The purity of groundwater in Nannilam Taluk, which is situated in the Cauvery delta region of Tamil Nadu, India, is the primary focus of this investigation. In order to evaluate the physicochemical properties and efficacy of the groundwater for irrigation purposes, a total of 100 samples were collected from open wells, bore wells, and hand pumps during two distinct seasons (premonsoon and postmonsoon) in 2022. The samples were subjected to analyses for pH, electrical conductivity (EC), total dissolved solids (TDS), and main ions, including , and . The data were analyzed using a variety of geochemical indices, including the sodium adsorption ratio (SAR), residual sodium carbonate (RSC), and permeability index (PI). Furthermore, spatial and statistical analyses were implemented, particularly principal component analysis (PCA) and a correlation matrix. It indicates that 16% of premonsoon samples and 12% of postmonsoon samples were classified as brackish. The premonsoon period is characterized by seasonal fluctuations that suggest an increase in salinity. This phenomenon may be linked to human activities, degradation processes, and ion exchange. The groundwater generally meets the irrigation criteria; however, elevated sodium and salinity levels in certain regions may pose challenges. The study underscores the necessity of monitoring and management to guarantee the long‐term sustainability of groundwater in the region.
Radhakrishnan et al. (Thu,) studied this question.