Idaho's Kootenai River, which also runs through Montana and British Columbia, has made an environmental group's list of the 10 most endangered rivers in the United States.
American Rivers, in its annual report on endangered rivers, said outdated water management continues to plague U.S. waterways.
In particular, environmentalists point to open-pit coal mining as the Kootenai River's greatest threat.
"The quality of the water and the species that depend on it are threatened by five open-pit coal mines along a tributary in British Columbia," according to a statement from American Rivers, which is calling on the U.S. State Department to work with Canada "to halt the mining until impact studies can be done."
The Kootenai provides habitat for grizzly bear and woodland caribou, in addition to "several rare and threatened species of fish," according to American Rivers.
Topping this year's list of most endangered U.S. rivers was the Colorado River, followed by Georgia's Flint River and the San Saba River in Texas.