Raging wildfires and 'burn scars' threaten the West's drinking water

This is a Kaiser Health News story.

Colorado saw its worst fire season last year, with the three largest fires in state history and more than 600,000 acres burned. But some of the effects didn’t appear until this July, when heavy rain pushed sediment from damaged forests down mountainsides, causing mudslides that shut down sections of Interstate 70 for almost two weeks.

Immense quantities of sediment choked the rivers that supply most of the state’s water. In western Colorado’s Glenwood Springs, the water became so murky that the town twice had to shut off the valves that pump water from nearby rivers to avoid overwhelming its filtration system. City managers sent alerts to the town’s 10,000 residents, telling them to minimize water use until the sediment moved downstream.

Wildfires and their lasting effects are becoming a way of life in the West as climate change and management practices cause fires to increase in number, intensity and acreage burned, while extending the length of the fire season. In “burn scars,” where fires decimated forest systems that held soil in place, an increase in droughts followed by heavy rainfall poses a different kind of threat to the water supplies that are essential to the health of communities.