SPRING HILL — When Micki Bernardo heard a boom in the middle of the night a couple of months ago, she thought someone was breaking into her home. She never found the source.
When it happened a month later, she remembered the cracks she had noticed around her pool and patio walls. She thought of several neighbors who had dealt with sinkhole problems.
On Wednesday, the day before a crew of engineers showed up to check the stability of the ground under the ranch home she has owned since 1994, a gaping sinkhole swallowed a portion of the home of Jim and Joan Bates two blocks away.
The jarring scene at the house on Orchard Park Drive served as a stark reminder for Bernardo and others that sinkholes are a part of life in west-central Florida. Residents who flocked to the house — in a neighborhood that has seen numerous sinkholes in recent years — couldn't help but question their own vulnerability.
Florida is on the verge of its annual sinkhole season in late spring and early summer, and this year could see more activity because of the effects of three years of drought, geologists say.
Water in the aquifer supports layers of clay and sand on top of limerock, said Tony Gilboy, a geologist with the Southwest Florida Water Management District. That buoyancy effect disappears when levels in the aquifer drop, Gilboy said. After many months of drought, aquifer levels in the district's northern region were more than a foot and a half below the normal range last week.
"There's no question that, because of the cumulative effects, it certainly plays a significant role," Gilboy said.
The increased groundwater pumping as a result of development makes the problem worse, said Rick Green, a geologist with the Florida Geological Survey.
Then when the summer rains return, the added weight on top of the soil and clay, plus the added lubrication of the soils, can also accelerate the process, Green said.
Geological experts say the entire Tampa Bay area is vulnerable to sinkhole activity, particularly Hernando and Pasco counties because of the abundance of limerock beneath the surface.
Homeowners' insurance rates in Hernando are about 50 percent higher with sinkhole coverage, said Danielle Healis, an agent with Killingsworth Insurance in Brooksville.
That makes it tempting for homeowners to take advantage of a 2007 state law that allows policyholders to opt out of sinkhole coverage. Catastrophic damage caused by sinkholes like the one that devoured the Bateses' home is still covered, however.
That may be, but Angel Quis said Thursday he isn't taking chances. Quis lives a couple of blocks from Jim and Joan Bates and says their sinkhole only affirmed his decision.
"You'd have to be crazy not to have (insurance coverage)," he said.
Anne Marie DeMarco, who lives next door to the Bateses with her husband, Jim, said she was devastated.
"It's just too close for comfort," she said.
The DeMarcos said they already have had the ground underneath their home tested for voids that can lead to sinkholes. They declined to say if there were any troubling signs.
The Bates family had done the same, and engineering crews were there Wednesday afternoon pumping concrete into voids when the house began to sink. No one was home, and construction workers freed their three dogs.
Not all of the Bateses' neighbors were on edge, however.
As he stood along the yellow police tape and surveyed the home's damage, Bob Grabowski shrugged off the possible threat under his house a block away.
"If it's going to happen, it's going to happen," Grabowski said.
On Thursday, Jim and Joan Bates were still coming to terms with the turmoil.
They spent a "rough night" Wednesday in a Weeki Wachee hotel, with "lots of tossing and turning," Jim Bates said. "You just keep picturing the house in your mind."
Ignoring the advice of emergency officials, Bates and Dan Pardo, one of the couple's three sons, dashed into the house several times Thursday to grab keepsakes, valuables and important documents.
Joan Bates said they will have to hire professionals to try to get the rest of their belongings. After that, the bulldozer will come. Jim Bates says he wants to rebuild in the same spot; Joan says she's not so sure.
The couple praised the responsiveness of their insurance carrier and said they felt fortunate no one was inside. Still, the loss of the home Joan Bates has owned for 22 years was tough to take.
"I can appreciate people who have gone through disasters now," she said. "Believe me, I can sympathize."
Times staff writer Barbara Behrendt contributed to this report. Tony Marrero can be reached at firstname.lastname@example.org or (352) 848-1431.