Sinkholes in Charlottesville: How They Form and What to Do About It

8/20/2018 (Permalink)

Sinkholes can form in the foundation under just about anything.

Sinkholes can be terrifying; maybe its left over from some primal fear that supernatural powers would rip open the earth and swallow the unworthy. Whatever the cause, it’s unnerving to see a hole suddenly appear in the ground after a storm. But as with everything, the more we can understand it, the less we have reason to fear sinkholes unreasonably.

Recently, a sinkhole opened on Holkham drive in Albemarle County. After a large storm dislodged the sinkhole, it opened through Holkham drive, trapping residents on either side of the hole.

Sinkholes are natural phenomena that can take many years to form. Although it might feel like they just appeared overnight, Mother Nature has actually been working on them for quite a while. This process starts with a foundation material that is porous and can be dissolved or eroded by water. To form a sinkhole, an area also needs a place for water to congregate without a natural place to drain. With these two characteristics present, we’re halfway to a sinkhole!

Once the water is trapped without a natural drainage point, it begins to sink into the porous rock that it’s resting on. Once the water travels through this rock it can erode it or dissolve the rock. It keeps doing this until there is a sinkhole sized cavity resting just underneath the surface of the earth. Once this stage is reached, anything small can cause the sinkhole to collapse. A large storm or flood can easily cause this type of reaction in a potential sinkhole.

It’s interesting to discover these types of phenomena that happen in our own backyards that can be realized with just the right storm, but they are also dangerous and can pose as a real hazard to a community. So, if you see a sinkhole be sure to tape it off way back from the visible edge and stay away from the edge yourself. Then call the first responders.