St. George, Utah and Blue Clay
St. George, Utah and Blue Clay – Building On Bad Soil
If you have been around Southern Utah for a while, chances are you are familiar with Blue Clay. And if you have been around for even longer, there is a greater chance you have seen the effects of Blue Clay. This expansive soil has the ability to severely damage roads, building foundations and sidewalks.
The term “Blue Clay” is most closely related to caliche or bentonite soil. It is more of a broad term referring to any one of a number of expansive soils and clays in Southern Utah. Specifically, it refers to a bluish purple layer of clay called the Chinle formation. These clays are made up of ultra fine sediments left by ancient l
akes and rivers, even volcanic ash. Their properties cause them to absorb moisture like a sponge. As they absorb water they expand.
Why is this important? There are two key reasons:
- If you own a home or building in Southern Utah (specifically in St. George, Santa Clara and Washington) your foundation may be at risk and can easily be damaged by the effects of Blue Clay. Especially if it is a newer structure, built in an area that is largely undeveloped.
- The term “Blue Clay” has become somewhat of a buzzword in Southern Utah, it is very common for people to misdiagnose foundation settling problems in Southern Utah, and associate them with Blue Clay, oftentimes it is the first culprit mentioned when a damaged foundation is discovered. It is important to note that, along with Blue Clay, Southern Utah has a high volume of collapsible soils that can often be misdiagnosed as Blue Clay. Collapsible soils can equally cause foundation damage when excess moisture is applied. The Blue Clay is not always the reason.