I-4 sinkhole repairs cost $300,000

State highway officials say that repairing a depression in Interstate 4 near Plant City last week and a sinkhole on a nearby entrance ramp cost taxpayers about $300,000.

The depression on the interstate was thought to have been caused by a lowered aquifer level that was the result of a weeklong pumping spree by the area's strawberry farmers during sub-freezing weather. The hole measured 24 feet across and sank the pavement about 2 inches.

Sinkholes and ground depressions have plagued the Plant City area for two weeks. A depression near Trapnell Elementary School sent more than 500 students to other schools Wednesday until the problem is fixed.

Work crews were doing test borings Wednesday at Trapnell, and there was no indication when the school might open. The void "appears to be pretty deep," and crews haven't started trying to fill it, school district spokeswoman Linda Cobbe said.

The cavity had not developed into a sinkhole but was thought to be 80 to 100 feet deep.

The Trapnell students' first day at Strawberry Crest High School and Bailey Elementary went smoothly, Cobbe said. Some Strawberry Crest students made signs by hand to welcome the students to their campus.

Last week, Florida Highway Patrol troopers shut down three eastbound lanes of I-4 for four days, diverting traffic to two alternate routes through Plant City.

To complicate the flow of traffic, U.S. 92, one of the detour routes, was shut down for a brief time because of cracks in the pavement. That proved not to be a depression or sinkhole but just a shift in the bed of the road.

The cost of that fix was not included in the $300,000 figure, said Lori Buck, spokeswoman for the Florida Department of Transportation. Included was the repair work on the Alexander Street entrance ramp to westbound I-4, she said.

For four days, work crews and engineers worked around-the-clock to fix the interstate, eventually pouring 800 cubic yards - 80 truckloads - of grout into five holes drilled around the depression. The grout disappeared into the seemingly bottomless pits, but on Friday, the holes filled up.

On Friday afternoon, crews paved over the depression, and on Friday night, the highway's eastbound lanes opened.

DOT officials have figured the cost but haven't quite figured who will pay. The state will pay the contractor who did the work, and it is examining the possibility of getting reimbursements from the federal government.

"We're looking into that," Buck said. "We don't know right now. It's too early to say."

Other roads remained closed because of sinkholes. Trapnell Road has three sinkholes or depressions east of Turkey Creek. Sinkholes also have closed Branch Forbes Road as well as the I-4 eastbound exit ramp to Branch Forbes Road.

DOT officials say core drilling has begun and, as of Wednesday morning, about 250 cubic yards of grout had been poured in. Initial estimates call for about 400 cubic yards, officials say.