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With an historical onus on reactive water treatment in North America, most taste and odour (T&O) outbreaks and other water quality issues have been unanticipated and difficult to control Recent severe outbreaks of these drinking water issues have prompted wider advocacy of a more proactive "source-to-tap" approach, with greater focus on multidisciplinary partnerships among utilities, scientists and management/policy-makers, However, the practical application of this management model is faced with fragmented drainage basins, waterbodies and jurisdictions, and often requires a common issue such as T&O to initiate its development. This paper presents an example of a successful cooperative approach to drinking water management, the Ontario Water Works Research Consorilum (OWWRC), consisting of the six major water utilities drawing water from Western Lake Ontario, scientists from the Canadian and Ontario governments and universities, and several other agencies. Established in 1999 following severe T&O outbreaks, the OWWRC has since operated as a highly effective model, employing a science-based approach to T&O management, supporting research on source-water and treatment issues, public outreach and utility surveys. The paper describes this partnership and summarises the results of an OWWRC T&O survey as one of the significant steps towards source-water characterisation undertaken by this cooperative. [ABSTRACT FROM AUTHOR]

Given their widespread and prolific annual development in the St. Lawrence River (SLR), macrophytes (i,e. submerged aquatic plants) represent large surface areas for biofilm growth and potentially important sites for associated production of taste and odour (T&O) compounds. We therefore evaluated the importance of submerged macrophytes and their associated biofilms for production of T&O compounds, 2-methylisoborneol (MIB) and geosmin (GM), compared with biofilms from adjacent rocks. We also tested the hypothesis that production of these compounds would differ between macrophyte species, based on the premise that they are not inert substrates but directly influence the communities that colonise their surfaces. Samples collected from transects across the SLR between Kingston and Cornwall, ON were dominated by the flat-bladed Vallisneria spp., and the leafed Myriophyllum spicatum, Elodea canadensis, Chara spp., Potamgeton spp., and Ceratophyllum spp. Overall, MIB and GM levels in biofilms ranged widely between samples. Expressed per g dry weight of biofilm, median levels from macrophyte were 50 (range 1-5,000) ng MIB g-1 and 10 (< 1 to 580) ng GM g-1 compared with 50 (range 5-970) ng MIB g-1 and 160 (1-1,600) ng GM g-1 from rocks. Based on non-parametric statistical analysis, levels of GM were higher on a g dry weight basis in biofilms from rocks than macrophytes (P = 0.02), but MIB levels were similar (P = 0.94). However, when normalised for differences in substrate surface area (i.e. ng cm-2), levels of both MIB and GM were higher in biofilms from rocks than from macrophytes (P < 0.01). There were no discemable differences in MIB and GM concentrations from biofilms of different macrophytes based on either g dry weight sample or surface area (P > 0.05). Overlying water (OLW) concentrations ranged between 2-45 ng L-1 for MIB and 5-30 ng L-1 for GM and were not correlated with levels in adjacent biofilms. However, OLW concentrations peaked in shallow, low energy embayments consistent with enhanced production and release of MIB and GM in nearshore areas, The results support our previous work showing the importance of biofilms on various surfaces frocks, macrophytes and zebra mussels) for MIB and GM production in the SLR, but suggest that inert surfaces like rocks are more productive sites per unit surface area than macrophytes. [ABSTRACT FROM AUTHOR]