SPRING HILL — The bad news is that the contractor working on Mariner Boulevard to permanently repair sinkholes that formed during Tropical Storm Debby opened up another 6-foot-wide, 8-foot-deep hole this week.
The good news: The additional hole is not expected to lengthen the time the roadway will be closed to through traffic.
As originally announced, the stretch of the road just north of Spring Hill Drive should reopen by 6 p.m. Dec. 14, Brian Malmberg, the county’s director of transportation services, said Wednesday.
Delays caused by the detours along Linden Drive and Maderia Street have lit up the switchboard at the county’s transportation services office since the road closure began at 7 a.m. Monday.
In late June, Debby dumped more than a foot of rain across Hernando County, and sinkholes appeared on Mariner Boulevard, surrounding streets and at numerous other locations. For 10 days, the stretch of busy roadway, which sees about 21,000 vehicles a day, was closed as temporary repairs were made using fill dirt.
Workers then patched the road, and traffic resumed. At the time, officials said they believed the underground weaknesses were isolated.
As equipment arrived at the site several days ago and permanent repairs began, the new hole appeared. Like the other voids, the new hole will be filled with concrete grout and pins, the same process used for homes found to have sinkholes, officials said.
The county hired LRE Ground Services for the job after seeking quotes. The job will cost $181,155, considerably less than the original estimate of $350,000.
“You just don’t know how much grout you’re going to pump,” Malmberg said.
Filling the new hole with grout will probably cost another $8,000, according to Mark Guttman, engineering services manager for the county.
Guttman said the holes on Mariner were not immediately repaired with grout because the county didn’t have the money. But once officials learned that they could seek reimbursement for the repairs through the Federal Highway Administration, they moved forward with the permanent fix, seeking quotes for the work under emergency rules.
The County Commission will be asked to ratify the contract later this month.
After the grout work is completed next week, the county will allow the ground to settle for two weeks. If there is no need for further repairs, final paving will begin.
Malmberg noted that the paving will be done one lane at a time, so he does not anticipate having to close the entire stretch of Mariner during that process.