Mexico

A model to manage a precious groundwater resource

More than half a million people around Independence Basin in central Mexico rely heavily on groundwater for drinking, as well as for agricultural and industrial use. The water table, however, is rapidly dropping, a natural process amplified by over-pumping of the upper granular aquifer for industrial irrigation. “In 20 years, it will all be desert,” said JW Molson. As the underground water-level sinks, it inches closer to the hot layer of volcanic rock under the earth’s surface. This heats the water and dissolves contaminants such as arsenic, fluoride and sodium, making it unsafe to drink.

Dr. Molson’s visit to the basin provided first-hand knowledge of the scale of the water resource problem, while Adrian Ortega’s visit to the Université Laval brought new understanding of the regional geology and advanced tools. Together, they developed a preliminary flow model that illustrated differences between historical and recent conditions, as well as a heat-transport model that showed how deep higher temperature groundwater could be drawn up towards intensive groundwater pumping zones.

The Mexican partners now have new modeling tools to help interpret field data, which should lead to new solutions and strategies. Indeed, the partners will be able to work with local communities to improve aquifer management at the basin scale. Building on results to date, the universities planned to develop more detailed numerical models that can help predict what will happen to the aquifer in 10 years.