Before the Suncoast Parkway opened, a consultant predicted that it would be so full of cars its toll booths would rake in $150 million a year by 2014.

That forecast wasn't close. Nor were the next two. The consultant eventually settled on a forecast of $38 million a year.

But when 2014 rolled around, the road was so empty it collected a mere $22 million.

Yet the Florida Department of Transportation now wants to spend $256.7 million to extend the Suncoast another 13 miles north through Citrus County. And the projections the DOT is relying on to justify what has been dubbed Suncoast 2 are from the same consultant that got the first phase so wrong.

"They're building this highway for cars that don't exist yet," said Ralf Brooks, an attorney who's trying to get the route moved so it won't obliterate a historic site in the Withlachoochee State Forest. "Is this just a way to make money for the companies that build roads and donate to candidates? Or are they trying to bring traffic to the developers?"

That same DOT consultant, San Francisco-based URS Greiner Woodward, provided overly sunny financial projections for the Veterans Expressway in Tampa; the Seminole Parkway near Sanford; the Polk Parkway near Lakeland; and the Garcon Point Bridge near Pensacola. In a 2000 interview with the Times, URS officials said they were "basically guessing."

According to Christa Deason of the agency's Turnpike Enterprise division, the changing numbers don't signify anything underhanded or incompetent. Traffic figures always change based on conditions beyond control, she said.

"Our guys are very good at forecasting, because they have to be," Deason said. "We have a history of success."

• • •

The firm's repeated miscalculations are troubling for Ken Wright, a land use attorney who serves on the Florida Transportation Committee, which oversees the DOT. He promised to bring it up at the commission's next meeting later this month.

"I know for a fact how significant those traffic projections are," Wright said. "A point comes where there's some reality that has to come into play."

But the Suncoast was always built on a foundation of dreams. When the $507 million toll road from northern Hillsborough to Hernando County first opened, its supporters were sure it would spark a massive building boom. New homes and stores would pop up all over. They would fill the 42-mile toll road with cars and trucks and the state's coffers with money.

Their desire for development fueled the wildly overblown projections by URS, which two years ago was taken over by a rival, Aecom, which now holds the $5.9 million annual contract for making toll road projections.

Toll roads aren't supposed to work this way. They are a way to build a highway without using taxpayer money. They are supposed to pay for themselves.

The road's owner borrows money to build the road, then charges drivers enough to cover the cost. That makes the toll projections before a road is built crucial in determining whether projects are viable. If the projections fall short, the road can't pay off its loans and its owner may go bankrupt.

Ignoring Florida's history of real estate boom-and-bust cycles, URS in its Suncoast 1 projections didn't account for a housing slowdown, which eventually came with the housing crash and the 2008 Great Recession.

As a result, the development boom that the road was intended to spark never caught fire. Land along the parkway is so empty of development that a SuperTarget store that opened to take advantage of the expected population boom closed in January.

"There's not much going on," said Dennis Dix, executive director of the Hernando/Citrus Metropolitan Planning Organization, which sets local road-building priorities.

Despite those declining prospects, the DOT is forging ahead with Suncoast 2 — although Dix said it would likely not attract as many drivers as Suncoast 1, given how far away it sits from Tampa Bay region's urban center.

• • •

The Suncoast 2 has been in the works for years, and drawing opposition all along. When the DOT first held a public hearing on it in 1997, more than 600 people sent in written comments, and 545 were completely opposed.

Three years later, opponents collected 4,700 signatures on a petition opposing the road.

Those trying to stop or change the project include supporters of the Etna Camp, a Citrus County turpentine camp now on the National Register of Historic Places that would be wiped out by the road, and the 6,000 people who get their water from the Homosassa Special Water District. If expansion is built as planned, according to a complaint filed last month, it is "nearly a statistical certainty" that a tanker truck filled with fuel or chemicals will crash someday and pollute a well field.

The DOT put Suncoast 2 on a back burner in 2008 because of the economic meltdown. It would be in mothballs today, except last year Gov. Rick Scott injected $150 million of taxpayer money into the project. Now DOT wants to let bids for construction by this summer.

Yet as with the Suncoast 1, URS has already tried to lower expectations. In 2013, URS predicted it would make $5.2 million when it opens in 2020. A year later, in 2014, URS dropped that to $3.8 million.

By 2049, the difference is stark. Its 2013 prediction of $29 million dropped to just $16 million in the 2014 forecast. An Aecom planner who worked on the Suncoast 2 projections said the 2014 numbers do take into account Citrus County's slow recovery from the mortgage meltdown. Those are the projections will be used by the state to sell bonds to finance the project, Deason said.

According to Dix, Suncoast 2 makes more sense if it's connected to other, proposed roads — Suncoast 3, 4, 5 and so forth — that ultimately connect to Jacksonville and relieve Interstate 75. But no one has planned or put up money for those other legs.

• • •

Make no mistake. Suncoast 1 has been a loser.

"If this were a stand-alone project, it would be bankrupt by now," said independent bond analyst Richard Ciccarone.

But there's a reason why the DOT can afford Suncoast and is now doubling down on its bad investment, he pointed out. It's backed by all the revenues of the state's toll road system — not just the ones from that single road. Florida's Turnpike and other big facilities, such as the Suncoast Parkway, bring in 75 percent of the system's revenue. That gives the agency some room to take risks, bond analysts said.

To the man known as the most avid supporter of both Suncoast Parkways, the roads will be a success, no matter what the financial projections say. Jim Kimbrough chairs the biggest bank in Hernando County and serves as a gubernatorial appointee to the Tampa Bay Area Regional Transportation Authority. When Suncoast 1 opened, he chaired the state Transportation Commission.

"We might not get the traffic counts for a while, but it'll get there," he said. "In my opinion, it will get there."

Researcher Caryn Baird contributed to this report. Contact Craig Pittman at craig@tampabay.com. Follow @craigtimes.