Taxonomy and Functionality of Bacterial Community in Pre-ozonated Biological Active Filters Treating a High-DOC Coagulated/Softened Water

This study examined the microbial community and function in pre-ozonated biologically active anthracite and silica sand followed by GAC filters treating high-DOC coagulated and softened water. Analyzing two filter types in winter and summer allowed us to investigate the effects of operational conditions, including temperature, backwashing cycle, and empty bed contact time on organic matter removal, microbial activity, and bacterial taxonomy and functionality profiles in consecutive full-scale biological active filters. Metagenomics sequencing of the full 16S rRNA gene was undertaken on the filters' media samples before and after backwashing and during air scouring. This analysis was employed to achieve a more comprehensive quantification of OTU profiles and to discern the functionality of the bacterial community in biological active filters while also assessing the impact of backwashing on the taxonomy and functionality of the bacterial community. The 16S rRNA V4-V5 region amplicon sequencing was conducted on both water and BAFs' media samples across seasons to understand the microbial transfer dynamics between the water matrix and the filter media.