Lake Chapala and the Cienega aquifer: Chemical evidence of hydraulic communication

Abstract

A hydraulic communication mechanism between Lake Chapala and the Cienega de Chapala aquifer system is proposed. The lake is a recharge area and a potential source of aquifer pollution. In 1910, 56 % of the Cienega was occupied by the lake. The communication hypothesis is supported by piezometry, phosphate and chlorine gradients that suggest flows from the lake to the aquifer.
The high content of clay in the shallow layers controls the agriculture phosphate leakage. A proposed mixed functional model is based on the aquifer hydrostratigraphic model, the main recharge mechanisms and the chemical and piezometrical tendencies.