Bacterial growth during the start-up period of pilot-scale biological activated carbon filters: Effects of residual ozone and chlorine and backwash intervals

- We employed ATP analysis and flow cytometry to evaluate pilot-scale BAC filters.
- The effects of residual ozone and chlorine and backwash intervals were evaluated.
- Residual chlorine caused 1-log reduction of ATP-per-cell in all bacterial cells.
- High residual ozone decreased the attached bacterial density and removal of DOC.
- Extending the backwash interval made the attached bacteria more resistant to oxidants.