The dynamics of the underground part of the water cycle greatly influence the features and characteristics of the Earth’s surface. Using Tóth’s theory of groundwater flow systems, surface indicators in Mexico were analyzed to understand the systemic connection between groundwater and the geological framework, relief, soil, water bodies, vegetation, and climate. Recharge and discharge zones of regional groundwater flow systems were identified from evidence on the ground surface. A systematic hydrogeological analysis was made of regional surface indicators, published in official, freely accessible cartographic information at scales of 1:250,000 and 1:1,000,000. From this analysis, six maps of Mexico were generated, titled “Permanent water on the surface”, “Groundwater depth”, “Hydrogeological association of soils”, “Hydrogeological association of vegetation and land use”, “Hydrogeological association of topoforms”, and “Superficial evidence of the presence of groundwater flow systems”. Mexico’s hydrogeological features were produced. The results show that 30% of Mexico is considered to be discharge zones of groundwater flow systems (regional, intermediate, and recharge). Natural recharge processes occur naturally in 57% of the country. This work is the first holistic analysis of groundwater in Mexico carried out at a national–regional scale using only the official information available to the public. These results can be used as the basis for more detailed studies on groundwater and its interaction with the environment, as well as for the development of integrative planning tools to ensure the sustainability of ecosystems and satisfy human needs.

Consideration of regional groundwater flow in aquifer systems allows for solving groundwater issues on a larger scale than single aquifers and contributes to all practical aspects of the UN’s Sustainable Development Goals for water. The approach has been extended to a wide range of hydrogeological environments. However, it suffers from poorly constrained terminology and conceptualisation, compounded by the difficulties of interpreting complex groundwater flow systems. This essay aims to initiate a discussion on improving the application of regional groundwater flow approaches.