Using Amplicon Sequencing To Characterize and Monitor Bacterial Diversity in Drinking Water Distribution Systems

Area of Science:

• Environmental Microbiology
• Water Quality Management
• Molecular Biology

Background:

• Traditional drinking water assessments rely on limited microbial, physical, and chemical indicators.
• These indicators fail to characterize complex bacterial communities impacting drinking water distribution systems (DWDSs).
• Targeted metagenomic amplicon sequencing offers a rapid and cost-effective approach to study entire bacterial communities.

Purpose of the Study:

• To assess the bacterial communities in two distinct full-scale DWDSs using 16S rRNA gene sequencing.
• To compare the effectiveness of different water treatment regimes on bacterial communities.
• To understand bacterial repopulation and interactions within DWDSs.

Main Methods:

• Conducted 16S rRNA gene amplicon sequencing alongside traditional water quality measurements.
• Analyzed bacterial communities in two full-scale DWDSs with different treatment strategies.
• Investigated microbial profiles in relation to water chemistry and disinfection byproducts.

Main Results:

• Bacterial communities significantly shifted post-disinfection in both DWDSs.
• Bacterial repopulation was observed downstream, with some end-user samples resembling source water.
• Nitrification was detected in three locations, and disinfection-resistant genera like Burkholderiales were abundant.
• Pathogenic and fecal-associated bacterial genera were identified in several samples.

Conclusions:

• Metagenomic amplicon sequencing is a valuable tool for understanding DWDS bacterial ecology.
• This method complements traditional compliance-based monitoring.
• It provides insights into bacterial community interactions with water treatment and distribution environments.