Some researchers thought her team wouldn't even be able to detect an impact from the fires because the Athabasca River was already looking like tea before the fires. Heavy rains tend to send hot fudge-looking runoff from the land into the river, making it look like chocolate milk, she said. Arriving after the fires, Emelko said she could see that hot fudge-looking flow enter the Athabasca's waters as ash, likely carrying nutrients like phosphorous and carbon, made the water supply challenging for treatment processes. "Those [workers] were living in the water treatment plant, working hard to make sure that people could return to their homes and at least have safe water to drink," Emelko told Day 6 host Brent Bambury.