Pumping May Be To Blame For Plant City Area Sinkholes, Official Says

Heavy groundwater pumping to irrigate crops during recent cold snaps might be to blame for a half-dozen recent sinkholes that have closed roads in the Plant City area, Hillsborough County officials say.

The latest two sinkholes were reported Wednesday morning, said county spokesman Steve Valdez. He said all are within about a four-mile radius in the Plant City area, home to many strawberry fields.

Taking into account the geographic area of the sinkholes and the heavy pumping strawberry growers historically rely upon during a freeze, agricultural activities are likely to blame, Valdez said. The first sinkhole was reported Jan. 30, the day after the first in a series of sub-freezing mornings, he said.

Sinkholes damaging county roads have been reported at: 1106 Whitelaw Road; 3706 Moore Lake Road; 3480 Gallagher Road; 14310 Sydney Road; 3201 Lone Oak Road; and 4173 Drawdy Road.

After closing the damaged road, county public works employees examine the indentation and cover it with sand to observe whether it drifts deeper into the hole, Valdez said. "You have make sure the settlement has stabilized," he said, as a seemingly small hole could be an indication of a much larger void, capped by the roadway's asphalt.

Ultimately, all the holes will be backfilled with dirt, sealed and the roadway resurfaced.

"I have no idea what this is going to end up costing us, either," said Valdez. "If all are confirmed as sinkholes and have voids, it could be in excess of $375,000."

No county roads outside the Plant City area have been impacted by sinkholes this year, Valdez said.
The county tracks sinkholes impacting county roads and other county property, but not those occurring on private property.

Collapse sinkholes, the most common type in Florida, occur suddenly and are frequently triggered by fluctuations in the groundwater level, geologists say.

Plant City officials are also looking at a sinkhole that has opened under a driveway at a home at 3221 Azalea Blossom Drive. The sinkhole just off Trapnell Road has stranded a car in the driveway.