While spring in Illinois can bring well-known weather issues such as tornadoes and floods, the season can bring another difficult disaster to expect.

Sinkholes can be a dangerous natural phenomenon — one was recently discovered north of Marion, one killed a Florida man Feb. 28 and one nearly swallowed a golfer March 8 at the Annbriar Golf Club in Waterloo. They occur when holes in the earth widen over thousands of years from cracks in two- to three-feet-wide gaps. Glacial sediments and silt sitting on top of the sinkhole fall into the crack and form a void underground that make its way to the surface where bedrock collapses and instantly creates a hole in the ground.

Sam Panno, a senior geochemist with the Illinois State Geological Survey, said spring is the perfect time of year for sinkholes to appear because rain shifts the ground enough to cause sinking.

“The rain changes the environment underground, and water starts moving through crevices and starts to erode the soil above, where the soil meets the bedrock, and you get the erosion that initiates a sinkhole,” Panno said.

Sam Spearing, mining and mineral resource engineering interim chair and associate professor, said sinkholes can naturally occur but can also be formed through structural issues.

“Sinkholes (can) be man-made accidents, like water pipes bursting and eroding a hole away, or the space between pillars in old mines collapsing in and creating a sinkhole,” Spearing said.

Panno said it is possible to locate a sinkhole before they form. However, he said it is difficult to predict where one might develop because they usually form in a matter of hours or days.

“Although you can’t find them, the best way to avoid a sinkhole, if you live somewhere that usually has them, is to avoid running excess water into another sinkhole in the area,” he said.

Draining excess water from personal property into other hidden sinkholes could activate the erosion process again and cause more sinkholes to occur, he said.

Spearing said there is no permanent answer for sinkhole prevention, but there are ways people can help cover already existing problems. The ground must be reconsolidated to fix them, he said, typically by using compacted aggregate waste such as top soil or broken stone to seal the hole.

Geology professor Eric Ferre said people often try to fill sinkholes with whatever they want and assume it will be enough to prevent another collapse.

“Sinkholes are often used as dumping sites where people put whatever they want, like a TV, refrigerator or old batteries,” he said. “We find … strange things in sinkholes every once in a while. It is like an archeological dig. The deeper you go, the older the stuff you find.”

However, Ferre said it is important that people realize sinkholes are a vulnerable spot for ground water to collect over time. Harmful chemicals are more likely to enter fresh groundwater when people dump their waste in them, he said.

“It is a serious environmental concern, probably a bigger issue right now than the subject of sinkhole collapses,” he said.

While sinkholes have occurred nationwide, Panno said he has seen his fair share of sinkholes in southern Illinois. Much of Carterville was mined years ago, and the digging created sinkholes. The damage caused by collapsing sinkholes can be devastating for property owners, he said.