Pennsylvania Department of Transportation Secretary Mike Carroll and local officials held a press conference on Wednesday to highlight the department’s various projects from the 2025 season and to preview upcoming projects in 2026. 

One of the dozen or more projects they previewed is the replacement of the Commercial Street Bridge, within 1 mile of the eastern end of the Squirrel Hill Tunnel.

“This project behind me is a prime example of an investment that we’re making on a bridge that is in a main artery to the beautiful city of Pittsburgh and is traveled by more than 100,000 vehicles per day,” Carroll said. “It has certainly served this community well, but it’s time for it to be replaced.”

Construction on the original bridge began in 1948 and was completed in 1951. Since then, it has gone through three rehabilitations: in 1980, 2006 and 2012. But PennDOT officials said they must replace it because another rehabilitation project would be difficult, given the nature of the concrete the bridge is made from and the arches that support it. 

“It can no longer carry permit loads,” said District 11 Executive Jason Zang. “Permit loads are not something we think about every day, but these are extremely large loads, heavy loads, heavier than legal.”

This bridge replacement project is both sophisticated and unique. Crews will build a new bridge with steel beams brought in from Wisconsin. It will be built parallel to the existing roadway on the Parkway East. Then, in July, the old bridge will be taken down, and the new one will be slid into place.

“It’s a stunning engineering feat,” said Carroll. “It’s a stunning construction feat, and I am eager to see that all transpire next year.”

“It’s an amazing project,” said Zang. “It’s incredibly innovative, and what we’re going to do here and slide this new bridge into place in a one-month period is really something to be proud of and something incredible.”

With that time spent repairing the bridge will also come road closures. The stretch of Commercial Road that snakes underneath the bridge will be closed at the end of November for crews to set up cranes and other equipment to prepare for the demolition and replacement. That closure will last for three months. Then, in July, Interstate 376 East will close for one month to complete the project. 

PennDOT officials say while they understand the closure of the main highway artery westbound into the city will create massive delays and detours, they also strategically made the decision to shut it down in July because it is the time of year when the traffic volume is at a minimum. But they also say a partial closure of the highway would have resulted in a much longer project that could last several years, which would have created long traffic delays for a longer period of time.

“The trade-off is significant because the neighborhoods on both sides would be affected for a period measured in years instead of just the one month,” said Carroll.

“We expect it to be congested,” said Zang. “We expect it to be very challenging for everybody.”

With that in mind, PennDOT is warning drivers and residents to start planning for the month-long closure now.

“If you can work from a remote location, please do,” said Zang. “The more traffic we can get off the local roads, the better. 

Officials said until recently, projects like this one had only been done in other parts of the country, but it’s the first of this kind in western Pennsylvania.

“The PennDOT district staff, along with our industry partners, have found an innovative solution to replacing this bridge along the interstate, and to keep the public safe, reduce traffic restrictions and minimize the impact across the region,” Carroll said.

Officials advise drivers to visit PennDOT’s website for any information on closures and detours ahead of departure times to minimize traffic delays.

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