RALEIGH —N.C. Department of Transportation engineers today are analyzing the data gathered yesterday from underwater surveys and the first of two pile tests to evaluate the overall effectiveness of the sand placed in the area where erosion occurred at the Bonner Bridge. Carolina Bridge Company Inc. is conducting a second pile test today that also will be used in the evaluation. Once engineers are able to analyze all the data and fully assess the bridge’s safety, the department will determine the best path forward for reopening the bridge.
According to NCDOT Division 1 Engineer Jerry Jennings, the timeframe for reopening the bridge could be within about a week or up to 90 days, depending on the findings of the assessment and timeline for repairs.
Approximately 30,000 cubic yards of sand were pumped during the weekend from the main navigation channel of the Oregon Inlet to the location at Bent 166 underneath the Bonner Bridge where scour, or the erosion of sand from bridge pilings, caused NCDOT to close the bridge on Tuesday, Dec. 3. Photos of the various activities conducted at the bridge can be found on NCDOT’s Flickr site.
NCDOT awarded a $1.6 million contract to Carolina Bridge Company Inc. of Orangeburg, S.C. last week for emergency repairs on the Bonner Bridge.
Crews will use sandbags and four-foot tall A-Jacks to provide support to the bridge pilings and prevent further scour from occurring. A-Jacks interlocked together will be placed around the perimeter of the support structure at Bent 166. Crews will then place sandbags inside the line of A-Jacks. An additional two layers of A-Jacks and sandbags will then be placed on top of the base layer for a total of 10-12 feet of additional protection. This will allow sand to collect over the sandbags and A-Jacks, providing additional support to the structure.
Contractor crews are filling sandbags, and mobilizing equipment and materials to the bridge site.
Emergency Ferry Route
NCDOT’s Ferry Division activated its emergency route between Stumpy Point and Rodanthe with limited service the night of the bridge closure. The route went into full operation Wednesday, Dec. 4, with steady traffic and short-to-moderate wait times reported at both terminals. Dare County Emergency Management has issued a priority loading list for the route. The emergency ferry route will continue seven days a week as long as service is needed. Ferry information is available on the Ferry Division website, by calling 800-293-3779, or via Facebook and Twitter at @NCDOT_Ferry.
For More Information
NCDOT will continue to update the public on this situation online and via its N.C. 12 Facebook page and N.C. 12 Twitter account.
While NCDOT is working hard to reopen the Bonner Bridge to traffic as quickly as possible, the emergency repairs are not considered a permanent fix for the aging bridge. After 50 years of weathering many storms, the bridge needs to be replaced. In July 2011, NCDOT awarded a $215.8 million contract for the design and construction of a new bridge. Design work began immediately and construction of the new bridge was set to begin in early 2013; however, lawsuits have put the project on hold.
Read more about the history of the Bonner Bridge and the challenges to replacing this lifeline.
(Editor’s note: Images of A-jacks are available at: http://www.flickr.com/photos/ncdot/6377484269/. These photos are from a scour prevention project at another span in 2011.)
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