BOOK OF ABSTRACTS 129 IHSS&IWA26 / BRNO / CZECHIA / 23–28 August 2026 Thursday, 27 August 2026 / Hall C NOM and Aquatic Systems SL62 Dissolved Organic Matter Diversity as a Predictor of DBP Formation and Composition Across Canadian Watersheds F. Amiri1, M.B. Emelko1, S. Ngo1, J. Orlova2, D. Olefeldt2, A.K. Bourgeois3,4, J.M. Buttle5, E. Cherlet2, C.W. Cuss6, K.J. Devito3, W.C. Floyd4, D.E. Foster7, R.H.S. Hutchins8, R. Jamieson7, M.S. Johnson9, H.J. McSorley4,9, U. Silins2, S.E. Tank3, L.M. Thompson2, K. Webster10, C. Williams2 1 Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada, Email: f3amiri@uwaterloo.ca 2 Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada 3 Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada 4 Coastal Hydrology Research Lab, Vancouver Island University, Nanaimo, BC, Canada 5 School of the Environment, Trent University, Peterborough, ON, Canada 6 School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL, Canada 7 Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada 8 Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON, Canada 9 Institute for Resources, Environment, and Sustainability, University of British Columbia, Vancouver, BC, Canada 10 Great Lakes Forestry Centre, Sault Ste. Marie, ON, Canada Drinking water supplies across much of the United States and Canada are sourced from forested catchments, where treatment performance is closely linked to both the concentration and composition of dissolved organic matter (DOM). To investigate how DOM influence disinfection by-product formation in Canadian forested systems, over 400 stream water samples collected from six watersheds across Ontario, Alberta, British Columbia, and Nova Scotia, encompassing the country’s major forested ecozones [1], were analyzed. A range of key water quality parameters, including pH, alkalinity, dissolved organic carbon (DOC), and specific ultraviolet absorbance (SUVA) were measured. DBP formation potentials were quantified, and a subset of samples underwent detailed DOM characterization using both conventional and advanced analytical methods, including UV–Vis spectroscopy, Fourier totransform ion cyclotron resonance mass spectrometry (FT-ICR-MS), and liquid chromatography–organic carbon detection (LC-OCD). Results indicate that while DOC concentration is the primary driver of DBP formation, the concentration and composition of trihalomethanes (THMs) and haloacetic acids (HAAs) are further governed by DOM characteristics —
RkJQdWJsaXNoZXIy NDA4Mjc=