Engineers were back out on Cambria Drive in Williamson County Wednesday, taking a closer look at the cave found underneath the road.
The county said a cave collapse formed a large hole, revealing a 200 foot cavern underneath. Three homes sit on top of it.
KVUE spoke with Jay Banner, geosciences professor at The University of Texas. He said there are an estimated 3,000 caves in Central Texas. We asked him how a hole in the road happens -- revealing a cave underneath.
Banner said it could be a number of reasons. One possibility:
"The process of forming a cave has basically created a large void really close to the surface,” said Banner. “If we're a hundred feet down, that cave's not going to be that big of a factor. But if that cave is forming really close to the surface, then there's just a thin layer of support, between the void underneath."
Banner says caves form here because Central Texas sits on a layer of limestone called the Edwards Aquifer.
"The combination of rain, with carbon dioxide released from soils, makes for a solution that can dissolve limestone," he said. "If you dissolve enough limestone, you make -- start making a small pore, and if you make a pore that's big enough for a person to fit in, then you've made a cave."
Could what happened on Cambria Drive happen elsewhere in Central Texas?
Banner said any karst or cavernous terrain has a possibility of forming more openings.
"Either through human or natural processes," he said.
But he said it is a small chance.
Williamson County said the Cambria Drive cave was a closed cave, and there were no openings where people could reach it.
The county also said a geotechnical report is completed for infrastructure and roadways.
Homeowners have an HOA meeting Thursday night at 6:30 p.m. where they’re expected to hear from the county. It will take place at the Brushy Creek Community Center at 16318 Great Oaks Drive in Round Rock.