A nearly 7-mile stretch of the Pennsylvania Turnpike in Pine will be rebuilt from the ground up starting this fall.

The project will include widening the highway to six lanes and replacing four bridges, and will take about three years.

"When we're done, there will be nothing old out there," said Brad Heigel, total reconstruction manager for the turnpike commission.

Joseph B. Fay Co. of West Deer submitted an apparent low bid of $113.2 million last week, well below the commission's estimate that the work would cost more than $150 million.

The project will widen the turnpike from near the existing Warrendale toll plaza at mile 31 to the Willow Run viaduct at mile 37.8, where the mainline will return to four lanes heading east, he said.

As part of the project, two curves that don't meet current highway engineering standards will be straightened.

Four bridges -- over Warrendale-Bakerstown Road, Graham Road, Pearce Mill Road and Old State Road -- will be replaced, and that work will require closing of Graham and Old State roads. The other two roads will mostly remain open during the construction, Mr. Heigel said.

He said plans call for maintaining four lanes of traffic in the work zone during peak travel times, with some single-lane patterns at night and during the winter.

Mr. Heigel said the turnpike commission worked closely with Pine residents to mitigate the impact of construction. It will build a stormwater management plant and basins, and provide property owners along the highway with seedlings to replace vegetation that is destroyed during the project.

The turnpike also has agreed to extend a trail along Graham Road, he said.

The project is among several improvements being made in Western Pennsylvania. Full-depth reconstruction of miles zero to 10 moving east from the Ohio line is near completion. The turnpike is preparing for another full-depth reconstruction between the Irwin and New Stanton exits, and is replacing the bridge over the Allegheny River with two three-lane spans, due for completion next year.

Also, the New Stanton service plaza, serving westbound travelers, reopens at 8 a.m. tomorrow after a $5.9 million reconstruction. It has been closed since September.