Spatial Variability of Uranium in Shallow Aquifers of Semi-Urban Indian Landscapes

Uranium contamination in shallow aquifers is emerging as a concern for groundwater-quality issues across several parts of India. The present study evaluates the spatial distribution, concentration levels in shallow groundwater systems of selected semi-urban regions of India. Secondary data used in this assessment were obtained from the Central Ground Water Board (CGWB), covering semi-urban areas across all Indian states. The results reveal pronounced spatial heterogeneity in uranium concentrations, with numerous locations exceeding the permissible limits prescribed by the World Health Organization (WHO) and the Bureau of Indian Standards (BIS) for drinking water. Analysis of uranium concentration data for the period 2024–2025 indicates that shallow aquifers in parts of Karnataka, Punjab, and Rajasthan exhibit average uranium concentrations of approximately 133 ppb, 48 ppb, and 79 ppb, respectively, while maximum concentrations of 488 ppb, 202 ppb, and 119 ppb respectively, were recorded at select locations. A substantial proportion of groundwater samples were found to exceed WHO guideline values, highlighting widespread contamination concerns. The findings of this study offer critical insights for water-resource managers and policymakers in developing strategies to protect drinking-water security in uranium-affected regions of India.