Elizabeth Mabry, executive director of the South Carolina Department of Transportation, and other transportation officials said the amount of cracking on the bridges has caught them by surprise. If the cracking doesn't stop, the bridges will need more long-term maintenance than usual, the officials acknowledged.
But they said they won't know for at least another six months whether the cracking will continue and how serious a problem it might turn out to be.
"I know that some cracking is normal," Mabry said. "But the question to me too is how much cracking is normal, and is this normal? ... That's what we're trying to determine."
Soon after the cracks began appearing in November 2003, the department hired an independent consulting firm to "look at this structure and tell us what they see," Mabry said.
The firm will continue to analyze the cracking during the coming months, department officials said. But until February, when the bridges will have been open for a full year -- exposed to the seasonal changes in temperature and a steady flow of traffic -- the state won't have the full picture, they said.
"I don't know what the answer is yet on the cracks -- I'll just tell you that right now," Mabry said.
IMPORTANT LINK
The bridges are part of the $105 million widening of S.C. 170, the highway linking northern and southern Beaufort County. The department hired Balfour Beatty, a firm based in England, to design and build the massive project after the company submitted a bid that was $23 million lower than the nearest competitor. Beaufort County residents contributed about $30 million to the project through a temporary 1 percent sales tax.
Cracks began appearing on the bridges' decks almost immediately after the concrete decking hardened last fall, and work crews have been busy patching them with an epoxy sealant -- first on one side of the Broad River bridge and then on the other -- almost continually since the Jan. 20 opening.
The cracking on the bridges appears to be far more excessive than on other recently built bridges, according to several private-sector engineers interviewed by The Island Packet.
Mabry and her top engineers, speaking at a meeting at the department's headquarters, said department officials began noticing the cracks after work crews began clearing debris from the Broad River Bridge and grinding its deck to give it the desired texture.
Concerned about the number of cracks they saw, they hired an engineering consulting firm, Ralph Whitehead Associates of Charlotte, to take a closer look. Firm officials said Friday that they believe the bridges are structurally sound at this point. One explanation for the cracking is that the bridges' design differs from others around the state, they said.
Statements made by officials at Friday's meeting about the severity of the problem contrasted with ones made at a public meeting June 24, when Charles Eleazer, an assistant construction engineer, said the Broad River bridge had "a few more cracks than you would normally see." In an Aug. 3 meeting, department officials said the amount of cracking was higher than normal but not unusual.
Aubrey Swofford, a retired engineer from Okatie who dealt extensively with concrete during his career, noticed the cracking on the two bridges and compared it with other bridges built recently along the state's coast.
The Paul J. Gelegotis Memorial Bridge in Charleston County has about 572 feet of cracks per mile, the most of any of the other bridges Swofford examined. The Broad River bridge has more than 14,000 feet of cracks per mile, according to Swofford's calculations.
The extensive sealing operation that has been going on for the past several months is aimed at closing the cracks to prevent moisture from getting in. Cracks can provide a route for moisture to seep into the bridges' interiors and corrode steel reinforcing rods embedded in the concrete.
Some of the cracks -- measured in thousandths of inches but still wide enough to allow moisture in -- go all the way through the bridge, officials said. If the steel rods are corroded, the bridges would be weakened, although DOT officials said they've seen no evidence of corrosion.
Mabry said the state has received a number of inquiries from residents concerned about the cracking. The Island Packet also has received such inquires.
"We're concerned also," Mabry said, "because we want to make sure this is a quality project."
CAUSE UNKNOWN
Transportation engineers said they haven't determined the cause of the cracking. Rocque Kneece, the department's program development director, said the year-long analysis expected to conclude in February is aimed at:
The officials said they hope the long-delayed S.C. 170 project would be finished by November. That will be more than a year after the original finishing date of Oct. 24, 2003.
But officials also said Balfour Beatty, not taxpayers, probably will be responsible for paying repair costs in the near future. The company would be required to pay for maintenance of the bridges over the next decade if the state accepts the work and the current contract is finalized.
Mabry, the transportation department's executive director, said she thought the Broad River bridge was safe but was concerned about its appearance. She mentioned several times Friday that her department is considering adding an "overlay" to the bridge, which would be an additional layer of concrete, acrylic or other material intended to improve the look.
Tony Chapman, a deputy state highway engineer, said the costs for an overlay vary and did not give an estimate, other than to say "they're costly."
But that's a discussion at least six months down the road, Mabry said. In the meantime, the state needs to determine the cause or causes of the cracking.
Kneece, the program development director, said he thought most of the cracking would stop by February 2005, the one-year mark. If it does, the 100-year lifespan of the bridges should not be reduced.
When asked if the state had considered firing Balfour Beatty, Mabry said she had. But she added that the process of doing so was complicated and that finding another contractor to finish the work would cost considerable time, effort and money.
The state temporarily has withheld about $5 million of the contract for a couple of reasons, said Chapman, the highway engineer.
About $3 million of the money comes from potential late fines against Balfour Beatty, which are intended to provide an incentive to finish in a timely manner. About one-third of the fines would go to Beaufort County, which paid for about one-third of the S.C. 170 project through the 1 percent sales tax approved in 1998.
The remaining $2 million is being withheld to ensure the state can finish the project if Balfour Beatty cannot, Chapman said. The final amount to be withheld from Balfour Beatty will not be determined until the two sides negotiate the final details of the contract.
"We're not going to let the contractor get off with a project that's inadequate," he added. "We think the company will finish the work. It's really a matter of when."