Contamination of groundwater by microorganisms and risk management: Conceptual model, existing data, and challenges

Abstract

Groundwater, a crucial resource for drinking water and irrigation, is increasingly threatened by microbial contamination from bacteria and viruses, presenting serious public health challenges. This review offers a thorough exploration of the sources and pathways through which bacteria like fecal coliforms and enteric viruses infiltrate groundwater, highlighting key risk factors such as land use, poor sanitation, and climate change. It assesses both conventional and innovative risk management strategies, with a special emphasis on Quantitative Microbial Risk Assessment (QMRA) as a tool to gauge their effectiveness. The review aligns with Sustainable Development Goals (SDGs) concerning clean water and health, offering insights on how microbial contamination can be reduced to meet global targets. Furthermore, it addresses the specific difficulties faced by Small Water Systems (SWSs) in hazard identification, pathogen monitoring, and QMRA implementation, proposing an enhanced QMRA framework for these systems. By identifying knowledge gaps and suggesting future research directions, this review seeks to advance understanding of bacterial and viral contamination in groundwater, contributing to its safer and more sustainable use.