LAND O’ LAKES, Fla. — Ahas stopped growing, and officials said they would monitor it over the weekend before determining when cleanup can begin.
The hole has been stagnant since Friday afternoon, said Kevin Guthrie, Pasco County’s assistant administrator for public safety. He confirmed that the hole, which is 250 feet wide and 50 feet deep, is the largest in three decades in the county, which has a history of sinkholes.
“Our hearts and thoughts go out to everyone in this community,” Pasco County Sheriff Chris Nocco said, according to CBS affiliate WTSP-TV. “This is Mother Nature and we don’t know where it’s going to go.”
Dramatic video showed the home in Land O’ Lakes, north of Tampa, collapsing into the hole Friday morning. It quickly engulfed one home and a boat and then consumed about 80 percent of another home.
Guthrie said 11 homes in all have been affected. A third home lost about 45 feet of driveway and a septic tank.
All three homeowners had insurance, he added. No injuries have been reported.
State geologists and environmental officials will continue to monitor the sinkhole over the weekend before determining when cleanup can begin.
The scene is being considered a hazardous materials incident because of possible septic tank issues and building debris. Guthrie said that chemicals from at least three septic tanks are in the sinkhole.
Cleanup will likely take weeks while repairs to the road and the damaged lots will take months.
Jared Hill of the Pasco County Sheriff’s office said that deputies helped one of the homeowners retrieve some items on Friday night and that they would help with the other home on Saturday.
“This is a very catastrophic event,” Hill said. “One resident was going to go on vacation and now that has changed. Now they are trying to get as much out as they can so they can move on with their lives.”
County property records show there was a sinkhole at the property where the first house was swallowed up, and that it had been stabilized in 2014. The home was sold in 2015, according to records. Messages left for its owner were not immediately returned Friday.
Sinkholes are stabilized by boring holes into the ground and injecting concrete.
Records also show a sinkhole was stabilized at the partially destroyed home in 2007. Two sisters renting that home with four other family members said they had left the house early Friday and returned to see their neighbor’s home falling into the sinkhole.
The Tampa Bay Times reported that Edilia and Theresa Villa and their relatives had time to retrieve important documents and six dogs from their house before officials declared it unsafe. Theresa Villa’s 15-year-old daughter, Thalia Chapman, told the newspaper the family moved into the home after arriving from Cuba about a decade ago.
Officials said Duke Energy has restored power to the neighborhood.
SOURCE & CREDITS: CBS NEWS
What are sinkholes?
Authorities have not said what caused this particular Florida sinkhole. Pasco County records show the houses were built on the site of a sinkhole, Guthrie said.
Sinkholes often form when acidic rainwater dissolves limestone or similar rock beneath the soil, leaving a large void that collapses when it’s no longer able to support the weight of what’s above it, whether an open field, a road or a house.
Sinkholes are particularly common in Florida, which rests on a nearly unbroken bed of limestone, according to the Florida Sinkhole Research Institute. They often develop in Central Florida, including the Tampa area.
Every once in a while, you’ll see a news story about a sinkhole that suddenly opens up and causes quite a stir. Although it may seem like these are rare oddities, sinkholes are actually quite common all over the world.
Sinkholes go by many names around the world, including sinks, shake holes, swallow holes, swallets, dolines, and cenotes. Although they may be called by different names, they have similar causes.
Sinkholes are depressions or holes in the Earth’s surface caused by natural karst processes. Karst processes occur when water and chemicals dissolve carbonate rocks, such as limestone, to form sinkholes and caves.
For example, one common scenario involves the gradual erosion of bedrock by ground water that percolates down through cracks in the bedrock. As the rock erodes and weakens, spaces and caverns develop underground.
The land above the developing spaces usually remains intact until the rock underneath can no longer support it. When the underground spaces grow large enough, a sudden collapse of the surface land above can occur.
This is what happens when a sinkhole “suddenly” opens up. Of course, the underlying processes have been going on for some time.
Sinkholes can also be caused by human factors. For example, man-made mines that are no longer used occasionally cause collapses. Water and sewer pipes that break can also sometimes lead to the formation of sinkholes if they create underground flows that speed the process of erosion.
Sinkholes range in size from 3 feet to over 2,000 feet (.9 meters to 609 meters) — both in width and depth. The largest known sinkhole in the world is in China. Called the Xiaozhai tiankeng, it is almost 2,200 feet (670 meters) deep!
Sinkholes that form in coral reefs or islands can often be very deep and filled with water. They’re known as blue holes, because of the deep blue color of the water in these holes. Blue holes often become popular spots for divers to explore.
Not all holes that suddenly open up in the ground are sinkholes, though. In May 2010, a huge hole opened up suddenly in Guatemala City, swallowing a three-story building and a house. Although news reports called this hole a “sinkhole,” it was actually something scientists call a “piping pseudokarst.”
Because there is no carbonate rock under Guatemala City, the hole couldn’t be caused by karst processes and thus technically couldn’t be defined as a sinkhole. Instead, the hole was caused by the collapse of large cavities that had developed over time in the thick volcanic ash deposits that exist under Guatemala City.