Mudslides

A mudslide happens when a large amount of mud, rocks, and dirt slides down a slope. Heavy rain is the most common cause. Mudslides can move very fast and destroy everything in their path. They are most common on steep hills and mountains.

What Causes Mudslides

Heavy rain soaks into the ground and makes the soil very heavy and slippery. When the soil on a hillside gets too heavy and wet, gravity pulls it downhill. Wildfires make mudslides more likely because they burn away plant roots that hold the soil in place.

Staying Safe

People should not build homes on steep, unstable slopes. Planting trees and bushes helps hold soil in place. After wildfires, slopes are extra dangerous because the soil has nothing to hold it. If you hear a rumbling sound during heavy rain near a hillside, move to high ground quickly.

Fun Facts

• Mudslides can travel at speeds of over 35 miles per hour.
• A single mudslide can carry millions of tons of mud and debris.
• Tree roots help prevent mudslides by holding soil in place on hillsides.

Did You Know?

In 1999, a massive mudslide in Venezuela carried so much mud that it changed the shape of the coastline! Heavy rain caused entire mountainsides to collapse.