It will likely be at least a week before transportation officials in the Carolinas know exactly how badly Florence has damaged roads and bridges. But based on past storms, the repairs will likely take months and cost tens of millions of dollars.
As of Friday, more than 840 roads in the Carolinas were still closed, including 169 in South Carolina and 656 in North Carolina. Among them are stretches of Interstate 40. Sections of Interstate 95 in Dillon and Florence counties opened in both directions Friday afternoon.
More road closures could occur as rivers crest in coming days. Rain water that bloated N.C. rivers is still making its way into South Carolina, prompting warnings of a second wave of flooding in the Pee Dee region and Horry County.
“We’re still waiting on the flood waters to finish rising and travel through the region,” said S.C. Transportation Secretary Christy Hall.
In North Carolina, Florence has the potential to be the most destructive storm in recent history to hit that state’s roads and bridges, according to the N.C. transportation chief. So far, at least 300 N.C. road and bridge sites need long-term repair, said N.C. Transportation Secretary James Trogdon Friday.
Across the Carolinas, torrents of water are testing already-fragile roads and bridges.
Some bridges with deteriorating supports span rivers that have experienced major flooding from Florence, The Charlotte Observer has found.
Transportation officials won’t be able to assess the damage on some roads until the water recedes.
“We may luck out and have minimal damage,” said N.C. DOT spokesman Steve Abbott. “Then again, there may be damage to hundreds of roads. You just don’t know until the water goes away.”
Financial help is likely on the way.
Thursday, S.C. Gov. Henry McMaster requested $1.2 billion in federal aid, including $18 million from the Federal Highway Administration. That total request is representative of South Carolina’s early estimate of losses, based on previous storms, S.C. Emergency Management Division director Kim Stenson stated in the governor’s request.
State dollars could follow. After previous S.C. storms, state money has typically been doled out through the Legislature’s annual budget process.
In North Carolina, the Federal Highway Administration has already announced $14 million in “quick release” emergency funds to help restore access to the state’s essential roads and bridges damaged by Florence.
South Carolina will get $8 million in “quick release” emergency funds, the S.C. Governor’s Office said.
Road damage can create a perilous situation for motorists.
In Chesterfield County, northeast of Columbia, a section of Old Wire Road caved in after Florence’s waters washed away the clay beneath. Marlboro County resident Crystal Simmons said a friend totaled his car Sunday night after driving into the hole in the rural two-lane road.
“Good thing he wasn’t going faster than 55 (mph),” Simmons said. “He wouldn’t be alive.”
What past storms teach us
After South Carolina’s historic flooding in October 2015, road and bridge repairs cost $137 million with the state paying about $49 million of that cost, S.C. DOT said at the time.
Some repairs took many months, forcing residents to take alternative routes. For example, one bridge near Columbia that washed out took eight months to rebuild.
And when Hurricane Matthew brought catastrophic flooding to eastern North Carolina in October 2016, hundreds of roads and bridges were damaged. It was more than a year before they were were all fully repaired.
The total repair cost: Almost $200 million. The federal government covered about three quarters of that amount and the state covered the rest.
Some old bridges at risk
More than 400 bridges cross North and South Carolina rivers that reached “major” flood levels as a result of the storm, according to an Observer analysis of data from the U.S. Department of Transportation and the National Weather Service.
Those include the the Waccamaw and Pee Dee rivers in South Carolina and Cape Fear, Neuse and Lumber rivers in North Carolina.
Collectively, these bridges carry more than 2.9 million drivers daily, data show.
Brian Hanks, state structures engineer for N.C. DOT, said floods can damage bridges, especially if the structures are already in poor condition.
Rushing water can send debris smashing into pilings or cause bridge decks to separate from their supports.
If water has washed away sediment from beneath bridge piers, or if those piers have deteriorated, bridges can become more vulnerable, Hanks said.
Often, such bridges are old and were not built to current standards, he said.
About 40 bridges along the majorly flooded rivers in the Carolinas have deteriorated piers or sediment that has washed away, data show. Half are at least 60 years old.
Barry Moose, senior vice present at SEPI Engineering, spent more than 27 years with N.C. DOT. But he never saw some rivers rise as high as they did last week, he said.
“The water is moving very fast,” Moose said. “It can move a lot of material (from underneath a bridge) in a very short amount of time.”
Hanks said more than 20 teams of bridge inspectors are working along the coast.
N.C. officials have already inspected more than 1,100 bridges, closing nearly 100 of them, Abbott said. More than 75 bridges in South Carolina were closed as of Friday.
Preparing and repairing
Transportation officials took steps to prepare roads for flooding.
For example, S.C. DOT staff built flood barriers at the U.S. 501 Bypass in Conway and on the U.S. 378 crossing over Lynches River in Florence County.
Transportation officials used data on rainfall and road elevations to anticipate trouble spots as water traveled down from North Carolina, said Andy Leaphart, chief engineer for operations for the S.C. transportation department.
“To keep roads passable and keep a lifeline in and out of the coastal areas, we’re trying to make sure … that we shore up areas,” Leaphart said Wednesday.
Once flood waters recede, transportation officials will inspect roads and bridges for damage. Those deemed unsafe will be closed, officials say.
Road washouts and culvert failures have been the most common types of damage that S.C. officials have seen from Florence so far, Leaphart said.
The S.C. state transportation agency will bring in contractors, using the private sector to help speed up repairs, said secretary Hall.
Interstates are generally the first priority for repairs, she said. Then, S.C. DOT will fix the state’s most-traveled roads, called primary roads, as well as roads to critical facilities such as schools and hospitals.
“If we can make an immediate, emergency-type repair to get the road or bridge reopened, then we’ll do that,” Hall said.
If a road passes inspection, then the state will reopen it, she said.
But if inspectors spot problems, then they do a more detailed inspection, Leaphart said.
How long repairs will take depends on the extent of damage, said Andrew Herrmann, a past president of American Society of Civil Engineers.
“Rebuilding really depends on manpower and dollars,” he said.
How do motorists know if a road is unsafe? Look for the barricades, transportation officials say.
“We’re going to reopen roads as soon as they’re safe for travel,” said Tim Anderson of the N.C. DOT. “If we have a barricade, it’s there for the safety of the traveling public.”