The report points to major changes for agriculture in the Upper Rio Grande Basin

Taking more arable land out of production and increasing irrigation efficiency on farms were two of the management options that could boost water flow in parts of the parched Rio Grande, according to the first Upper Rio Grande Basin Report Sheet released Thursday.

“In some areas the basin is doing well while in others it is struggling or even failing,” said Alexandra Fries, program manager at the University of Maryland Center for Environmental Sciences (UMCES), which has produced attestations for river basins around the world . For this report, UMCES worked with Audubon Southwest, the University of Massachusetts-Amherst, the World Wildlife Fund and local attorneys.

The upper Rio Grande Basin extends from the river’s headwaters in south-central Colorado through New Mexico to Texas, where it straddles the border with Mexico. The basin suffers from limited water availability due to climate change, interstate water management issues, aging infrastructure, and increased water demands from a growing population.

The researchers considered more than two dozen river basin health metrics, which fell into four categories: governance and management, society and culture, water quality and quantity, and landscape and ecology. While the pool received a C overall, it fared much worse on some metrics. For example, Annual Low Flow, which looks at the average flow for the driest seven-day period of each year, received an F.

The report finds that while Colorado farmers in the basin made progress in raising water tables from 2013 to 2018 after initiating conservation efforts, the recent drought has reversed that achievement. Things are worse downriver in New Mexico, where reduced water flow from Colorado is reducing irrigation supplies to farmers until early summer. Additionally, Southern New Mexico’s Elephant Butte Reservoir — which could store enough water to irrigate nearly 200,000 acres — has been nearly dry in recent years.

For the first 100 miles of the Rio Grande in Colorado, the river stays close to its natural flow, according to testimonies, but things get progressively worse as it flows through New Mexico. Below Elephant Butte Reservoir, for example, “the river’s natural heartbeat has been almost completely extinguished and native fish and animal species have disappeared,” the testimony says. By the time the river reaches Fort Quitman, Texas on the border with Mexico, it is completely dry.

Casey Brown, a professor of civil and environmental engineering at the University of Massachusetts-Amherst, helped model options for improving river management and mitigating the effects of climate change. Though the region is likely to get warmer, Brown said, it’s unclear what the precipitation patterns will be. “The variability of precipitation will be the biggest challenge,” he said.

According to Brown’s model, total flow could be increased by leaving a percentage of agricultural fields fallow along the river, increasing agricultural irrigation efficiency, and relaxing regulations so that more water is stored in upstream reservoirs, where evaporation rates are lower.

Cleave Simpson, a farmer and Colorado state senator who worked on the testimony, said the Colorado legislature recently allocated $30 million to help the Rio Grande Water Conservation District limit groundwater pumping for agriculture to reduce. Simpson said farmers should also consider growing less water-intensive crops, noting that this was his first time growing hemp. “I used half the amount of water I would have for other plants,” he said. “I think there’s room for that kind of innovation.”

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