Commercial Street Bridge replacement on pace for Parkway East closure next July

With the wind howling Wednesday afternoon after a near-freezing overnight, John Myler nearly crossed his fingers as he said the time-sensitive project to replace the Commercial Street Bridge on the Parkway East is on schedule.

As the Pennsylvania Department of Transportation’s principal assistant construction engineer for Allegheny, Beaver and Lawrence counties, it’s Myler’s job to make sure the replacement bridge crews are building in Frick Park to the left of the inbound Squirrel Hill Tunnel is ready by early July. That’s when the agency plans to close the highway for 26 days so it can demolish the old bridge and slide the new bridge into place.

The department has purposely scheduled the closure for July because it’s traditionally the least busy travel month on the highway, which carries about 100,000 vehicles a day. That means Myler has a firm deadline.

“If we have a winter like last year [when relatively mild, dry weather allowed work to continue almost uninterrupted], we’re in really good shape,” Myer said after a news conference at the construction site. “If we have a historic winter, we’re hurting.”

Construction crews have started assembling the bridge on the park floor about 25 feet from the existing bridge, working from the high end near the tunnel to low end. So far, they’ve built about an arch and a half of the four needed for the 861-foot bridge.

Motorists on the highway have faced traffic restrictions as crews built a retaining wall just outside the tunnel and had beams delivered to the site, but most of the work has been out of view. That changed about six weeks ago when the tops of huge red cranes used to lift beams into place on the new structure began protruding above the highway.

In a couple of weeks, Commercial Street and Forward Avenue, along with the Nine Mile Run Trail, will close for about three months between Whipple Street in Swisshelm Park and Summerset Drive in Squirrel Hill. That will allow contractor Fay S&B USA to build the arches on the lower end, farther from the tunnel.

When the arches are built, the road and trail will reopen while crews install the rebar and deck for the new bridge. By early June, Myler said, the new bridge will be mostly finished so that subcontractor Mammoet, a Dutch company that specializes in moving big things, can test whether the plan to use hydraulic jacks to move the new bridge into place will work.

The trail and roadway will be closed again for a couple of months while the old bridge is demolished and debris removed, then the new bridge is pushed into place. That will be a very deliberate process with jacks slowly pushing the 4 million-ton bridge about 1 foot an hour until the structure is in place.

This will be the largest off-site bridge PennDOT has built nearby and moved into place in this part of the state and one of the highest ever. In 2019, Mammoet moved two 70-foot pieces of the Shaler Street Bridge into place above Route 19/51 in Pittsburgh’s Duquesne Heights neighborhood, but those only weighed about 270 tons.

“It’s a stunning engineering feat; it’s a stunning construction feat,” PennDOT Secretary Mike Carroll said during the news conference. Carroll noted that this type of construction will close the highway for just under four weeks where traditional construction would have closed the bridge or severely limited traffic for 100,000 vehicles a day for up to four years.

The department held extensive discussions with local communities and residents about the best way to replace the bridge and chose this method. Another community meeting will be held before the full closure.

“We’re going to rip the Band-Aid off and do this,” said Jason Zang, PennDOT’s district executive. “We’re going to get this done.”

Zang encouraged commuters to consider working from home or begin finding an alternate route now to avoid the Parkway East during the July closure.

Across the three-county district this year, PennDOT started 49 projects worth $512 million. That included paving 724 miles of roads, repairing or replacing 44 bridges and remediating 42 landslides.