(KTXL) — The winter storms hitting California prompted warnings of debris flows in areas where wildfires had scorched the land and left it weak against rainfall.
A debris flow, which is a mass of fast-moving materials, can happen on unaffected steep slopes, places where an earthquake has happened and locations with weak or loose rock and soil, but they are much more likely to happen near burn scars, areas where a wildfire recently burned through.
“Areas impacted by fires are particularly prone to debris flows. The burning of vegetation and soil on slopes more than doubles the rate that water will run off into watercourses,” the California Department of Conservation said.
According to the Department, short and intense periods of rain can cause debris flows. It can carry anything from rock, soil, vegetation, and even boulders and trees. They are even strong enough to move cars.
Carrying objects of varying sizes, they can cause loss of life and property damage. Even small debris flows can be hazardous, with the department describing it as “trying to walk through a 3-inch deep mass of wet concrete moving at 30 mph.”
Residents should stay up to date on weather forecasts in the area, not just locally, and listen to warnings from officials, the department said.
“It’s the rain in the mountains that will start the debris flow, even if it’s not raining – or only sprinkling – where you live,” the Department of Conservation said.