Question: Why do mudslides occur and how do they relate to soil?
Answer: As explained in the last Soils Matter post, in order to have a strong foundation for a house or a building, the soil must also be stable and strong.
A mudslide (or landslide) consists of mud and other earth materials that fall down a slope, usually after a period of heavy rain. When buildings balance on soils that cannot effectively capture and react to precipitation, mudslides may occur. The weight of the water and the steep incline push the mud and dirt downhill. Mudslides can happen quickly or slowly. Flash mudslides, where heavy, watery dirt falls suddenly without warning, are the most dangerous.
Mudslides can happen in all 50 states, but there are certain places where mudslides are more prone to happen. For example, on the West Coast, states like California, Washington, and Oregon see more mudslides than other states because of their hilly terrain. Lands altered by humans or wildfire are also more at risk for mudslides.
If you are worried about a mudslide because you live near hilly terrain, contact your local authorities to see if mudslides or other debris flows have occurred in your area before. Experts also recommend making an evacuation plan for your home or business. If a mudslide occurs without warning, make every effort to get out of your home or office building. Attempt to go to higher ground, and away from the path of debris flow. The higher up a hill you are, the less likely it will be that you sustain injuries from a mudslide.
-Answered by: Larry F. Baldwin, CPSS / NCLSS, Land Management Group, Inc.
To view SSSA’s video, Soils Support Buildings and Infrastructure, visit https://www.youtube.com/watch?v=zJi-73qeE-0
More educational materials can be found on various SSSA websites:
http://soils4teachers.org/ (K-12 Lesson Plans and Activities)
http://soils4kids.org (Just for kids!)
http://soils.org/iys (International Year of Soils, with a coloring book and monthly ideas for teachers and scientists!)
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