Beach-bound motorists could still be paying a toll to cross the Currituck Mid-county Bridge in 2072, the chief engineer with the span project suggested last week.

Right now, the North Carolina Turnpike Authority is projecting that motorists will pay as much as a $12 toll for a two-way trip across the planned seven-mile span for a period of 39 years. The toll will be collected to pay back investors who are expected to front the bulk of the money needed to fund the $459.6 million project.

Brett A. Clark/Daily Advance (ENLARGE)

Ben Baum of Aydlett points to one of the maps of the proposed Mid-Currituck Bridge during a citizens informational workshop at W.T. Griggs Elementary School in Poplar Branch Wednesday. The N.C. Turnpike Authority has suggested that the toll collected on the bridge may have to be extended from 39 years to as long as 59 years to pay of the project's investors.

If the bridge linking Currituck's mainland and Outer Banks opens as planned in 2013, the Turnpike Authority's current timetable has the toll being collected through 2052. But that plan may have to change if current traffic volumes don't rise.

Steve DeWitt, chief engineer with the Turnpike Authority, said last week that based on current traffic projections, a toll would generate only $260.7 million in revenue over 39 years. That's $198.9 million less than the current cost estimate for the project.

The likely source of additional funding to bridge the gap, DeWitt said, would be an extension of the toll.

"It could be ten more years. It could be twenty more years," he said, referring to how long the Turnpike Authority may have to extend the bridge toll. "It depends upon how much traffic grows. The more traffic grows, the more revenue you have. There are a lot of variables" involved.

One thing is certain. Little, if any, state funding will be available for the project.

"The transportation financing problems in the state are quite large," DeWitt said. "That is why the toll authority was created. This (bridge) is really being designed to be a user-fee (funded) project."

Increasing the toll could be an option, but that, too, may be unlikely. The Turnpike Authority conducted a study that evaluated projected traffic on the bridge over a typical 39-year bonding period. It also evaluated how much of a toll drivers would be willing to pay before they balked at using the bridge. The highest toll quoted by authority officials so far is $12 for a two-way trip.

The likeliest source for the additional $198.9 million needed to complete the project are private investors, DeWitt said. Investors are already expected to front the $260.7 million that will be paid back with toll revenues. But the private sector may be asked to play an even greater funding role.

In the next month, the Turnpike Authority plans to advertise the mid-county bridge to companies willing to invest in the project, DeWitt said.

"It is somewhat of a complex financing process, but they'd get their money back in the end," he said. "They'd have to recoup some costs during the process."

It's unclear whether the private company would manage the bridge or the state would simply turn over toll revenues as a return on a firm's investment in the project, DeWitt said.

"There are ten or 12 of these kinds of concepts used in the U.S.," he said. "It is not overly common, so there is still a lot of learning going on about the best way to negotiate these deals, and it is a negotiated deal."

After an environmental review of the bridge project is completed in August 2009, Turnpike Authority officials plan to put together a team to negotiate a deal with a private firm to build and operate the bridge.

"We'd expect that team to be comprised of a contractor, a designer and financier," DeWitt said. "We'll literally sit down across the table with them and negotiate the project."

The fact that the authority is proposing a two-lane bridge disappointed a number of Currituck residents who attended public workshops on the bridge project last week. DeWitt said a four-lane bridge would have added even more to the project's cost. He also said a 20-year traffic evaluation did not justify a four-lane span.

"There is a delicate balance here with the cost of project versus the revenue it can bring in," he said.

DeWitt said the bridge will be designed to have 10-foot shoulders so that drivers can pull over if they have car problems.