Abstract
Many northern Canadian water distribution systems operate a significant portion of the year at temperatures less than 10° Celsius (C) and for certain months of the year operate at less than 5° C. Few studies are available which examine the contribution of microbially influenced corrosion (MIC) to deterioration of these systems. Initial investigations into the effects of MIC on northern water distribution systems indicates a diverse population of bacteria and fungi living in these corrosion biofilms. These organisms appeared to have the metabolic capabilities to contribute to the net corrosion process. Sulfate-reducing bacteria were not generally found as the predominant MIC form in these highly aerobic systems. A heterogeneous population of sulfite and thiosulfate-reducers, sulfur oxidizers, iron reducers and iron oxidizers were isolated and characterized. Some of these organisms not only contribute to pipe deterioration, but are also involved with deterioration of potable water quality and may be pathogenic for certain risk groups in the population. The ecology, role and potential health impact of these organisms in low temperature water distribution systems will be discussed.
