NAWQA Upper Snake River Basin Study Unit


The Upper Snake River Basin Study Unit encompasses an area of southeastern Idaho and portions of Wyoming, Utah, and Nevada. It is one of over 40 nationwide study units of the USGS National Water-Quality Assessment (NAWQA) Program. The study unit was selected for its diverse land-use issues. Irigation, grazing, private and commercial development, and other uses pose potential risks to water quality.

Since 1991, the USGS Idaho Water Science Center has led numerous investigations of the basin's surface water, groundwater, and aquatic biological resources to identify the water-quality status and trends. To learn more about these studies, please visit the individual study Web sites listed below or the study unit publications page.

Groundwater Status and Trends

Southern Idaho spring fed by groundwater. Click to go to study Web site.

Problem: There is not a good understanding of groundwater conditions, sources, and transport of contaminants within the study unit.

Approach: Data collection and analysis will continue during cycle 2 of this study. Also, data from the Upper Snake River Basin Study Unit will be applied to National-scale comparison in the NAWQA Western Volcanics study. Go to study Web site

Effects of Nutrient Enrichment on Stream Ecosystems

Snake River marsh area. Click to go to study Web site.

Problem: Elevated nutrient contamination can affect the ecological health of a stream. For example, excessive aquatic plant growth, caused by increased nutrients, can reduce dissolved oxygen which is necessary for other aquatic life.

Approach: Since 2006, the USGS Idaho Water Science Center has collected and analyzed aquatic chemical, physical, and biological samples from within the Upper Snake River Basin Study Unit. Go to study Web site

Initial Interdisciplinary Study

Surface water, groundwater, water quality, biological, and water use data were collected and analyzed during cycle 1 of the NAWQA Program. Go to study Web site