This is the original story It was published on High Country News It is part of Climate Desk collaboration.
Many of the once clear streams and rivers found in Arctic Alaska have turned orange-colored and become more acidic. The landscape, which was once undeveloped, now appears as though an industrial mine is in existence for many decades. Scientists are eager to find out why.
Roman Dial is a Professor of Biology and Mathematics at Alaska Pacific University. He first saw the drastic changes in water quality while fieldwork in Brooks Range, 2020. A group of six students from his graduate program accompanied him for a month, but they couldn’t find enough water. “There’s so many streams that are not just stained, they’re so acidic that they curdle your powdered milk,” he said. In others, the water was clear, “but you couldn’t drink it because it had a really weird mineral taste and tang.”
Dial, who has spent the last 40 years exploring the Arctic, was gathering data on climate-change-driven changes in Alaska’s tree line for a project that also includes work from ecologists Patrick Sullivan, director of the Environment and Natural Resources Institute at the University of Alaska Anchorage, and Becky Hewitt, an environmental studies professor at Amherst College. They are now investigating the mysteries surrounding water-quality. “I feel like I’m a grad student all over again in a lab that I don’t know anything about, and I’m fascinated by it,” Dial said.
Most of the rusting waterways are located within some of Alaska’s most remote protected lands: the Arctic National Wildlife Refuge, the Gates of the Arctic National Park and Preserve, the Kobuk Valley National Park, and the Selawik Wildlife Refuge.
It is strikingly visual. “It seems like something’s been broken open or something’s been exposed in a way that has never been exposed before,” Dial said. “All the hardrock geologists who look at these pictures, they’re like, ‘Oh, that looks like acid mine waste.’” But it’s not mine waste. The researchers believe the land caused the rusty appearance of streambanks, rocks, and other structures.
It is believed that the climate is warming, which is leading to permafrost degrading. This releases iron-rich sediments, which oxidize when they come in contact with water. Water may become more acidic due to the possible oxidation of minerals from the soil. Although the research team has begun to identify the causes, it is not yet clear what the implications are. “I think the pH issue”—the acidity of the water—“is truly alarming,” said Hewitt. Although pH is important for many chemical and biotic processes, it has no effect on intricate food webs found in rivers and streams. The research team doesn’t know what could happen to fish, stream bed bugs or plant communities.
The rusting of Alaska’s rivers will also likely have an impact on human communities. Rivers such as the Wulik and Kobuk have been found to be rusting. These rivers also provide drinking water for many Northwest Alaska Native communities. Sullivan stated that if the water quality continues to deteriorate it could affect species which are the primary source of food for Alaska Native residents living a subsistence lifestyle.
