| Abstract/Description or Keywords |
The Columbia River watershed is located in the southeast corner of British Columbia, and at Nicholson drains 6660 km2 of the headwaters of the river, with the Rocky Mountains to the east and the Purcell Mountains to the west. The river flows in the Rocky Mountain Trench and is used for drinking water, irrigation and industry and supports populations of cutthroat, rainbow, bull, and eastern trout and whitefish. Cirque glaciers in the high Purcells and Rockies drain to the Columbia River and the glacial silt imparts a gray, muddy colour to the river at times.This assessment is based on up to four years of water quality data collected during 2003-2006. The main human activities in the Columbia River watershed are forestry, outdoor tourism, and residential and commercial development. CONCLUSIONS: • The data base is of too short a duration to detect any long-term trends of increasing or decreasing concentrations that may be present. • Several metals that exceeded guidelines on occasion had higher concentrations that correlated with high turbidity levels. At those times, metals were likely in particulate form and not biologically available. Such metals included aluminum, cadmium, chromium, iron, lead and zinc. RECOMMENDATIONS: We recommend monitoring be continued for the Columbia River at Nicholson since it serves as an upstream station for the lower Columbia River sites. It is the only site monitored on the Columbia River that does not have flows regulated by dams and thus reflects the natural pattern of concentrations relative to solids concentrations. 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. |
