state: “The growth along the acequias, along those corridors where that water basically leaches through, allows this plant life that sustains the birdlife and the insect life and every piece of wildlife in there.”

Vigil and parciantes around New Mexico hope that acequia communities will be able to adapt to a changing climate and preserve a time-honored water-sharing culture built on querencia, a deep love of place that also involves respect. “We were all taught about querencia of ourselves, of community, of the land and the place that we were brought up in,” Vigil says.

This heritage passed on from one generation to another, he says, can help sustain acequias in a region they helped to build centuries ago, and where they still belong.