Assessment of Physicochemical, Microbiological, and Water Quality Index (WQI) Parameters of Water Bodies in Ranchi, Jharkhand, India: A Comprehensive Study of Surface and Groundwater Quality

Abstract

Water quality assessment is fundamental to sustainable water resource management and the protection of public health. This study evaluated physicochemical, microbiological, and heavy-metal parameters across six surface water bodies (Ranchi Lake, Kanke Dam, Dhurwa Dam, Patratu Dam, Line-tank Lake, and the Harmu River) and groundwater from six geological formations (Bundu, Rahe, Namkum, Kanke, Ratu, and Nagri) in the southern region of Ranchi district, Jharkhand, India. Sixteen physicochemical parameters, together with arsenic, chromium, total coliforms, and Escherichia coli, were analysed. Urban surface water bodies, particularly Ranchi Lake, Line-tank Lake, and the Harmu River, showed marked pollution, with chloride, sulphate, BOD, and COD values frequently exceeding the limits specified in Bureau of Indian Standards (BIS) 10500:2012; the Harmu River was classified as critically polluted (CPCB pollution score = 81.20). Groundwater in the southern region generally complied with BIS limits, although Water Quality Index (WQI) analysis revealed considerable spatial variation, ranging from excellent (Ratu, WQI = 28.86) to very poor (Rahe, WQI = 203.3), with 50% of the locations classified as having good water quality. Escherichia coli was detected at half of the groundwater sites, indicating localised faecal contamination. Correlation analysis confirmed a strong TDS–EC relationship (r = 0.99), while one-way ANOVA showed no statistically significant overall difference among locations (p = 0.70), despite marked variability in individual parameters. The findings indicate the need for sewage-treatment infrastructure, regular monitoring programmes, and public-awareness campaigns to safeguard Ranchi's water resources.