HUDSON, Fla. — At least a dozen holes have opened up in the ground in Hudson, and efforts are ongoing to figure out what's happening and how to keep property safe. 

Pasco County Emergency Management found 16 depressions between Sylvan Drive and Willow Brook Court in the Beacon Woods community, said Director of Emergency Management Andrew Fossa.

The depressions have grown slightly since the initial inspection on Tuesday, no structures are in danger and there aren't any threats to public safety, he said.

The largest hole is 15-feet-long by 25-feet-wide by 8-feet-deep. It has water in it, and Fossa said it has hit the aquifer.

The holes are on private property -- some are owned by homeowners, some by the homeowners association. The county will work with them to contact their insurance companies.

Two of the holes were on the county right of way, and they have been filled in with sand. It is rare for this many holes to open up at the same place at the same time, Fossa said.

A state geologist or a private contractor will have to determine what caused them.

"I said, 'Woah,' when I saw them, and I keep watching them and I check my own yards and take care of my neighbors,” Pat Johnson said. “They're scared. My friend across the street and her husband are not well and they lose sleep over it, which is a bad thing.” 

There is an active cave system that runs right through the neighborhood, but it is too soon to determine if that's the cause of the holes, Fossa said.

Watch: 10News chief meteorologist Bobby Deskins explains what causes a sinkhole

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