Pieces of concrete have been crumbling and falling from the South Street bridge for years, so the state Transportation Department decided to demolish the span and build a new one.
Approximately 23,000 vehicles used the bridge each weekday.
The project pricetag is $67 million - about 80 percent to be paid for with federal dollars.
The bridge spans Interstate 76 - the Schuylkill Expressway - and the Schuylkill River. It is also a link to several major hospitals in West Philadelphia.