Fay, S&B USA Construction (Fay), a Pittsburgh-based firm specializing in heavy highway and heavy civil construction in the Mid-Atlantic region, re-opened the I-376 Commercial Street Bridge in Pittsburgh for the Pennsylvania Department of Transportation (PennDOT) on July 27, 17 days after closing it and a week ahead of PennDOT's maximum deadline of Aug. 3.
During the closure, Fay demolished the existing bridge and completed a lateral slide of the new bridge into place using accelerated bridge construction (ABC) methods.
Fay constructed the new bridge directly beside the existing 75-year-old bridge. Using ABC techniques reduced more than four years of long-term lane closures and restrictions on I-376 to a fewer than three-week closure of part of the corridor between the Edgewood/Swissvale (Exit 77) interchange and the Squirrel Hill Tunnel in Edgewood and Swissvale boroughs and the city of Pittsburgh. I-376 is one of the most heavily traveled highways in western Pennsylvania, supporting more than 100,000 vehicles per day.
"This is Fay's 10th ABC project and marks the largest one in Fay's nearly 80-year history," said Ryan Surrena, president of Fay. "We thank PennDOT for the confidence in our team to deliver the largest lateral bridge slide in Pennsylvania, as well as the traveling public and regional businesses for their patience as we constructed and slid the modern structure into position. From day one of work, PennDOT and Fay shared a common vision to deliver this project safely, quickly and precisely."
Completed in 1951, the original Commercial Street Bridge was scheduled for replacement because it had reached the end of its service life and could no longer carry permit loads. Fay's demolition team dismantled the original bridge in six days using conventional demolition methods to remove the concrete deck, parapets and overhangs, followed by a controlled implosion to safely drop the rest of the concrete structure.
Fay, S&B USA Construction
Following a conventional demolition of the bridge deck, Fay performed a controlled implosion to drop the remainder of the former Commercial Street Bridge in Pittsburgh on July 16, 2026.
Fay built the new arched delta frame structure directly beside the previous bridge over approximately two years in a $95 million project. The new structure features three spans and seven 825-linear-ft. girder lines. Each delta frame consists of seven pieces of steel ranging in weight from 25,000-80,000 lbs.. The largest piece is a 163-ft. header beam.
Designed to modern highway standards for safety and mobility, the new bridge has standard 4-ft.-wide median shoulders and 12-ft.-wide right shoulders to allow disabled vehicles to be moved to the side and provide space for emergency vehicle passage and future maintenance.
During construction, intermittent lane closures and restrictions were only required for delivery of the steel girders, work on overhead signage and other supporting work.
Fay, S&B USA Construction
Steel girders and arched delta frames are erected for the new I-376 Commercial Street Bridge in Pittsburgh in the fall 2025.
Mammoet, the Netherlands-based heavy-lifting specialist, lifted and slid the 22-million-lb. (11,000 ton) structure 102 ft. from its temporary foundations to new permanent foundations across four continuous rails using 42 of the firm's proprietary skidding system jacks. The slide took less than 10 hours to complete. According to Mammoet, the Commercial Street Bridge was the heaviest bridge the company has moved in the United States.
Fay, S&B USA Construction
The new Commercial Street Bridge on July 20, 2026, after it was slid into place.
While the new bridge is open to traffic, the project will continue into summer 2027 as Fay returns Commercial Street below the bridge to its original alignment, removes the temporary bridge foundations and clears all remaining debris. Fay also will restore Frick Park's Nine Mile Run stream and hiking trail, and plant approximately 5,000 new trees and shrubs to restore the project site.
