Engineering Project Case Studies | Erdman Anthony

New Expressway and Interchange

Take a quick flyover of PennDOT District 2-0’s new interchange for US Route 322 at PA 144 in Centre County.

The US 322 Potters Mills Gap project in central Pennsylvania is an important link between southeastern Pennsylvania and State College, home of Penn State University. Over the years, the highway has been widened into a four-lane expressway from the southeast. This project provided a 3.75-mile extension of the expressway tying into PA 144 and the existing two-lane section of US 322 at the western end. The overall design effort included two new interchanges, five bridges, and approximately 5,000 feet of retaining walls.

Selected to be a major subconsultant on the project team, Erdman Anthony was assigned design services for the $35 million westernmost section that includes the PA 144 interchange. Erdman Anthony also provided field survey and right-of-way plan development for the entire corridor.

Erdman Anthony’s design responsibilities included a diamond interchange with a 135-foot-long single-span bridge carrying the US 322 expressway, a 1,700-foot-long median retaining wall along the eastern approach to the interchange, 1.5 miles of new or reconstructed local roadways, and a new roundabout at the westbound ramp intersection.

By extending an important expressway corridor between State College in central Pennsylvania and the Philadelphia urban region that forms part of the northeastern megalopolis, this project enhances safety and mobility for a growing number of travelers while providing infrastructure for future statewide economic growth. 

Robert Leonard, PE
Robert Leonard, PE
 717-766-1741 x 5006