Flow path delimitation in a groundwater flow system discharging into Mexico's majorlakes

This study investigates the groundwater flow trajectories within the Cuitzeo Groundwater Flow System (GFS) in the center of Mexico, the home of the second and third biggest lakes of Mexico. We employ the End-Member Mixing Analysis (EMMA) statistical method, water table configurations and structural features, utilizing semiconservative species such as Sr2+, Li+, and Cl− in order to better understand the pattern of groundwater circulation that is essential for sustainable management of groundwater resources.

Three distinct flow trajectory groups are identified: local, intermediate, and regional, each exhibiting unique hydrochemical characteristics. Local trajectories are linked to recharge waters, whereas intermediate trajectories indicate a progression towards more evolved waters. The regional trajectories, associated with fault zones along the shoreline of Lake Cuitzeo, reveal higher temperatures, suggesting geothermal influences. The lakes were fed by groundwater discharge of different flow paths, Lake Pátzcuaro is fed by local and Cuitzeo by local, intermediate and regional flow paths.

Extensive groundwater extraction, particularly during the dry season and due to the demands of avocado plantations, negatively impacts groundwater and lake levels. This extraction for agricultural purposes significantly alters the natural flow patterns and hydrochemical characteristics of the lakes.
This research highlights the need for integrated water resource management strategies that account for the interconnectedness of local, intermediate, and regional flow systems. Additionally, it brings international attention to the impact of avocado plantations on groundwater systems.