Understanding the Science Behind Sinkholes
A sinkhole has the potential to damage structures and the land, ultimately decreasing a property's value. Sinkholes can also raise the risk of trip-and-fall accidents and contaminate local groundwater. It's important to understand how sinkholes form, know what warning signs to watch for, and be prepared to take action if this issue arises on your property.
What Is a Sinkhole?
Before evaluating the risk of a sinkhole formation, let’s look at what causes this phenomenon. A sinkhole is a depression in the ground that forms as water dissolves surface rock in a particular area. In most cases, sinkholes occur after heavy rainfall. Over time, rainwater erodes the surface rock beneath the soil. Moisture erosion forms cracks and joints in the underlying limestone. As water gathers in those crevices, the limestone separates into smaller pieces. Eventually, the rock becomes unstable, allowing more water and soil to seep in, resulting in a sinkhole.
Where Do Sinkholes Usually Form?
Sinkholes can form in various locations, especially in karst terrain regions. A karst develops from dissolving soluble rocks like limestone, dolomite, or gypsum. Here are some of the areas most vulnerable to sinkhole formation:
- Newly built residential or commercial developments
- Roadway construction zones
- Artificial ponds or other surface water bodies
- Regions that are prone to either rainfall or droughts
- Areas with a low water table due to wells
When you build a structure over the soil in any of these conditions, the extra weight increases the potential for a sinkhole. While excessive moisture often causes a sinkhole, minimal rainfall can also be a risk factor. In a drought, more water is drawn from the underground water table to supply residential or commercial buildings. Over time, this repetitive action can result in a limestone collapse, causing a sinkhole to develop.
How to Detect a Sinkhole on Your Property
Now that you know what causes a sinkhole, let’s examine how to spot the visible signs of a sinkhole on your property. The earlier you can detect this issue, the easier it will be to prevent severe damage. Here are six common signs of sinkhole formation:
- Structural cracks in the floor or walls
- Brown- or gray-colored well water
- Doors or windows that will not fully close
- Nearby foliage that wilts or dies
- Circular crack patterns in the ground
- Formation of gullies or bare soil
If you notice any of these potential red flags, contact a professional water and bioremediation service to help verify and treat the presence of a sinkhole.
What to Do If You Suspect a Sinkhole
When repairing a sinkhole, you’ll want to seal the hole without expanding it further. Also, be sure to monitor utilities in surrounding areas. If the sinkhole exposes electrical lines, plumbing systems, or other underground equipment, contact your local utility provider immediately to mitigate safety hazards.
Next, use dry-mix concrete or a pre-made concrete plug to form a sinkhole base. This concrete layer will replace the limestone and reinforce the soil. After creating that concrete base, mix the topsoil with clayey sand, then fill the sinkhole with this mixture to form a solid barrier against moisture. Use regular sand in a pinch if clayey sand is unavailable at your local home improvement or landscaping store.
Protect Your Property from the Threat of Sinkholes
Sinkholes can cause significant damage to property and the surrounding area, but addressing the underlying issue promptly can prevent major structural issues. Recognizing the warning signs of a potential sinkhole and promptly repairing the problem can make a significant difference for your property.