Less than eight months after the old bridge was closed in a hurry because of fear of collapse, the Pennsylvania Department of Transportation has finished building a replacement over Interstate 70 near the Washington, Pa.-South Strabane line.

The new North Main Street Bridge, located near the I-70/79 north junction, will be opened to traffic tomorrow afternoon after a 3 p.m. ribbon-cutting.

PennDOT awarded a $6.6 million emergency contract in January to raze the old span and replace it after engineers making a special inspection detected structural problems more serious than previously shown. It crossed 34 feet above I-70 at the highest point.

The North Main Street Bridge and other similar concrete box-beam bridges built in the 1960s were evaluated after a 60-ton box beam on a nearby I-70 overpass collapsed onto the highway Dec. 27, leaving five people injured.

In the aftermath, two other same-style, same-era bridges were closed on the interstate, along with about a dozen other state- and locally owned spans elsewhere, including one at the Route 422/8 interchange north of Butler.

The I-70/Lakeview Drive Bridge, where the beam fell, also is being replaced. It is to be done by Thanksgiving.

PennDOT has yet to decide what to do with the I-70/Sumney Road Bridge in a rural section of Somerset Township. It was used by fewer than 100 vehicles a day before it was closed and torn down. An alternate route exists.

The North Main Street Bridge, however, has always been a busy link between Washington and South Strabane, including access to Washington Hospital and a number of offices and businesses. The average daily traffic before closing was 9,200.

All three of the concrete box-beam bridges carrying local traffic over I-70 in Washington County had been on PennDOT's list of structurally deficient bridges for some time. PennDOT says 23 percent of its 25,300 bridges statewide are classified as structurally deficient, meaning that although they are open they are in need of major repairs or replacement.