Coeur d'Alene Lake Water Quality

Science Center Objects

The mining district in the South Fork Coeur d’Alene River valley was among the Nation’s largest producers of silver, lead, zinc, and other metals from the 1880s to the 1980s. These activities have produced large quantities of waste material that contain environmentally hazardous contaminants such as cadmium, lead, and zinc. Much of this material has been discharged directly to or washed into the South Fork Coeur d’Alene River and its tributaries, and continues to make its way to Coeur d’Alene Lake and beyond.

We conducted two large-scale studies of the lake (1991-92 and 2004-06) to understand the complex interaction of physical, chemical, and biological processes in the lake and the resulting water-quality conditions. We've assessed temporal and spatial differences and identified potential changes and trends in lake water quality over time. The insights gained from these studies can be used by decision-makers to manage Coeur d’Alene Lake water quality and contaminants in the basin.

Our studies resulted in many reports that focused on particular scientific questions and areas of the lake. Please see the list of reports below for key findings related to each area of interest.