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Pearman, Grace bridge demolition methods change
By Dan McCue
Staff Writer
In a marked change of demolition strategy, the center spans of the Pearman and Grace bridges will be lowered onto barges and removed to a nearby recycling facility on Feb. 22 and March 1, respectively, rather than blown up as other sections of the bridges have been.
The South Carolina Department of Transportation, the U.S. Coast Guard and the region’s public and private port operators have all endorsed the revised demolition plan, which calls for a complete closure of the shipping channel for eight to 24 hours on the days the spans are being lowered.
Among the facilities that will be directly affected by that closure are the South Carolina State Ports Authority’s Wando Welch, Veterans and North Charleston terminals. Also impacted will be the privately owned bulk product and oil terminals, all of which are upriver from the projects.
Service to the Union Pier and Columbus Street terminals will be unaffected.
“All in all, this is only a minimal disruption of shipping traffic in a navigation channel that’s the life blood of the Port of Charleston, and frankly, we’re very pleased with the plan,” SPA spokesman Byron Miller said.
“We all recognize that for us to realize the benefits of the new bridge, the old bridges have to come down. Given the concerns we all had regarding potential longer term disruptions associated with the explosion/recovery method of demolition that was used earlier in the project, we see this new approach as creating only a short term issue for our long term benefit.”
Leland Colvin, demolition project director for the SCDOT, said Mammoet, a Netherlands-based specialist in offshore heavy lifting and transport projects, will perform the work, which involves the use of specialized cranes and an elaborate jack and cable system.
He stressed that the change in procedures will add no additional costs to the project, which has a projected price tag of $57.5 million.
Asked about the change in demolition methods during a press conference at the U.S. Coast Guard Pier in downtown Charleston, Colvin said the demolition of the Pearman and Grace bridges has been an evolving process from the beginning.
“The change in procedure basically stems from the contractor determining this would be a safer, more effective way to proceed with the removal of these sections,” he explained. “Certainly, anytime you can prevent the intrusion of a piece of a demolition project into the water, the better.”
But he added, “It’s yet to be determined whether the back spars of the bridges will be blown up or removed by this other method.”
According to Capt. John E. Cameron, the Coast Guard’s sector commander and captain of the port, the navigational channel of the Cooper River will be narrowed from 600 to 380 feet for about six days before the removal of the bridge sections takes place.
“This will help facilitate Mammoet towing its equipment into place, installing four jack stands and cable stations into place for each bridge, and anchoring the receiving barges into position,” Cameron said, adding that even narrowed to this extent, the navigation channel will still be roughly twice the width of a seagoing cargo ship.
Weather permitting, meaning winds below 25 knots and no lightening present, the removal of the 380-foot, 535-ton section of the Pearman Bridge will begin around dawn on Wednesday, Feb. 22. Cameron said lowering the section 150 feet to the barge should take six to eight hours.
If for some reason the work can’t be done on that day, Cameron said a second attempt would be made on Thursday, Feb. 23.
The following week, on Wednesday, March 1, a 430-foot, 440-ton section of the Grace bridge will be lowered the same way. As in the case of the Pearman, in the event of a weather-related delay, the lowering would be done a day later, on Thursday, March 1.
If weather scrubs either one of the removals completely, it will be rescheduled for March 8, Cameron said.
“In scheduling this work, we made every effort to be sensitive to the needs of the port community,” Cameron said. “The affected parties told us that the middle of the week was their slowest time, so we devised our schedule accordingly.”
Cameron said traffic on the Arthur Ravanel Jr. Bridge will be unaffected during the demolition process.
Dan McCue is a staff writer for the Business Journal. E-mail him at dmccue@charlestonbusiness.com.
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