Florence could be the most destructive storm in recent history to hit North Carolina’s roads and bridges, according to the state’s transportation chief.
So far, at least 300 N.C. road and bridge sites need long-term repair, state Transportation Secretary James Trogdon told the Observer Friday. And officials may find much more damage when the floodwaters recede.
“That number could easily double in the next week,” Trogdon said. “It’s a large number with the potential to get larger.”
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, one thing is clear: The repairs can be expected to take months and cost tens of millions of dollars.
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Damage from the storm stretched from the coast to as far west as Ashe County, north of Hickory, Trogdon said.
“I would tell you the damages are pretty widespread across North Carolina, and that’s the first time I’ve ever seen this many counties impacted by something other than a snowstorm,” Trogdon said.
As of Friday, more than 840 roads in the Carolinas were still closed, including about 656 in North Carolina and about 189 in South Carolina. Among them are stretches of Interstate 40 and Interstate 95.
And more road closures could occur as some rivers crest this weekend. “We’re still waiting on the floodwaters to finish rising and travel through the region,” S.C. Transportation Secretary Christy Hall told the Observer.
In some places, torrents of water have tested already fragile roads and bridges.
Some bridges with deteriorating supports span rivers that experienced major flooding, the Observer 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. Department of Transportation spokesman Steve Abbott. “Then again, there may be damage to hundreds of roads. You just don’t know until the water goes away.”
In repairing roads, NCDOT focuses first on the interstates, then on the U.S. routes and then on the state routes and local roads. Repairs are often delayed by the weather. Some work — such as asphalt paving — can’t be done during the cold-weather months of winter.
“It’s possible they won’t be able to get to some places until next spring,” Abbott said.
Federal help is already on the way.
On Thursday, the Federal Highway Administration announced it would make $14 million in “quick release” emergency funds available to North Carolina to help restore access to essential roads and bridges damaged by Florence.
Trogdon said that transportation officials estimate the N.C. damage at $75-$80 million so far. That number could double, he said.
The road damage can create a perilous situation for motorists.
In Chesterfield County, S.C., northeast of Columbia, a section of Old Wire Road caved in after Florence’s waters washed away the clay beneath. Chesterfield 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
When Hurricane Matthew brought catastrophic flooding to eastern North Carolina in October 2016, hundreds of roads and bridges were damaged. And it was more than a year before they were 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.
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, SCDOT said at the time.
Some repairs took many months, forcing residents to take alternative routes. For example, one S.C. bridge near Columbia that washed out took eight months to rebuild.
Some old bridges at risk
More than 400 bridges cross North and South Carolina rivers reached “major” flood levels, according to an Observer analysis of data from the U.S. Department of Transportation and the National Weather Service.
Those include the Cape Fear, Neuse and Lumber rivers in North Carolina and the Waccamaw and Pee-Dee rivers in South Carolina.
Together, these bridges carry more than 2.9 million drivers a day, data show.
Brian Hanks, state structures engineer for NCDOT, 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 to floods, 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 NCDOT. 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.
In the division that covers Mecklenburg and the four counties to the east, 11 bridges were closed as of Thursday.
How storms damage roads
Asphalt paving is designed to weather the elements. But when major storms hit, currents of water can wash away the gravel and dirt that support roads.
That’s what happened to many roads in counties east of Charlotte.
As of Thursday, Union, Anson, Stanly and Cabarrus counties had 57 roads closed due to storm damage, according to Tim Anderson, the top maintenance engineer for that DOT division.
Anderson said DOT officials are still inspecting the damage to roads and bridges, and should be finished with their assessment by the end of next week. Officials don’t yet know how long all the repairs will take, but Anderson estimates it will take months to complete.
Preparing and repairing
Transportation officials took steps to prepare roads for flooding.
For example, SCDOT 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.
They used data on rainfall and road elevations to anticipate trouble spots as waters 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 floodwaters 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 SCDOT will bring in contractors, using the private sector to help speed up repairs, said Secretary Hall.
“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 the 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 Anderson, the Charlotte-area maintenance engineer. “If we have a barricade, it’s there for the safety of the traveling public.”
The State reporter Maayan Schechter contributed.