Environmental Advances (Oct 2023)
Advanced preparedness for drinking water emergency: Ensuring safe microbial quality with rapid microbial source tracking and E. coli methods
Abstract
The increasing occurrence of water main breaks attributed to aging water infrastructure and other disaster-related events amplifies the risk of microbial contamination in drinking water. Conventional methods for assessing water quality after waterline disruptions involve using time-consuming fecal indicator culture-based techniques that fail to detect the sources of contamination. Thus, rapid emergency responses are critically needed to safeguard public health and swiftly resume community functioning. This novel study proposes a rapid emergency response method targeting Escherichia coli (E. coli) and microbial source tracking (MST, human (HF183) and universal (UniBac) fecal contamination) following water main breaks to evaluate water safety. Objectives were: develop a rapid method for quantifying fecal microbial contamination using droplet digital PCR (ddPCR), and compare rapid results to culture-based method. Results indicate zero E. coli presence using culture-methods. Conversely, results using rapid-ddPCR method show quantifiable positive detection of E. coli and MST markers (HF183 and UniBac) across various sites, suggesting potential widespread fecal contamination following the main break incident. Results highlight that a rapid molecular E. coli and MST techniques effectively detected fecal contamination in treated drinking water that culture-based methods failed to detect. Notably, the ddPCR method produced sensitive results 18 hours faster than culture-based method, highlighting that MST can be used to simultaneously determine water quality and fecal contamination sources. To our knowledge, this is the first pilot study employing highly specific and sensitive MST methodology in treated drinking water following distribution main break.
