Roman Dial, a professor of biology and mathematics at Alaska Pacific University, first noticed the stark water-quality changes while doing field work in the Brooks Range in 2020. He spent a month with a team of six graduate students, and they could not find adequate drinking 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.”