By Anumita Kaur, The Washington PostAn orange tributary of the Kugururok River on July 17, 2023, in Alaska. Orange streams are increasingly common in the Brooks Range of northern Alaska. , and it could have disastrous, cascading consequences on the state’s ecology and rural communities, researchers said in a study last week.
Researchers said the changes could be the result of melting permafrost — propelled by climbing temperatures — which released naturally occurring sulfide minerals into the water. When these minerals, including iron, slip into the water, they react with oxygen and effectively rust, turning clear streams bright orange.
Researchers across USGS, NPS and UC Davis ultimately identified 75 rivers for the study that had turned orange to varying degrees and intensities, collecting 23 upstream- and downstream-water samples. Waterways included the Salmon, Agashashok and Kugururok rivers.Some ran a murky and cloudy orange; others were bright. All suggested that something was wrong.
There are two major implications that researchers are concerned about, Poulin said. “The first is ecological: Some of the metals being released can be acutely toxic to organisms.”survival, he said. “Subsistence fishing is recognized as a major part of their culture and lifestyle,” and compromised rivers would have cascading effects on rural and Indigenous communities’ fishing practices.
“It’s really disturbing to see this kind of rapid change associated with climate change,” he said. “It’s a call to action for the entire state.”