Work will begin within days on a major reconfiguration of the cloverleaf interchange on the Parkway West at Steubenville Pike, near Robinson Town Centre.

The project will eliminate much of the lane-changing and weaving that goes on at the interchange, said Victor DeFazio, design services engineer for the Pennsylvania Department of Transportation.

The contractor on the $13.8 million Route 22/30/60 project will remove two curving ramps that currently take Steubenville Pike traffic onto the parkway. Both funnel motorists onto the parkway just ahead of exit ramps, causing a dicey tango between those entering and those trying to leave the highway.

When the project is finished in November 2010, Steubenville Pike motorists going to the parkway will use ramps that connect to the highway beyond the exit ramps, eliminating the mixing of vehicles slowing down to exit and those accelerating to enter the parkway.

"Cloverleaf interchanges are kind of outdated. They work well under really low volumes of traffic," Mr. DeFazio said. With the heavy traffic generated by Robinson Town Centre, the Pointe at North Fayette and other retail centers in the booming area, "there's a lot of weaving and crisscrossing," he said.

The project also will bring full lighting to the interchange, repairs to the bridges that carry Steubenville Pike and Summit Park Drive over the parkway and resurfacing or reconstruction of ramps, the parkway and the pike.

Two new traffic signals will be installed, at new spurs to be built from Steubenville Pike to parkway on-ramps, and six existing signals near the interchange -- five on Steubenville Pike and one on Campbells Run Road -- will be better synchronized, Mr. DeFazio said.

New signs also will be installed as part of the work, to be done by Gulisek Construction of Mount Pleasant.

The project is one of several that will upgrade the parkway in anticipation of its redesignation as Interstate 376, said Cheryl Moon-Sirianni, PennDOT assistant executive for design.

The designation would extend the I-376 designation from its current terminus in Downtown Pittsburgh to include the Parkway West, Airport Expressway and Beaver Valley Expressway.

The interchange project will cause a variety of traffic restrictions, including lane restrictions on Steubenville Pike, ramp closings and, eventually, possible overnight closures of the parkway, Ms. Moon-Sirianni said.

It will be the first major transportation project funded by the federal economic stimulus program to start construction in Allegheny County.