Work continues to progress on a four-year, toll-funded $101.6 million project to replace two bridges on the turnpike's Northeast Extension.

The Pennsylvania Turnpike Commission is replacing the 52-year-old bridges over the Lehigh River Canal, as well as over the nearby Pohopoco Creek, with four separate structures.

The wider structures two northbound and two southbound are being built just upstream of the existing bridges between the Lehigh Tunnel and the Mahoning Valley Interchange (Exit 74) in Carbon County.

Slightly more than 30,000 vehicles, on average, travel over the bridges each day, totaling nearly 11 million cars and trucks in 2008.

Workers for general contractor Walsh Construction continued to excavate the rock slope that crosses Route 248 adjacent to the Lehigh River Bridge despite the blustery cold weather this week.

The work zone, which is located between mile markers 73 and 75, includes the new bridges, as well as work on the turnpike approaches that will eventually tie-in the new spans to the extension in the final year of construction.

Once completed, four bridges will be constructed: two of which will span the Lehigh River, and two which cross the Pohopoco Creek.

Each bridge will have two lanes.

One bridge over the Pohopoco Creek and another over the Lehigh River will carry northbound traffic, while the other two bridges, which will run parallel to the northbound traffic bridges, will handle southbound traffic.

The new dual bridges over the Lehigh River, and the historic Lehigh Canal that parallels its eastern bank, will be 1,530 feet long and rise 75 feet over the river and canal.

The bridges over the Pohopoco Creek, located north of the Lehigh River span, will be 1020 feet long and 120 feet high.

Superstructures of both new bridges will be built of pre-stressed concrete beams with reinforced concrete decks 42 feet wide in each direction.

They will include two 12-foot wide travel lanes, a six-foot wide inside shoulder and a 12-foot wide outside shoulder in each direction.

Construction of the new bridges is expected to be completed in late 2011.

At completion, Turnpike traffic will be shifted onto the new spans and demolition of the old bridges will get under way.

All work on the project is scheduled to be completed in late 2012.

In October, the Centre Street Bridge, which spans Pohopoco Creek to the Borough of Parryville, was opened after seven months and $1.7 million of reconstruction.

The Lehigh River and Pohopoco Creek Project is part of the Turnpike's self-funded, 10-Year Capital Improvement Plan that was developed to rebuild and modernize more than 545 miles of tolled highway under its jurisdiction.

It also represents a Carbon County milestone.