Drinking Water Biofiltration Performance With Varying Ozone and Hydraulic Operations

This study produced a comprehensive drinking water ozone‐biofiltration evaluation by assessing performance at a newly commissioned facility with varying hydraulic and ozonation operations. In brief, 30 water quality, operational, and biological parameters were collected at 11 locations throughout the treatment train at least every other week for an entire year. Seasonal and environmental variation seemed to influence treatment performance more than operational changes (i.e., ozone or hydraulic re‐rating). However, media adenosine triphosphate (ATP), an indicator of biomass, was sensitive to hydraulic variability. Organic carbon was identified as a reliable performance metric, particularly when total organic carbon (TOC) and dissolved organic carbon (DOC) shared a strong linear relationship. Carboxylic acid removal also served as a useful long‐term monitoring tool for assessing ozone‐biofilter performance. This study establishes a critical benchmark for capturing the effects of intermittent ozonation, variable hydraulic loading, and seasonal transitions that utilities can utilize to better understand ozone‐biofiltration processes in drinking water treatment systems.