Water Quality Data to Support Cumulative Effects Decision-Making in the Mackenzie Valley, Northwest Territories

Freshwater systems have come under increasing stress as a result of anthropogenic activities and climate change. Across Canada’s North, the assessment and management of cumulative effects to freshwater systems remain an enduring challenge to responsible resource management decisions. Recent practice and research indicates a clear need to improve how cumulative effects are assessed and managed, and to bridge the gap between the science conducted inside and outside environmental assessments. Science inside environmental assessment refers to monitoring conducted for environmental assessments and under water license requirements and science outside environmental assessment refers to monitoring conducted for environmental effects monitoring programs. This research examined how environmental monitoring programs in the Mackenzie Valley, Northwest Territories, contribute to the identification, understanding and management of cumulative effects to freshwater systems. The research methods involved a document review to assess the nature of monitoring conducted by project proponents under water licensing requirements as well as the monitoring conducted, and supported, by government agencies for environmental effects monitoring. Semi-structured interviews complemented the review to determine the utility of existing data to develop environmental baselines and to predict cumulative effects. Interviewees included staff from land and water boards, industry proponents, consultants, independent mine oversight boards and various levels of government. Key findings suggest that there are several challenges, including the lack of common understanding of cumulative effects, uncertainty over responsibility for them, degree of participation required among stakeholders and inaccessibility of both government- and proponent-based data. Ultimately, this may be preventing cumulative effects from being assessed, and appropriately managed, in a comprehensive, consistent and systematic manner. While it is evident that a great deal of environmental monitoring is conducted in the Northwest Territories, results indicate it requires a more deliberate approach to ensure that the data collected support cumulative effects assessment and management initiatives at both the local (i.e. project) and more regional scales. These results will both aid in advancing the integration of government- and proponent-based environmental monitoring and be of direct value for regulatory decision-making by land and water boards in the North