Orange instead of crystal clear – waterways in Arctic Alaska
Streams and rivers in the undeveloped Arctic of Alaska are actually crystal clear and provide the best drinking water. But for some time now, streams in the remote north of Alaska have been turning orange and becoming increasingly turbid. At first glance, one might suspect acidic mine tailings to be the cause. But researchers blame climate change for the discoloration and clouding of the waters.
The change in water quality first caught the eye of Roman Diel, professor of biology and mathematics at Alaska Pacific University, in 2020 when he was in the Brooks Range with graduate students for fieldwork and they couldn’t find enough clean drinking water. “There are so many streams that are not only polluted, but so acidic that they curdle powdered milk,” he tells High Country News. Others carried clear water, but it had a strange mineral taint.
Dial has been conducting research in the Arctic for 40 years and, along with ecologists Patrick Sullivan, director of the Environment and Natural Resources Institute at the University of Alaska Anchorage, and Becky Hewitt, professor of environmental studies at Amherst College, has been collecting data on climate change-induced changes in Alaska’s tree line. But now the team is trying to figure out what is causing the changes in water quality in streams and rivers, most of which are in some of Alaska’s most remote protected areas: the Arctic National Wildlife Refuge, Gates of the Arctic National Park and Preserve, Kobuk Valley National Park and Selawik Wildlife Refuge.
The research team suspects that rising temperatures are thawing the permafrost, releasing iron-rich sediments. On contact with flowing water and air, these oxidize and turn rusty red. This could also lower the pH of the water, making it more acidic, and have implications for the complex food webs in these waters. Exactly what consequences the altered pH will have for fish, bugs and plant communities is not yet clear to the research team.
The altered water quality can also have far-reaching consequences for Alaska Natives who live on subsistence. Indeed, drinking water sources such as the Kobuk and Wulik rivers are also impaired. In addition, according to Sullivan, one of the biggest concerns is how further degradation of water quality will affect the species that Native people use as a food source.
“We’re always worried about the drinking water,” says Millie Hawley, tribal administrator in the community of Kivalina on the Wulik River. Year-round residents fish trout from the river and have observed that the water has become increasingly murky in recent years.
The research team assumes that this phenomenon has already occurred in the past, but at a much slower rate than now in times of man-made climate change.
The researchers also suspect that not only high temperatures – particularly in the summers of 2019 and 2020 – but also unusually large amounts of snow in subsequent winters have hurt permafrost. “Snow is an excellent insulator for soils and can greatly enhance permafrost thaw,” Sullivan said.
The team is not yet sure whether the discoloration of rivers and streams coincides only with unusually warm seasons and a thick snowpack. Only time will tell how long the phenomenon lasts.
Julia Hager, PolarJournal
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