On July 19, the University of New Mexico (UNM) announced a study conducted by David Gutzler, professor in the Department of Earth & Planetary Sciences, and UNM students, in collaboration with other regional universities led by the University of Texas-El Paso. The study investigated the potential impacts of different intervention scenarios on agricultural water supplies in the Rio Grande Valley downstream of Elephant Butte Reservoir.
“We carried out a six-year effort with a big interdisciplinary team, including hydrologists, economists, and agriculture experts, to explore the water future of the transboundary region along the Rio Grande, and to think about potential ways that the community could adapt to projected diminished water supplies,” said Gutzler, according to a press release by UNM.
According to the press release, the study titled "Adapting irrigated agriculture in the Middle Rio Grande to a warm-dry future" took into account climate model projections indicating that New Mexico's future will be characterized by increased temperatures and decreased precipitation, resulting in reduced water supply from the Rio Grande. Policymakers and agricultural stakeholders are faced with daunting challenges due to these projections. Led by professor Gutzler, along with UNM students and collaborators from other regional universities, including the University of Texas-El Paso, the study extensively investigated the potential effects of various land and water management interventions on agricultural water supplies in the Rio Grande Valley downstream of Elephant Butte Reservoir.
“The principal UNM-based component of the research was to make projections of future river flows into Elephant Butte reservoir,” Gutzler said, according to the press release. “We started with US Bureau of Reclamation model projections of natural river flows in a future climate warmed by increasing greenhouse gases. But we couldn't use the natural flow projections directly. The actual Rio Grande flow that reaches Elephant Butte is nowhere near natural because we're withdrawing lots of the water upriver, putting it to beneficial use in Colorado and northern New Mexico. So, our research came up with a way to turn the simulated natural flows reaching the reservoir into something more realistic, accounting for upstream water withdrawals.”
This research holds significant implications for New Mexico, as it not only focused on hydrology and climate change but also highlighted the critical aspect of water management related to interstate and international agreements for water distribution, according to the press release. The study actively engaged communities sharing water resources in southern New Mexico, western Texas, and across the border in the Mexican state of Chihuahua.
Researchers examined 19 different intervention scenarios, ranging from the implementation of deficit irrigation and adjustments in crop patterns using existing crops to the introduction of new drought- and salt-tolerant crop alternatives. The hydrological simulations were conducted using the soil and water assessment tool (SWAT) model, although the study acknowledged the model's limitations in performing scenario simulations.
Overall, this research offers invaluable insights into tackling water scarcity challenges and provides potential strategies for sustaining irrigated agriculture in the face of an evolving climate.
"In academia, we are in the business of assessing options and saying, here's what's feasible, and here's what's likely to happen in terms of water futures if you do option A and don't do option B," said Gutzler, according to the press release. "Our hope is that studies like ours can help inform policymakers about their best options in this contentious discussion."
