Doug and Bruce Stephens unsuccessfully lobbied state officials for years to build a road across their land between Interstate 84 and Washington Terrace.

Finally, they decided to build their own $8 million, half-mile-long road and put a toll on it as a business venture.

Five years later, 1,400 vehicles travel the road each weekday, with motorists paying 50 cents per axle for a one-way trip.

Meanwhile, legislation is planned in this year's general session that would allow public-private partnerships to build toll roads in Utah.

"We were kind of a guinea pig to see if people would accept the road, and it has been accepted well enough for us to pay off our bills, so we're kind of an example that future roads could succeed," said Breon Jacobs, manager of the Adams Avenue Parkway.

State Sen. Sheldon Killpack, R-Syracuse, who is sponsoring the bill that would allow public-private partnerships, notes there's a big difference between the Adams Avenue Parkway and what he is proposing.

For one, the public-private partnership projects would be much larger in scope, possibly beginning with the $2 billion, 35-mile Mountain View Corridor between the Salt Lake International Airport and Pleasant Grove.

And while the Adams Avenue Parkway is privately owned and operated, the state would retain ownership of the public-private toll roads.

But there is also a similarity.

Like the Adams Avenue Parkway, the partnerships would involve private investors funding roads the state can't afford.

Killpack said Utah is facing a $16.5 billion shortfall in road funding through 2030.

"In essence, this is a question of when do you want a road?" Killpack said, adding that transportation is critical for economic development. "You can build it now or you can wait another 20-plus years."

Under the bill, which has yet to be filed, the state would enter long-term contracts with concessionaires, Killpack said. The state would perform feasibility studies, but concessionaires would fund construction, operations, maintenance and traffic enforcement. They would collect toll revenue as a return on their investment.

Similar public-private partnership arrangements already are in place in 23 other states.

But the proposal to build the Mountain View Corridor as a toll road has riled some in western Salt Lake County, especially on the heels of the state's decision to fund Legacy Parkway through Davis County.

Killpack said there is no guarantee that Mountain View would be built as a toll road, and even if it were, there likely would be others to follow, including possibly the extension of Legacy from Farmington to Brigham City.

"My hunch is if we can have a road in a couple of years based on a toll road there may be some interest," he said. "I think that's an option."

Tom Hudachko, a spokesman for the Utah Department of Transportation, said the northern extension of Legacy currently is 10 years out, at best, in state plans and the project has no estimated price tag.

Aside from Mountain View, the northern corridor in St. George and U.S. Highway 6 in Central Utah were the only roads identified for possible tolls in a recent managed-lane study performed by UDOT, Hudachko said.

But like Killpack, he said, UDOT is supportive of the idea of public-private partnerships.

"We think it would provide the state just one more additional tool," he said. "It's very clear to see that there is nowhere near enough revenue."