AWWA JAW73198

Biologically active filters (BAFs) are applied in drinking water treatment to remove contaminants such as natural organic matter, nitrate, trace organic compounds, perchlorate, sulfate, iron, and manganese. BAFs and other biological water treatment processes make use of microbial communities to metabolize contaminants through mediating oxidation- reduction reactions. This study was undertaken first to address the lack of knowledge about microbial communities in BAFs and associated treatment units upstream and downstream and second to pinpoint ways to control or improve filtration performance. A comprehensive review is provided of state-of-the-art knowledge about BAFs, their operating parameters, and microbiological approaches to control of biological activity in the filters. Controlling biofilm thickness and producing microbial communities fully adapted to targeted contaminants constitute significant scientific and engineering challenges. A better understanding of the microbial communities in BAFs will help identify solutions to optimize their performance, alleviate concerns about pathogenic breakthrough, and lower operating costs.

Includes 127 references, table, figure.