Optimizing Biofilm Processes for Drinking Water Treatment

Over the past six years, Dr. Gagnon's team has studied biofilms and their role in drinking water processes such as biofiltration and distribution systems. Dr. Gagnon's research was critical in converting a full-scale treatment plant from conventional filtration to biofiltration, while reducing disinfection by-products by 40%. Dr. Gagnon's research in distribution systems has been critical for utilities in their efforts to reduce lead release to drinking water. Over the next five years, Dr. Gagnon's long-term objective is to make new discoveries in biofilm engineering. His research program will explore interactions between biofilm and metals in model drinking water systems. Specifically, his team will develop new approaches to detect extracellular material in biofilms and use these analytical approaches to assess and optimize process design for biofiltration and corrosion. In addition to improving process operations, Dr. Gagnon will develop new clean technologies that (i) use graphene-based epoxies for biocorrosion inhibition and (ii) reverse engineer biofilm properties to create bioactive surfaces to promote bioadhesion of colloidal material and dissolved metals.This research program will provide a training ground for multi-disciplinary research where undergraduate (UG) trainees through to PhD students can develop new skills in corrosion chemistry, microbiology, process engineering and materials engineering. Highly qualified personnel (HQP) in Dr. Gagnon's laboratory work as part of intersecting teams based on research area and level of training, which allows for knowledge transfer and leadership opportunities. In the last 6-years, Dr. Gagnon has trained 19 PhD, 39 Master's and 35 UG students. Alumni from his program have been hired by Health Canada, Halifax Water, LuminUltra Technologies, Associated Engineering and beyond. It is anticipated that 11 HQP (five UG, two Master's, four PhD) will be trained directly from this program, with additional training opportunities available through other leveraged opportunities in Dr. Gagnon's laboratory.This research program will contribute to the understanding of biofilm-metals interactions that cause public health challenges in drinking water systems. One such challenge is the formation of Legionella biofilms (the causative agent for Legionnaires' disease). A total of 88 Legionnaires' disease cases and 12 deaths were reported during the Flint Water Crisis. Legionella has been associated with active biomass concentration, and more recently in the case of Flint, metals release caused by water corrosivity. By contributing to the development of solutions for these types of biofilm-metals interactions, with the novel emphasis on extracellular material, it is anticipated that this research program will help inform applied research in Canada and train new engineers for challenges in the water and clean technology sectors.