Biofilm Formation and Control In A Model Drinking Water Distribution System With Phosphorus Addition

Abstract

Biofilm formation on the internal surface of pipeline becomes a great concern as the majority of the microbial growth in drinking water distribution systems (DWDS) is associated with biofilm development. Phosphorus is recognized as another important limiting nutrient besides organic carbon in DWDS. The purpose of this study is to provide an in-depth understanding of the biofilm formation and control in DWDS when phosphorus addition is implemented. The primary conclusion from this research is that phosphorus addition to phosphorus-limiting drinking water will not only increase biofilm cell number, but also decrease the biofilm EPS quantity and change biofilm matrix structure. With phosphorus addition, disinfection efficacies were found to be increased especially for monochloramine. Biofilm metabolic activity was found to increase dramatically and biofilm community structure was found to change with phosphorus addition. As phosphorus addition has the potential to increase the microbial activity and pathogenic bacteria growth, cares must be taken when phosphate-based corrosion inhibitors are applied in DWDS to avoid the potential health-related problems.