Multi-indices approach for comprehensive appraisal of groundwater quality and the implication on human health in the Amaravathi basin, Southern India

Groundwater is often used directly by the public in several river basins of India. Hence, this study was carried out with the objective of assessing the quality of groundwater in the Amaravathi basin, India, using a multiple indices approach. Groundwater quality data from 96 monitoring wells were obtained from the Central Groundwater Board and used in this study. Drinking water quality index (DWQI) and irrigation water quality index (IWQI) were calculated to assess the water suitability for consumption, irrigation, and farming. High levels of fluoride and nitrate have a detrimental impact on health and were evaluated using USEPA methods by calculating the chronic daily intake and hazards quotient. Findings revealed that 42% of samples did not meet the DWQI standards due to high salinity, hardness, nitrate, and fluoride levels. Health risk assessment (HRA) of hazard quotients of nitrate are 81%, 61%, and 39% of samples, while those of fluoride are 85%, 68%, and 18% of samples for infants, children, and adults, respectively are unfit. High salinity rendered 35% of the sample unsuitable for irrigation, though most remained suitable for livestock. Spatial analysis revealed declining groundwater quality from the center to the east of the basin. This mapping study identified areas where the groundwater quality is inappropriate for the intended purpose and alternate water sources should be made viable.