PennDOT performs major test for upcoming Commercial Street bridge replacement project. Here's what to know.

It was a big day for PennDOT as crews performed a major test for the upcoming replacement of the Commercial Street bridge on the Parkway East. 

You could not have blamed the folks at PennDOT if they had some butterflies to start the day as they prepared to move a bridge that weighs 22 million pounds.

For safety, crews closed Commercial Street and the Nine Mile Run trail, which run underneath Interstate 376, as tests on Thursday made sure things will work next month for the big move while the Parkway East is closed.

PennDOT senior assistant construction manager John Myler said that crews planned to test all of the required equipment for moving the bridge next month.

"The overall weight of the completed bridge is 22 million pounds," Myler said. "The bridge is just over around 850 feet in length."

The company that has installed its red moving jacks at the base of the bridge specializes in moving very big things, and while PennDOT has moved completed bridges before, Myler says this was the first time a structure of this size and scale was moved within the state. 

The goal of the test was to lift the bridge with 42 jacks, get it off its temporary bearing, move it roughly 5 feet toward the existing bridge and then back. Thursday was all about feasibility.

"We just don't want any hiccups," said PennDOT District 11 executive Jason Zang. "Once the Parkway is closed, the name of the game is time and doing this as quickly as we can."

While Commercial Street was temporarily closed, traffic on the Parkway East was not impacted on Thursday.

Commercial Street was expected to reopen around 4 p.m. before it closes again on Monday, but PennDOT pushed the closure back to 9 p.m. It will remain closed through early August when the new bridge is installed.