Water quality in the central zone of the Texcoco aquifer

Abstract

Objective: Determine the water quality in the central zone of the Texcoco aquifer for human use and consumption and agricultural use.

Methodology: Physical, chemical and biological indicators of the water from 16 wells located in urban areas of the central zone of the aquifer were determined. Sampling, determination of the parameters and definition of its quality by uses was made based on current official Mexican standards.

Results: According to the physical indicators and the concentrations of CO₃^2-, HCO₃^-, Ca²⁺, Mg²⁺, Cl^-, SO₄^2-, PO₄^3-, Na⁺, K⁺, Fe, Cu and Zn, the water was suitable for human consumption and agricultural use in the 16 wells studied. Based on the Cadmium concentration (Cd), the water was unsuitable for human consumption and agricultural use, in 12 and 6 wells, respectively. According to the found concentration of Lead (Pb), the water was suitable for agricultural use in the 16 wells studied, but in all of them it was not suitable for human consumption. Water did not meet the microbiological quality required for human consumption in eight of the wells analyzed, but was suitable for agricultural use in all the study wells.

Implications: This study complements the research carried out in other areas of the aquifer. The causes of water contamination are unknown and it would be convenient to investigate the vulnerability of the aquifer and possible sources of contamination.

Conclusions: The aquifer water in the central zone has limitations for human use and consumption and agricultural use due to the high concentrations of Cd, Pb and poor microbiological quality.