The United States and Canada have agreed to launch a probe into a long-running cross-border dispute involving pollution from coal mines in British Columbia flowing into American waters.

The two governments are to look for ways to reduce contamination from the Elk Valley in B.C. that flows into a reservoir straddling the border and into U.S. rivers, an issue that has festered for a decade. 

The agreement involves both national governments, the states of Montana and Idaho, British Columbia and six Indigenous communities on both sides of the border.

It creates an advisory body that has two years to come up with ways for the mines to reduce their releases of selenium, an element toxic to fish. 

The agreement comes after years of complaints from American officials, including senators, the State Department and the Environmental Protection Agency.

Prime Minister Justin Trudeau and President Joe Biden had promised movement on the issue by last summer.

This report by The Canadian Press was first published March 11, 2024.

The Canadian Press