A new northbound bridge at Route 28's Etna interchange will fully open this afternoon, marking completion of the latest phase of a project that started more than 10 years ago.

The respite will be brief. More work is scheduled to begin in the spring, according to the Pennsylvania Department of Transportation.

The old structurally deficient mainline bridge was closed June 8 and northbound traffic was sent on a detour across the 62nd Street Bridge, along Butler Street and back to Route 28 via the Highland Park Bridge.

One lane opened on the new bridge Oct. 27.

This year's $22.5 million reconstruction was the fourth of five phases of reconstruction of the Etna interchange. When work began in August 1999 it was envisioned as a five-year, $40 million effort. Instead, funding problems and assorted delays have stretched it out to more than a decade, and more than $75 million has been spent.

The project was needed to bring the sprawling interchange up to modern safety standards and eliminate the one-lane bottlenecks for through traffic.

The fifth and final phase, estimated to cost $30 million to $40 million, will begin in the spring and continue through late fall, PennDOT spokesman Jim Struzzi said.

It will upgrade portions of the interchange that were not in the previous phases, including reconstruction and widening of northbound Route 28 from Butler Street (Exit 4) through the Sharpsburg exit (Exit 5A) to the newly opened bridge; the Sharpsburg and Route 8 exits; and Route 8 northbound from the 62nd Street Bridge to Kittanning Street.

The project calls for widening/replacement of a bridge over CSX railroad tracks, rehabilitation of two bridges on ramps that cross over Pine Creek and construction of two retaining walls.

Completion of the Etna interchange will not mark the end of traffic woes for Route 28 commuters. Still looming is major reconstruction of the section from Troy Hill to Millvale, known to some as the "death stretch."

That project will result in grade-separated interchanges at 31st and 40th streets that are designed to ease the chronic backups that occur at traffic signals at the two bridges.

To prepare for that, PennDOT recently awarded a $21.9 million contract to move the Norfolk Southern Railway tracks along Route 28 closer to the Allegheny River. The project includes a new trail bridge along the riverbank to connect the city's North Shore trail to Millvale's riverfront.

A $2.1 million project is under way to install cameras and other "intelligent transportation system" components on Route 28 and streets in Lawrenceville that might be used as alternate routes during the reconstruction.

Mr. Struzzi said the work will be divided into two phases -- the section from the Millvale Industrial Park to Millvale interchange, estimated to cost $30 million to $35 million, is expected to be under construction in early spring.

The section from Troy Hill Road to the industrial park does not have a projected start date. The estimated cost is $70 million to $90 million.

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