Water and Suspended Sediment Quality of the Transboundary Reach of the Slave River, Northwest Territories Photo credit: AANDC Water and Suspended Sediment Quality of the Transboundary Reach of the Slave River, Northwest Territories Prepared by: Juanetta Sanderson1, Andrea Czarnecki1 and Derek Faria2 1Water Quality Specialist, 2Hydrologist Water Resources Division Renewable Resources and Environment Directorate NWT Region Aboriginal Affairs and Northern Development Canada Yellowknife, Northwest Territories November 2012 ACKNOWLEDGEMENTS The compilation of this report was only possible with the help of many individuals. We would like to acknowledge our Aboriginal Affairs and Northern Development Canada (AANDC) colleagues: Denise McCann, Bart Blais, Wayne Starling and Ervin Allen who were always willing to help with the fieldwork and Michele Culhane and Laurie McEachern for their contributions to the report. Also, thank you to Shawn Larocque (AANDC) for his excellent maps. Laboratory support and guidance was provided by Shannon Luchka and Deib Birkholz (ALS Laboratories) and Judy Mah and Angelique Ruzindana (Taiga Environmental Laboratory). Data compilation and auditing was done by Caroline Lafontaine (AANDC) and staff of MacDonald Environmental Sciences (MESL). We also want to thank Barry Zajdlik (Zajdlik and Associates) for his support on this project and especially for the long-term water quality temporal trends analyses results. We express our gratitude to Dorothy Lindeman (Environment Canada), Erin Kelly (Government of the Northwest Territories) and Don MacDonald (MESL) for their time and scientific reviews of the report, as well as Robert Jenkins (AANDC), Steve Kokelj (AANDC), Bob Reid (AANDC), Shawne Kokelj (AANDC), Les Swain (TriStar Environmental Consulting) and Dan Peters (Environment Canada) for their constructive reviews. We would like to commend Environment Canada for the long-term operation of the Slave River at Fitzgerald water quality monitoring site. Long-term monitoring is fundamental to begin to understand changes in water quality and forms the basis of many different research and monitoring initiatives. We extend a very special acknowledgement to our former colleague, Wayne Starling, for his long standing dedication to the AANDC transboundary monitoring program and water programs in the South Slave District. And finally, to the residents of the Slave River region for their patience regarding the release of this report and for always impressing upon everyone the importance of this northern river. i EXECUTIVE SUMMARY Introduction This report describes the water and suspended sediment quality conditions in the Slave River at Fort Smith. The status and long-term trends in water quality from the Slave River at Fitzgerald are also examined. Additionally, seasonal flow patterns and long- term temporal hydrological trends for the Slave River at Fitzgerald are assessed. A summary of the geology and upstream activities in the Slave River Catchment is also provided. Current monitoring efforts are assessed and recommendations are made for future monitoring. The Slave River is the largest transboundary river in the Northwest Territories and it is an integral component of the Mackenzie River Basin, contributing approximately 75% of the inflow to Great Slave Lake. Its vast catchment area includes the Peace River, the Athabasca River and Lake Athabasca sub-basins, which extend across the provinces of Alberta, British Columbia and Saskatchewan. The Slave River originates in the northeastern region of Alberta at the confluence of the Peace River and the Rivière des Rochers, the primary outlet channel of Lake Athabasca and the Peace-Athabasca Delta. The Slave River Catchment has experienced increased resource development over the last several decades. Predominant industrial activities include oil and gas developments, oil sands operations, pulp and paper mills, coal and uranium mining, agriculture, and forestry. Further, the W.A.C Bennett Dam, a hydroelectric development on the Peace River in northern British Columbia, exists upstream in the Slave River watershed. As these upstream developments have the potential to affect water resources, Northerners have raised concerns about impacts on the Slave River, and further downstream in the Mackenzie River basin. In addition, climate change may have the potential to influence the Slave River. Concerns and questions about the quality of the water, and ultimately the health of wildlife and people who drink the water, are especially relevant in the North, given the subsistence lifestyle and the close connection to the land still prevalent today among the predominantly Aboriginal population along the Slave River. In conjunction with other monitoring initiatives, this report strives to characterize the water and suspended sediment quality conditions of the Slave River and inform future research. ii The main objectives of this report were to: Provide a general overview of the current state of water quality, suspended sediment quality and flows in the transboundary reach of the Slave River; Determine if water quality and flows have changed over time; Help to address community concerns about metals and organic compounds in the river; Support the development of water quality objectives for transboundary agreements; and; Outline potential areas where the existing Aboriginal Affairs and Northern Development Canada (AANDC) Slave River monitoring program could be improved. It is hoped that the information contained in this report can be used to help make sound decisions and build policies that will ensure the ecological health of this important transboundary river. Combining the results from this study with information generated from other Slave River and Slave River Delta monitoring programs and research will help Northerners gain a better understanding of the health of the Slave River system. Sampling Sites, Media and Parameters Water and suspended sediment quality data for this report were obtained from three long-term sampling sites located on the transboundary reach of the Slave River. Flow data were obtained from the hydrometric (flow) monitoring station operated within this portion of the Slave River. These include: 1. The Slave River at Fort Smith surface water, centrifugate water and suspended sediment quality sampling mid-river site (1990 to present) led by AANDC Water Resources Division. This program is comprised of two parts: a) Slave River Environmental Quality Monitoring Program (SREQMP; 1990- 1995), and b) Follow-Up Study (2000-2010). 2. The Slave River at Fort Smith surface water quality sampling shore site (1982 to present) led by the AANDC Fort Smith District office. iii 3. The Slave River at Fitzgerald surface water quality sampling site (1960 to present) led by Environment Canada. 4. The Slave River at Fitzgerald hydrometric station (1960 to present) led by Environment Canada (Water Survey of Canada). Centrifugate water samples, as well as surface water, were included in the monitoring program to address water quality concerns, to allow comparison with existing guidelines and to help establish water quality objectives for the Slave River. By separating the suspended sediment from the water using the centrifuge, it is possible to study each media type separately. Due to the size and organic content of the suspended sediment in the Slave River, metals and organic compounds tend to attach to these particles and can be carried long distances from their source. To understand the basic chemistry of the water and suspended sediment quality of the Slave River, samples were regularly analyzed for routine parameters, nutrients and major ions. To help address concerns regarding upstream activities, water and suspended sediment samples were also tested for metals and organic compounds such as chlorophenols, organochlorine pesticides, PCBs, dioxins, furans and hydrocarbons. Some of these substances can be natural, but some are known to be associated with upstream development. Evaluation Methods To evaluate the Slave River water and suspended sediment quality data, comparisons to existing guidelines were made and long-term trends in water quality were examined. The water quality data from both Fort Smith and Fitzgerald were compared to the CCME Canadian Water Quality Guidelines for the Protection of Freshwater Aquatic Life (CPFAL). In the absence of CCME CPFAL guidelines for suspended sediment, suspended sediment quality data were compared to the CCME Draft Interim Freshwater Bottom Sediment Quality Guidelines (SQG; CCME, 1999). For those parameters that did not have a national guideline, water quality guidelines developed by the province of British Columbia or bottom sediment guidelines developed by the Ministry of Ontario were used. These guidelines are meant to protect all forms of aquatic life, including the most sensitive life stage of the most sensitive species over the long-term. It should be noted that these are national guidelines and, therefore, may not reflect specific local conditions, especially sediment-laden northern rivers and ecosystems. iv The Slave River at Fitzgerald water quality data were assessed for long-term trends to determine whether water quality conditions have changed over the period of record (annual trends). Trends were also examined separately for each season (spring, summer, fall and winter). As river flow can influence the outcome of water quality trend analyses, the water quality data for each parameter were tested for a relationship with flow. If