Environmental Science
When Rain Turns Burned Ground Into Rivers of Mud
Quick fact
Wildfires can create a water-repellent layer in the soil, drastically reducing infiltration. When rain falls, water runs off rapidly, picking up loose sediment and forming a debris flow.
Why this is interesting
After a wildfire, a gentle rain can suddenly trigger a fast-moving slurry of ash, boulders, and debris. What hidden changes in the soil make these deadly flows possible?