GIS-Integrated Groundwater Flow Modeling for Heterogeneous Media: Application to the Calera Aquifer

Groundwater resources management is a critical issue for populations in regions with significant growth. In arid and semiarid regions, where rainfall is scarce, groundwater is often the only source of water for all their needs. Nevertheless, groundwater characterization is virtually unknown in countries with limited infrastructure and resources. A short-term solution is to study groundwater through numerical simulation using the limited available data. We developed a GIS-integrated groundwater flow scheme based on the finite-difference method to numerically simulate a heterogeneous medium using surface geological information. We validate our implementation by comparing it with MODFLOW. We performed groundwater simulations of the Administrative Aquifer in Calera, Zacatecas, Mexico, using homogeneous and heterogeneous media to evaluate flow changes resulting from heterogeneities. We found that numerical simulations show flow barriers in low hydraulic-conductivity zones that coincide with the administrative boundaries of the aquifer; however, in high hydraulic-conductivity zones, the administrative aquifer boundaries do not match the geological limits of the aquifer. This finding gives insight into reconsidering the administrative boundaries of some aquifers in the region for their sustainability, with an integral understanding of groundwater.