Improved Risk Categorization at Grass-root Level to Prevent Microbial Contamination of Rural Water Supplies

Abstract Background: Microbial pollution of water supplies caused morbidity and mortality in nine villages of Karnataka during December 2019 and August 2024 from fecal contamination of tube wells, the inflow of wastewater into piped networks, unclean tanks, and inadequate disinfection. This study aims to strengthen risk categorization at grass-root level to prevent microbial contamination of rural water supplies. Methodology: Information on the water supply systems, the number of families with tap water connections, and the quality of the drinking water in the affected villages was extracted from the Jal Jeevan Mission Citizen Corner website. Information on the hazard events, morbidity, and mortality caused by contaminated drinking water in the affected villages was extracted from online newspaper reports. Results: The water supply systems in the affected villages of Karnataka mainly rely on groundwater for their drinking water needs and lack provision for water disinfection. The existing sanitary inspection survey assigned identical points to hazards irrespective of their impact on public health, which led to improper risk evaluation in the affected villages. The current approach is modified to account for the relative impact of hazards on human health by multiplying the assigned marks for the hazard with a severity ranking. Conclusions: The risk categorization of rural water supply systems from microbiological pollution is reinforced by the assignment of severity scores to the hazards. An equation is developed to predict the % morbidity in a village population based on the risk category of the water supply systems.