Assessment of Water Quality among Various Domestic Water Storage Tanks in Urban Area, Belagavi—A Cross-sectional Study

Background: Unhygienic household water storage is a significant contributor to the deterioration of water quality from source to consumption, elevating the risk of waterborne diseases in urbanizing areas of India. The physical condition and maintenance of domestic water storage tanks are critical yet frequently overlooked factors in public health. Objectives: To assess water quality among various domestic water storage tanks in urban areas. Methods: A cross-sectional study was conducted from March to August 2025, involving 207 households selected through a proportionate-to-size sampling method. Water samples were analyzed for physical, chemical, and microbiological parameters. The physical condition of the tanks was evaluated using a risk assessment score, while overall water quality was summarized using the water quality index (WQI). Results: Microbiological analysis revealed significant fecal contamination, with E. coli present in 16.43% of samples and total coliforms in 23.67%. While 74.88% of tanks were in the low-risk category, 7.25% were classified as critical. Poor physical conditions such as the absence of a lid, cracks, and infrequent cleaning were significantly associated with poor WQI ( P < 0.0001). A moderate positive correlation (ρ = 0.48, P < 0.0001) was found between the physical risk score and WQI. This correlation confirms that tanks with greater physical defects (higher risk score) had poorer water quality (higher WQI), confirming that water quality declined as physical defects increased. Conclusions: The physical integrity and sanitary maintenance of domestic water storage tanks are significant determinants of household water quality. Observable physical deficiencies are directly linked to microbiological contamination, presenting a critical point for public health intervention. Routine cleaning and ensuring tanks are securely covered are crucial preventative measures.