Alaska’s Arctic Waterways Are Turning a Foreboding Orange

The story was first published on High Country News.

Dozens of once crystal-clear streams and rivers are now running bright orange and cloudy, and some of them are becoming more acidic. Scientists want to know why the landscape now looks like an industrial mine.

Roman Dial, a professor of biology and mathematics at Alaska Pacific University, first noticed the change in water quality while doing field work in 2020. He spent a month with a group of graduate students and they couldn't find enough water. He said that there are so many streams that are acidic that powdered milk can't make it. The water in some places was clear, but it had a weird mineral taste.

Dial was gathering data on climate change-driven changes in Alaska's tree line for a project that also included work from Patrick Sullivan, director of the Environment and Natural Resources Institute. The team is trying to understand the water quality. Dial said that he was fascinated by the lab and felt like he was a graduate student again.

Some of Alaska's most remote protected lands are where most of the rusty waterways are located.

The phenomenon is stunningly beautiful. It seems like something has been broken open or exposed in a way that hasn't been done before. The hardrock geologists look at the pictures and think it's acid mine waste. It isn't my waste. The rusty coating on rocks and streambanks is from the land.

Climate warming is thought to be the cause of underlying permafrost degrading. They oxidize and turn a rusty orange color when they hit running water and open air. It is possible that the oxidation of minerals in the soil is making the water more acidic. In order to better explain the consequences, the research team needs to identify the cause. The acidity of the water is really alarming. The impact on the intricate food webs that exist in the waterways are not known. The research team doesn't know what changes will look like.

Human communities are likely to be affected by the aging of Alaska's rivers. Many Alaska Native communities in Northwest Alaska get their drinking water from the rivers. Sullivan is concerned about how the water quality will affect the species that serve as a main source of food for Alaska Natives.