After the flames, wildfires pollute drinking water for years |
When people think about wildfires, they usually think about flames, smoke and evacuations. However, for many communities, some of the most important damage begins after the fire has passed.
Most wildfires leave behind a barren, blackened landscape, and within this changed environment, important impacts can leave their mark. Trees and other vegetation that once slowed rainfall and held soil in place are gone. Ash and burned debris cover the ground. Soil can become more vulnerable to erosion.
Then, the rain comes. When that happens, streams, rivers and water reservoirs receive a sudden pulse of ash, sediment and fire-suppressant chemicals washed off the land. For communities that depend on those waters for drinking water, wildfires can quickly become a long-term water-quality problem.
This risk is often overlooked when governments and communities think about wildfires. Our recent review of 23 studies across 28 watersheds brings together existing knowledge on how wildfire-related contaminants affect water sources.
One of the clearest lessons is that the impacts of wildfire do not stop at the edge of the burn scar. They can travel downstream, into the waters that people rely on every day.
Read more: Why forest loss is making our watersheds leak........