Wildfires leave behind charred trees and scorched vegetation that impact the streams and rivers providing drinking water to much of the country, and new studies show that contamination could remain for more than a decade. … After a wildfire sweeps through hillsides and forests, rains carry ash and organic matter into the streams that feed water treatment plants for towns and cities alike. Communities are working to adapt, but it can take years and require stopgap solutions. … Forested watersheds provide water to nearly two-thirds of municipalities in the U.S., according to Carli Brucker, lead author of a University of Colorado Boulder study that assessed wildfire-affected water quality in hundreds of burned basins and compared them to unburned areas.