Delimitation of potential zones for groundwater recharge and discharge in the Guayalejo–Tamesi River Basin, southern Tamaulipas, Mexico

The Guayalejo–Tamesi River Basin (GTB) has suffered from water scarcity mainly due to aquifer overexploitation, limited understanding of the surface water – groundwater relationship, and poor water resource management. Given this, appropriate land use can be a decisive factor in sustainable water management. In this context, the present study focuses on delineating potential groundwater recharge zones (PGRZ) and discharge zones (PGDZ) to achieve an overview of groundwater flow systems and thus preserve areas of hydrogeological importance. This analysis was conducted using a Geographic Information System (GIS), integrating satellite data, geophysical information, and terrain surface characteristics. Based on these databases, ten hydrogeological variables were obtained and assessed using an Analytical Hierarchy Process (AHP) based on Groundwater Flow System Theory (GFST) criteria. This resulted in two mathematical models estimating that 37.71 % and 11.78 % of the GTB exhibit PGRZ and PGDZ conditions, respectively. The models were validated by comparing the delineation of PGRZ and PGDZ with the locations of 222 springs and the chemistry of 30 groundwater samples, showing an accuracy of 75 % for the PGRZ calculation and 70 % for the PGDZ model. The model proved sufficiently accurate for identifying small PGRZ and PGDZ, thus providing a regional understanding of hydrogeological characteristics and groundwater flow dynamics at a local resolution.