Evaluation of irrigation suitability of groundwater from the semi-arid Oriental Basin in eastern-central Mexico

Water from the deficit Libres-Oriental aquifer is used for irrigating agricultural fields in the semi-arid Oriental Basin of eastern-central Mexico. Its chemistry (Ca–Mg–HCO 3 ) is influenced by ion exchange and silicate weathering of the volcaniclastic lithologies and dissolution of karstic rocks. Multiple approaches such as the US Regional Salinity Laboratory (USSL) categorization, Donnen classification and Wilcox diagram as well as estimation of the irrigation water quality index (IWQI) were used to evaluate its irrigation suitability by collecting samples from different wells within the basin. Water from about 60% of the sampled wells, showing high and very-high salinity hazards, remained unsuitable in the USSL categorization. It should be avoided for irrigating salt sensitive plant, and soil in the irrigated fields might also need permeability enhancement. Computed IWQI values were mostly congruent, and they demarcated the wells at western and southern parts of the basin as suitable (low restriction) for irrigation. • Irrigation suitability of groundwater through IWQI index. • Volcano-sedimentary nature in Libres-Oriental aquifer (Mexico). • USSL categorization suggesting unsuitability of 60% wells. • Demarcation of suitable wells within the semi-arid basin.