|Dredging Scheduled to Begin Tomorrow at Bonner Bridge
||Thursday, December 05, 2013
RALEIGH — Plans are currently underway for dredging to begin at the Herbert C. Bonner Bridge on N.C. 12 over the Oregon Inlet in Dare County. The N.C. Department of Transportation and Great Lakes Dredge and Dock Co. LLC have come to an agreement for the Dredge Alaska to begin dredging sand from the main navigation channel of the Oregon Inlet and deposit it on the area underneath the Bonner Bridge where scour caused the department to close the bridge earlier this week.
Crews this morning began preparing for the dredging operation, which is currently expected to begin Friday afternoon at the earliest and last two days, weather and current permitting.
Once dredging operations are complete, NCDOT crews will then perform additional scans and inspections of the piles to determine the next steps necessary in reopening the bridge.
Earlier today, North Carolina Governor Pat McCrory declared a State of Emergency due to the closing of the Bonner Bridge.
“This declaration will give us the flexibility we need to get the repairs done as quickly as possible,” said Governor Pat McCrory. “However, safety will be the sole factor in determining when the Bonner Bridge reopens to traffic.”
NCDOT earlier this week awarded a $1.6 million contract to Carolina Bridge Company Inc. of Orangeburg, S.C. for emergency repairs on the bridge. NCDOT and the contractor are working together to develop a timeframe for the repairs to be complete.
As part of this emergency repair project, crews will use sandbags and four-foot tall A-Jacks to provide support to the bridge pilings. A-Jacks locked together will be placed in a perimeter around the support structure of the bridge. Crews will then fill the perimeter with sandbags to provide support to the pilings. 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 protection. This will allow sand to collect over the sandbags and A-Jacks, providing additional support to the structure.
Emergency Ferry Route
NCDOT’s Ferry Division activated its emergency route between Stumpy Point and Rodanthe with limited service on Tuesday after the bridge closure. The route went into full operation Wednesday, 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. Ferry information is available on the Ferry Division website, by calling 800-293-3779, or via Facebook (North Carolina Ferry System) and Twitter @NCDOT_Ferry).
NCDOT closed the Bonner Bridge the afternoon of Tuesday, Dec. 3. Routine sonar scanning of the bridge had identified scouring concerns, or areas where too much sand has eroded from the support structure of the bridge. As NCDOT crews continued to monitor these conditions, inspections revealed that scour was occurring more rapidly than it had been previously, which led department officials to decide to close the bridge immediately for the safety of all residents and visitors of the area.
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.
(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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Photo of the Dredge Alaska, courtesy of Great Lakes Dredge and Dock Co. LLC