| Abstract/Description or Keywords |
The Elk River watershed is located in the southeast corner of British Columbia, and drains 4450 km2 of the Rocky Mountains to the Kootenay River/Lake Koocanusa about 20 km upstream from the border with the United States. The downstream water quality sampling station on the Elk River is located just upstream from the confluence with the Kootenay River/Lake Koocanusa at Highway 93. This assessment is based on up to 38 years of water quality data during 1968-2005. A second station is located upstream at Sparwood. The main human activities in the Elk River watershed are open pit coal mining, forestry, outdoor tourism, and residential and commercial development. The water quality trends identified below have not yet been confirmed by statistical analysis. CONCLUSIONS: • Selenium concentrations continue to show an increasing trend to higher concentrations and generally always exceeded both CCME and B.C. guidelines for the protection of aquatic life. Work is underway to determine whether these high levels are impacting aquatic life in the Elk River. These high values are associated with surface runoff from open pit coal mining. • Fecal coliform concentrations exceeded source water protection guidelines for use of the water with disinfection only. This means that the water should have partial treatment to remove both turbidity and improve the removal of bacteria. • Otherwise, water quality was generally good with only occasional values exceeding guidelines for pH, temperature, phosphorus, several metals, dissolved organic carbon, and true colour. In cases where total metal concentrations exceeded guideline values, these were generally correlated with higher turbidity concentrations, meaning that the metals were likely in particulate form and not biologically available. RECOMMENDATIONS: We recommend monitoring be continued for the Elk River near Elko since selenium continues to increase and the success of any management steps undertaken can be tracked at this site. Water quality indicators that are important for future monitoring are: • flow, water temperature, specific conductivity, pH, turbidity, nutrients, and dissolved oxygen, • appropriate forms of metals for comparison to their respective guidelines, and • other variables related to drinking water such as colour. |
