You water your lawn. You mow your lawn. You may even plant some shrubs and hedges to make things look nice.
And for what? A giant sinkhole to come and devour the whole thing.
At least, that’s what happened to an unidentified homeowner in Des Moines, Iowa, who heard a sound “like thunder” just after midnight on Wednesday -- and saw that a growing hole was swallowing his front yard, local news station KCCI reports.
Officials said the 40-foot deep hole had swallowed a hedge and a tree, and it was still getting bigger by mid-morning Wednesday, according go to WHO-TV.
Some sinkholes occur gradually, over the years. But the fast-moving, dangerous ones that make headlines are known as “cover-collapse” sinkholes, according to National Geographic.
These typically occur in places where the rock below the surface is a material like limestone or carbonate rock, according to the U.S. Geological Survey. Circulating groundwater can dissolve this material, creating underground caverns, until there’s not enough support for the surface layer of land. This suddenly collapsing layer creates the dramatic effect that people see with sinkholes.