Rusting rivers

The phenomenon known as “rusting rivers” happens when once-clear streams release highly acidic and metal-laden water, which pose a direct threat to fish and vegetation. It’s happening throughout Alaska’s Brooks Range.

“We noticed that the stream had changed color from this pristine, clear water to a bright orange,” O’Donnell said. “There were no fish — all the fish had left.”

In the Northwest Arctic, runoff from permafrost thaw is turning rivers and streams a rusty orange color, releasing extremely acidic water, and creating dead zones for plants and animals