TRENTON, N.J. (CBSNewYork/AP) — Frustrated commuters will be glad to hear the massive work to widen a stretch of New Jersey Turnpike is closer to its end than its start.

Billed as the biggest ongoing roadway project in the United States, the undertaking will transform the turnpike into a 12-lane highway from the Pennsylvania Turnpike Connector at Exit 6 in Burlington County to Exit 9 in New Brunswick, where it is already that wide.

Trucks and buses will be restricted to the three outer lanes in each direction; only cars will be allowed in the three inside lanes in each direction.

Currently, about 130,000 vehicles a day use the 35-mile turnpike stretch in the work zone.

With a price tag of $2.5 billion — all of it from tolls — the widening work has created thousands of jobs on and off site since work began in 2009 and is costlier than any individual highway project that was undertaken with federal stimulus funding.

The Turnpike Authority’s chief engineer, Rich Raczynski, says the project is two-thirds complete and on target to be finished by fall 2014.

The impetus for the widening, dating back nearly a decade, was recurring bottlenecks at Exit 8A, where the highway goes from 10 southbound lanes to six and vice versa on the northbound side.

Anyone driving where construction is under way will find it in different stages of completion in a random pattern.

It was planned that way.

As Raczynski explained it, instead of seeking permits, acquiring land, and awarding contracts in stages, authority officials moved to do all three simultaneously.

So, when everything was ready in a designated zone, work would begin immediately.

“We picked up maybe two years on this project,” Raczynski said. “We wanted to accelerate this project.”

A fourth factor in play – moving three gas and oil pipelines that run parallel to the turnpike – also fell into place in a timely fashion.

“The (utility) companies did an extremely efficient job relocating the pipelines,” Raczynski said.

Actual planning for the project dates to 2004, and Raczynski said the intervening financial crisis had worked in the authority’s favor.

“The economic collapse helped us,” he said. “The heavy-construction industry in the state of New Jersey basically dried up, and we were the only ones pushing work out at the time.

“When you get contractors who are desperate for work, they really sharpen their pencils,” Raczynski said. “We’ve been averaging 20 percent below our estimates with the bids we’ve been getting. The actual project cost right now is lower than we anticipated.”

The remaining work will unfold in various stages.

This month, the northbound split at Exit 8A was moved two miles north for work to widen the outside lanes from two to three. The southbound merge will follow soon.

Once all the outer lane sections are joined and paved, the six inner lanes will be closed for repaving and installation of electronic traffic-monitoring equipment. That work is expected in spring 2014.

“That entire section of the turnpike will be new roadway,” said John Keller, the authority’s supervising engineer.

A half-dozen cranes towering over the highway announce the start of the project at Exit 6.

This is one of the more complicated sections because of the intersection with the Pennsylvania Turnpike connector, said field project manager Ralph Csogi, who is responsible for the first six miles of the expansion.

Currently, four ramps, including two flyovers, connect the turnpike and the extension. With the widening, the number will grow to eight. Motorists are already using one of the new flyovers, opened so an old one could be torn down. Nearby, local road bridges have had to be removed and rebuilt, or will soon be.

At the mazelike Exit 6 site last week, workers were busy laying steel on a new ramp while traffic flowed beneath. Other crews poured concrete for supports and built retaining walls for another new ramp.

“Everyone tries to set their steel before winter,” said Gerald E. Arters Jr., resident engineer for that work sector, saying that clears the way for workers to do the preparation work for pouring concrete in the spring.

“We really try to minimize interference with traffic by working over and around it,” said Michael Poole, assistant resident engineer.

He acknowledged backups happen but stressed that lane closures are planned and limited to only one sector at a time, weather permitting.

“You have 26 contractors competing for lane closures,” Poole said.

Arters, who was clearly delighted to show off the work that has been done or is under way, said he had never seen anything like the turnpike widening in his 22 years in the business.

“This is a project of a lifetime,” he said.

For his part, Raczynski, the chief engineer, is not buying predictions that adding lanes will not reduce congestion.

Some transportation experts have raised that scenario based on a highway engineering phenomenon known as “induced demand,” the tendency for new lanes to attract new drivers. Human nature and traffic science make it inevitable, the experts have said.

Raczynski said the existing turnpike congestion had forced traffic onto local roads, causing backups and increasing pollution.

He expects the expansion to draw that traffic back to the turnpike, increasing the number of vehicles on it.

“But,” Raczynski added, “with the improvements we’re making, we’ll be able to move that traffic.”

Have you been frustrated with your commute on the New Jersey Turnpike? Leave your comments below…

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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