Understanding the Risks of Mudslides and How to Protect Yourself

The recent heavy rain across the western U.S. has prompted local officials to warn about the potential of mudslides. This threat has been particularly prominent across the recent burn scars left by the devastating January wildfires in Southern California. Here is a primer on mudslides, what makes them so dangerous, and how you can prepare for this fury of Mother Nature.

Understanding the Fury of Mudslides

Mudslides can happen in any U.S. state. A mudslide is a specific type of landslide. While landslides can carry rock, soil, or any kind of flowing debris coming down a slope, a mudslide is defined by its quick-moving nature containing mud. Landslides or mudslides can happen at any time of the year.

The unpredictability of mudslides is just one part of what makes them so dangerous and deadly. Mudslides typically happen when water saturates the sloping ground at a fast clip, usually after periods of heavy rain. Due to this trigger, it is most common to see mudslides during the wet season.

This timing means that mudslides are more likely on the West Coast during the winter and spring months. However, natural events such as earthquakes and volcanic eruptions can also create mudslides.

Mudslides come in two primary forms. The first type is a mudflow, consisting of just water and mud rushing down the slope. Mudflows are generally more shallow in nature, measuring 15 feet deep or less. The second type of mudslide is a debris flow, bringing down mud as well as rocks, branches, and large rocks.

According to the U.S. Centers for Disease Control and Prevention (CDC), mudslides kill about 25 to 50 people per year in the U.S.