With Bonner Bridge open again for N.C. 12 traffic on the Outer Banks, a state Department of Transportation contractor expects in the next couple of days to begin building a protective structure of concrete and sandbags around bridge supports that had been undermined by the turbulent waters of Oregon Inlet.
The bridge that links Hatteras Island to the mainland reopened Sunday, 13 days after it was closed because of safety concerns. Pilings that had been standing in sand only 13 to 20 feet deep were shored up in a two-day dredging operation that dumped 30,000 cubic yards of sand around the supports.
Recent sonar scans and diver inspections confirmed that the pilings now are buried 30 to 35 feet deep, and tests showed that the bridge is stable and strong enough to support traffic safely, said Jerry Jennings, who oversees DOT operations in 14 northeastern counties.
After the bridge was reopened Sunday, DOT halted operations Monday morning for an emergency ferry service that had linked Hatteras Island to the Dare County mainland.
“Things are definitely looking better,” Jennings said Monday. “Our primary concern now is ensuring that all the sand that was placed there gets stabilized and remains in place. So we’re moving forward quickly with the project to get these materials on top of that sand so it does not begin to erode.”
DOT has repaired the 50-year-old bridge several times in the past, but this was the first time it had been closed because of severe and rapid scouring or erosion. Now that cars and trucks are moving across the bridge again, what follows will be more like a normal repair job.
Carolina Bridge Co. of Orangeburg, S.C., has a $1.6 million contract to make the emergency repairs. Over the past week, workers have been filling giant sandbags and assembling interlocking, concrete structures called A-Jacks.
In the next couple of days, Jennings said, a crane on a barge will begin lowering the A-Jacks and sandbags into place, building a big box around the weakened bridge supports to prevent further erosion.
The repairs may require occasional closings of the bridge, DOT said, but Dare County residents and travelers will receive advance notice.
The contract gives Carolina Bridge Co. 90 days to finish the work. Jennings said it was difficult to predict how long it will take. Much of the work can be done only during slack tides – at low and high tides, when the inlet current is less turbulent.
“And at this time of year, the weather is always a wild card,” Jennings said.
DOT awarded a $215.8 million contract in 2011 for a new structure to replace Bonner Bridge, but the work has been stalled by lawsuits in federal court and the state Office of Administrative Hearings.
Gov. Pat McCrory and DOT Secretary Tony Tata recently criticized the nonprofit Southern Environmental Law Center, which represents two environmental groups suing to block the bridge, and called on them to drop the case. SELC lawyers argue that DOT should have chosen to build a 17-mile bridge that would bypass the Pea Island National Wildlife Refuge, instead of the 2.8-mile Bonner replacement bridge.