Route 378/Hill to Hill Bridge Reconstruction Project

County: Lehigh and Northampton
Municipality: City of Bethlehem 
State Route: 0378
Local Name: Hill to Hill Bridge
Project Type: Bridge Rehabilitation
MPMS Number: 93630
Proposed Construction Start: Fall 2026
Proposed Construction End: Summer 2030
Last Updated: June 2026

The Route 378 Hill-to-Hill Bridge Rehabilitation project is finalizing design, marking a major step toward improving safety, mobility, and structural condition while preserving Bethlehem’s historic character. This federally funded project addresses structural deterioration, traffic congestion, and multimodal needs while minimizing impacts to natural and cultural resources.

Key goals for this project, identified through extensive stakeholder engagement, include maintaining four lanes of traffic during week day peak hours as much as possible, improving South Bethlehem’s 2nd Street connection to Route 378, and ensuring future improvements are not precluded.

Key features of the project include:

Rehabilitating the Hill-to-Hill Bridge

Repairs to the City of Bethlehem’s Main Street and Spring Street Ramps

Operational improvements on the south side of the bridge

Adding two sign structures north of the project to alert drivers that the Spur Route Expressway ends.

South side operational improvements include adding a second southbound left turn lane at the 2nd Street Ramp signal. The 3rd Street intersection with Route 378 will be reconstructed adding a southbound right turn lane and improving the geometry of the intersection with minimal impacts to the adjacent historic properties.

To allow for these improvements, the south end of the bridge is being widened via a new parallel bridge to carry northbound traffic. This will allow the south end of the existing bridge to accommodate only southbound traffic including adding the southbound turn lane and shoulders. This parallel structure will tie into the Hill-to-Hill Bridge near its northern truss, preserving the iconic Hudson Trusses and the bridge’s historic character.

Other improvements (requested by stakeholders) in South Bethlehem include adding a one way connection from 2nd Street to the 2nd Street Ramp to northbound Route 378 allowing improved traffic flow especially at the conclusion of local events.

Construction is anticipated to begin in late 2026.