Interstate 78 Reconstruction - Berks County Line to Route 100

County: Lehigh
Municipality: Upper Macungie and Weisenberg townships
State Route: 0078
Project Type: Roadway Reconstruction and Widening Project
MPMS Number: 92780
Proposed Construction Start: Phase 1 - 2030; Phase 2 - 2031; Phase 3 - 2033
Proposed Construction End: 2036
Last Updated: April 2026

The I-78 interstate reconstruction project in Upper Macungie and Weisenberg Townships, Lehigh County, comprises three major interstate-related improvements. These include the construction of a new interchange at the existing state route 3015 (Adams Road) over I-78, the complete reconstruction of the I-78 and Route 100 interchange, and the complete reconstruction and widening of I-78 from the Berks/Lehigh County line to the I-78 and US 22 split. The purpose of the project is to eliminate substandard features in the corridor, reduce congestion, and accommodate planned growth in the region.

The new Adams Road interchange will be a full interchange between Adams Road and I-78. It will be constructed along Adams Road between Nestle Way and state road 3022 (Old Route 22) and will include both exit and entrance ramps for eastbound and westbound I-78. The existing Adams Road Bridge over I-78 will be replaced. The project also includes the replacement of the state route 4003 (Kecks Road) bridge over Interstate 78 (phase 1).

The I-78/SR 100 interchange will be completely reconfigured into a diverging diamond interchange, with improvements extending along SR 100 from Adrienne Drive to Tilghman Street (phase 2).

I-78 will be reconstructed from the Berks/Lehigh County line to the I-78 and US 22 interchange. Interstate 78 will be widened to 6 lanes (3 eastbound and 3 westbound) from the Route 863 interchange (Exit 45) eastward (phase 3).

This section of the I-78 corridor is vital because it connects local neighborhoods and manufacturing and shipping warehouses with the rest of the Lehigh Valley and to the greater mid-Atlantic Region and beyond. The Lehigh Valley Planning Commission expects future development along this corridor to bring more homes, manufacturing, warehouses, and commercial investments, which will increase the number of vehicles of all sizes on the network of roads and highways in this area.

These improvements will support increased traffic and make travel safer, serving the community well into the future. The project is currently in preliminary design through 2027 and will be in final design through 2029. Portions of the project, including the new interchange with Adams Road, will begin construction in early 2030. The remainder of the project will be completed in phases over the next five to seven years. The I-78 Reconstruction Project is fully funded through a combination of state and federal funding.