With 174 active wildfires burning across Canada, several U.S. states are under air quality alerts due to the traveling smoke from these flames.

Smoke from Canadian wildfires is engulfing much of the eastern and central United States and and is expected to continue for days.

There were no air quality alerts across the U.S. early Friday, following a flurry of warnings partly linked to wildfires in Canada.

Negotiations over the Columbia River basin could affect the environment in Canada and electrical generation and flood control in the United States. Negotiations of a 60-year-old treaty between ...

Air quality alerts remain in effect June 6 for Southeast Michigan 00:54. An air quality map shows conditions improving across the United States on Friday as smoke from the Canadian wildfires ...

After the slow start, the United States and Canada announced the rough outlines of agreement last summer that reflected a reality far different from what the treaty writers in the 1960s anticipated.