Will sea-level rise make this $500 million bridge to the Outer Banks obsolete or essential?

The Mid-Currituck Bridge would cross Currituck Sound from the mainland to Corolla, an area of the Outer Banks known for wild horses.
The Mid-Currituck Bridge would cross Currituck Sound from the mainland to Corolla, an area of the Outer Banks known for wild horses. AP

The state wants to build a 4.7-mile toll bridge across Currituck Sound to make it easier for residents and tourists to get on and off the northern Outer Banks, particularly in advance of a hurricane.

But opponents of the Mid-Currituck Bridge say it would unnecessarily harm natural areas in and around the sound and that state and federal transportation agencies have failed to fully assess its viability, particularly in the face of rising sea level.

They say recent estimates of sea-level rise show the approaches to the bridge would be vulnerable to flooding by 2050 and that inundation of low-lying areas would reduce development, cutting into the toll revenue that’s expected to help pay for the $500 million project in coming decades.

The N.C. Wildlife Federation and a citizens’ group called No Mid-Currituck Bridge make those arguments in a lawsuit filed Tuesday in federal court. The suit asks the court to block construction of the bridge and order the N.C. Department of Transportation and the Federal Highway Administration to do another study of the need for the project and its environmental impacts.

“It is unfortunate that Governor Cooper’s NCDOT continues to press forward with this wasteful, destructive bridge” Kym Hunter, an attorney for the Southern Environmental Law Center, which filed the lawsuit, said in a statement. “It’s hard to square the governor’s executive order on climate change with this bridge that will encourage more development in a part of North Carolina vulnerable to rising sea levels and coastal flooding.”

Mid-Currituck Bridge map.jpg
The Mid-Currituck Bridge would extend 4.7 miles across Currituck Sound to Corolla and would include a separate 1.5-mile bridge over Maple Swamp. NCDOT

Years of planning

The Mid-Currituck Bridge would connect U.S. 158 near Aydlett with N.C. 12 in Corolla, providing an alternative to the Wright Memorial Bridge at Kitty Hawk. For drivers coming south from Virginia, the new two-lane toll bridge would provide a 40-mile shortcut to Corolla, saving up to two hours of drive time each way during busy summer weekends, according to NCDOT.

Planning for the bridge began in the mid 1990s, but support has waxed and waned over the years. In 2009, state officials expected that an international group of private companies would work with the N.C. Turnpike Authority to finance and build the bridge, but legislators balked at giving it special status and decided in 2012 that it should compete with other road projects for state funding.

That same year, NCDOT, the Turnpike Authority and the Federal Highway Administration approved an environmental impact report that spelled out the need for the project and its effects on the environment. It’s that document that opponents say failed to adequately consider less destructive alternatives and is now out of date because of new predictions about sea-level rise.

Specifically, according to the lawsuit, the transportation agencies cited the state Coastal Resources Commission, whose science panel in 2010 predicted a 39-inch rise in sea level along the Outer Banks by 2100. According to the lawsuit, more recent forecasts from the National Oceanic and Atmospheric Administration put the likely rise at about 81 inches in that time.

“The science behind sea-level rise, storm surge and climate change models has significantly advanced — with implications for the durability of the toll bridge, its utility as a hurricane evacuation route, and its financial viability as a toll revenue generating facility,” the lawsuit says.

In approving the Mid-Currituck Bridge early last month, the Federal Highway Administration concluded that “no component” of the project would be affected by sea-level rise and that the bridge “could be a useful asset in reducing the impact of sea-level rise on the project area’s road system.” It noted that eventually the Outer Banks will likely be inundated at the Dare/Currituck county line, south of Corolla, “creating a breach in the island and making a Mid-Currituck Bridge the only way off the Currituck County Outer Banks.”

The federal agency also concluded that “no new significant issues or impacts” had come up since 2012 to invalidate the environmental impact report.

In addition to the main bridge over the sound, the project also includes a 1.5-mile bridge over Maple Swamp on the mainland side. The toll plaza would be near the intersection with U.S. 158. The toll rates would not be set until the bridge is close to opening, and construction is not scheduled to begin until 2021, said Carly Olexik, spokeswoman for the turnpike authority.

The authority and NCDOT don’t comment on lawsuits, Olexik said.

Alternatives to the bridge

Opponents say there would be much cheaper and less destructive ways to relieve summer weekend traffic, including widening key stretches of N.C. 12, redesigning the intersection of N.C. 12 and U.S. 158 in Kitty Hawk and staggering check-out days at vacation rentals.

“The proposed bridge would only really be used for 13 weekends a year during peak vacation time,” Jen Symonds, a founder of No Mid-Currituck Bridge, said in a statement. “$500 million is just too much to spend on vacation traffic when there are so many other needed transportation projects in coastal North Carolina, and so many alternative solutions to deal with the traffic.”

The Southern Environmental Law Center has sought to stop or modify several high-profile road projects in North Carolina. The organization has taken steps on behalf of environmental groups to block construction of the Triangle Expressway, a planned six-lane toll road across southern Wake County, claiming it would unnecessarily spur sprawling development and harm three species of rare freshwater mussels.

While its relationship with NCDOT is often adversarial, not all of the disputes between the state and the law center end up that way. Last year, the center and two environmental groups agreed to drop their opposition to construction of a U.S. 70 bypass around Havelock, near Marine Corps Air Station Cherry Point, in exchange for several steps by NCDOT to protect rare longleaf pine habitat along the highway’s path.

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Richard Stradling covers transportation for The News & Observer. Planes, trains and automobiles, plus ferries, bicycles, scooters and just plain walking. Also, #census2020. He’s been a reporter or editor for 32 years, including the last 20 at The N&O. 919-829-4739, rstradling@newsobserver.com.