Though its reopening Saturday would bring a welcome early end to a two-week traffic nightmare, a Wando River bridge will need constant care and more repairs to prevent another shutdown of the critical link in the Charleston region.
A broken support cable has been replaced with two new ones, officials announced Thursday, more than a week ahead of a June 11 target completion date. Corrosion likely caused the rupture that was found May 14, prompting the emergency closure of the James B. Edwards Bridge over westbound Interstate 526, they said.
State Department of Transportation Secretary Christy Hall said the temporary repairs had gone well, but more fixes are needed to seal the span from rainwater intrusion that was identified at least eight years ago as a leading cause of the rust eating away at the crucial support cables.
“We understand the importance of these bridges,” Hall said Thursday during a briefing. “We will take whatever steps necessary in order to ensure our citizens are riding on safe bridges.”
Federal authorities and experts from private engineering firms and from Florida, where similarly designed bridges are more common, concurred with the Saturday reopening of the span "weather permitting," Hall said.
The closure had snarled traffic in East Cooper for a week until the state allowed two-way traffic over the unaffected eastbound lanes of the bridge, shifting the gridlock to North Charleston.
Few who use the region’s roads have been untouched. Commutes between North Charleston and Mount Pleasant have been a chore. Trucks heading from a busy port near Mount Pleasant also saw delays. Some motorists have sat in traffic for more than two hours.
Crews had been examining the bridge weekly since a corroded cable needed repairs in 2016. One of those reviews found a ruptured line near the center of the bridge, not far from the discovery two years ago.
Water had been leaking into areas above the bridge’s concrete pillars that are driven deep into the riverbed. Workers refilled five of those area with concrete and resealed the rest of the 51 problem spots.
Further efforts to cap other areas from water flow will be done while the bridge is open, officials said.
While the bridge was built with eight primary cables that hold together its many concrete segments, the westbound span now has nine after two new ones were added — a "redundancy" plan in case more problems emerge.
“With some maintenance performed on these bridges, we will be able to have safe structures … that can serve the area for decades to to come,” Hall said.
That will take daily inspections of the twin spans until the state installs acoustical monitors to help evaluate the reliability of concrete-encased cables that experts cannot reach, DOT Deputy Secretary of Engineering Leland Colvin said. The agency sought federal funding in 2002 and again in 2005 for the same equipment but never got it.
The other option for taking a peek at the cables is drilling through the top of the bridge, which would make “Swiss cheese” of the span, Colvin said.
But Colvin indicated a degree of uncertainty in the current monitoring endeavor. Experts had tested 16 miles of cable over the years, looking for corrosion that caused the recent mishap.
One of the sections they examined was within 2 feet of the break. They found no problems.