MTPR

Agencies Working Toward Common Selenium Limit For Lake Koocanusa

Nov 1, 2017

The U.S. Geological Survey has released a new modeling framework for collection and analysis of selenium data in Lake Koocanusa.

The framework is designed to organize data collected by different agencies using different protocols, with a long-term goal of helping managers develop a common water quality standard for selenium levels in Lake Koocanusa, which straddles the international border.

Selenium levels have been on the rise in the lake for the past decade due to open-pit coal mining in British Columbia.

Selenium is a naturally-occurring chemical that, in high concentrations, can be harmful to sensitive fish species, like cutthroat and bull trout, burbot and mountain whitefish.

The Montana Department of Environmental Quality considers Lake Koocanusa impaired by selenium.

The USGS modeling framework was funded by the Montana DEQ. The report is available at https://pubs.usgs.gov/of/2017/1130/ofr20171130.pdf

Editor's note: A previous version of this article classified selenium as a heavy metal. Selenium is a naturally occurring chemical element. The article has been changed for accuracy.