A water main break caused a sinkhole to form near the University of Minnesota over the weekend, and it nearly swallowed a car.
The water main broke near Eighth Street Southeast, not far from the U of M campus, KSTP says.
The front end of the vehicle was submerged into the water-filled hole, while the trunk of the vehicle stayed above water.
It may take a few days to fix the road, Matt Lindstrom, a communications specialist with the city, told BringMeTheNews. The city's sewer department needs to make repairs to the storm drain before a temporary repair can be made and the road reopens, he said.
The science behind sinkholes
Sinkholes are depressions in the ground that open up suddenly, either because of human activity or naturally due to an area's topography, AccuWeather says.
They frequently happen in areas with karst topography – a region underlain by soluble bedrock, like limestone, according to the University of Minnesota.
Over time, water dissolves the limestone and the ground above eventually becomes unstable and collapses, National Geographic says.
This happens a lot in Florida, Texas, Alabama, Missouri, Kentucky, Tennessee and Pennsylvania, the United States Geological Survey says.
But Minnesota is actually home to the sinkhole capital of the United States. Fountain, located in Fillmore County, has billed itself as the "sinkhole capital of the U.S." for more than 25 years – the karst topography in the region has led to the formation of more than 10,000 sinkholes, WCCO reported.
Sinkholes can form due to other circumstances as well, the USGS notes. Collapses can happen above old mines, from leaky faucets, or when sewers give way – anytime underlying soil is removed (through mining or construction), the soil on the surface can collapse.
They can also form due to pressure from above the soil, the American Chemical Society notes. With some sinkholes, the soil underneath is not strong enough to support the weight of water above it. That's why sinkholes can form during heavy rainstorms or when a water main breaks.
Human activity is likely the reason the number of sinkholes is increasing in populated areas, AccuWeather says.