This article is the first in a 2-part series about water, climate, and agriculture in New Mexico’s Lower Rio Grande Valley.

On a mid-July afternoon, ditch riders—men patrolling irrigation channels—twisted open steel gates cut into concrete waterways in New Mexico’s Lower Rio Grande River Valley, bathing pecan orchards in water and nurturing vibrant chile plants. At first sight, all seemed a healthy, hydrated green. Hours later, however, I stood on a bluff overlooking Elephant Butte Reservoir, my eyes tracing the bleached rocks that once marked the high water.

“It’s been a long time since water spilled over the dam,” said James Powell, Operations Manager for Elephant Butte Reservoir—water that irrigates about 90,000 acres of farmland in New Mexico and provides half the water supply of El Paso, Texas. “The reservoir is dropping about 2.5 feet per day,” he continued. “It will probably fall another 20 feet before we stop releasing water in late August of early September.”

Amid a decade-long drought, water storage on the Rio Grande in New Mexico has plummeted. In coming weeks, Elephant Butte is expected to dip to five percent of capacity; all stored water designated for farming and urban needs will be completely exhausted, according to the Bureau of Reclamation.

Until a string of wet years restocks the reservoirs, agricultural producers and urban residents will have to make do with whatever flows through the rivers and make up shortfalls with groundwater, an expensive and potentially unsustainable practice that is spurring novel efforts to corral monsoon rains in order to boost supplies.

Water stored in Elephant Butte Reservoir (as a percent of its full capacity of 2.195 million acre-feet) at the beginning of the water year on October 1. Graph by Climate.Gov team, data courtesy of the U.S. Bureau of Reclamation.

On the Rio Grande—historically the wellspring for more than five million people in Colorado, New Mexico, Texas, and Mexico—coping with scarcity has become a reality, and water management and use in the region may be a leading example of how to adapt to drier times.

Water Use

The Rio Grande flows about 1,800 miles from the peaks of southern Colorado to the Gulf of Mexico, forming a long stretch of the international border between the United States and Mexico. People use the water for different things along different stretches of the river. In northern New Mexico, Rio Grande water supplies a substantial portion of urban water needs for Albuquerque, while irrigation draws the most water in the middle and southern parts of the watershed in the state.

The Rio Grande provides water for more than five million people in Colorado, New Mexico, Texas, and Mexico. In New Mexico, it supplies a substantial portion of water for urban needs and irrigation, among other uses.

Managed by the U.S. Bureau of Reclamation, Elephant Butte is New Mexico’s largest reservoir on the Rio Grande, with a capacity of about 2 million acre-feet of water. (An acre-foot covers one acre of land in one foot of water and satisfies, on average, the annual water needs of about eight Albuquerque residents.) About 25 miles down river, Caballo Reservoir can impound an additional 350,000 acre-feet. In a good year, these reservoirs together release about 790,000 acre-feet; 416,000 is allocated to the Elephant Butte Irrigation District in southern New Mexico, and 314,000 and 60,000 acre-feet are passed to Texas and Mexico, respectively.

When flows in the river and storage in Elephant Butte and Caballo reservoirs are sufficient, the district doles out a full irrigation allotment of 3 feet of water per acre of land. In some years, they’ve allocated more; recently, allocation has been a lot less.

“In about 1979, we began a 24-year full-supply of surface water,” said Gary Esslinger, director of the Elephant Butte Irrigation District. “We had plenty of snowpack runoff. The lakes were full. We were just over our heads in surface water.”

In 2003, drought set in. It was a wake-up call, Esslinger said.