Project #4984

Impact of Intermittent Operation on Biofilter Performance

In Progress
Principal Investigator
Research Manager
Ms. Stephanie Fevig, PE
University of Toronto
Water Quality


In an effort to improve safety and reduce reliance on outside suppliers, the Eugene Water and Electric Board (EWEB) will cease purchasing chlorine gas, and commence on-site production of sodium hypochlorite for disinfection at the Hayden Bridge Filtration Plant (HBFP). To reduce costs, chlorination of raw water and the use of chlorinated backwash has been eliminated. As the anthracite and sand filters will no longer be exposed to residual disinfectants, it is anticipated that biological acclimation will occur.

The objective of this study is to evaluate the transition to biological filtration, determine optimal filter shutdown duration (at pilot-scale), and subsequently identify an appropriate operating schedule for full-scale trials. Results of this study will be used to characterize the impact of biofilter shutdown on biomass characteristics and identify an operating strategy that will improve treated water quality while reducing overall treatment costs. It will benefit EWEB by providing insight regarding the operation of biologically active filters, as well as operating information for future increases in demand. Tailored Collaboration Partner: EWEB.