Groundwater depletion and sustainability of water-intensive agriculture in the Cuatro Ciénegas region, Coahuila, Mexico

This study examines regional groundwater depletion in Cuatro Ciénegas, Mexico, focusing on water-intensive agriculture. The study presents data from a comprehensive field campaign aimed at assessing water levels in aquifers located in and around Cuatro Ciénegas. To study regional groundwater flow and aquifer hydrogeological connectivity, isotope analysis is employed. Changes in water levels and data from the Gravity Recovery and Climate Experiment (GRACE) mission found groundwater depletion in all aquifers: Cuatro Ciénegas-Ocampo (average decline of -37.45 m from 2001 to 2023), Cuatro Ciénegas (-24.23 m from 2005 to 2023), and El Hundido (-20.17 m from 2005 to 2023). Isotope analyses indicate a hydrogeological connection between the Cuatro Ciénegas-Ocampo and Cuatrociénegas aquifers, suggesting agricultural practices threaten aquatic ecosystems. The agricultural frontier in the Cuatro Ciénegas-Ocampo and El Hundido aquifers increased by 63% and 68%, respectively, between 2003 and 2023. The Cuatro Ciénegas aquifer, located within a designated protection area for flora and fauna, registered a 7.6% reduction in the farmed area. The analysis linked groundwater depletion to water-intensive agriculture in the region, particularly regarding main crops. Due to the close relationship between cropland expansion and water-intensive crop production with groundwater use, water stress has increased since 2011. Groundwater extractions are driving the rise, worsening regional water stress. Since 2012, alfalfa fodder oat and corn production has exceeded the natural recharge capacity of the aquifers that comprise the protected area, depleting groundwater. Sustainable groundwater extraction and aquifer rehabilitation strategies are urgently needed.