Site work and paving for a bridge / tunnel in North Brunswick, New Jersey. Conceptual plans call for site work for a bridge / tunnel; and for paving for a bridge / tunnel.

Improvements will help relieve congestion at Route 1 from the “Dinky” railroad bridge to approximately Plainsboro Road by increasing the number of travel lanes from 3 to 4 lanes per direction on Route 1; provide shoulders, deceleration lanes, acceleration lanes, and turn lanes along the corridor for turning vehicles; widen Washington Road at Route 1 to relocate the merge of the 2-lane circle into a single Washington Road lane out of the intersection; increase the Route 1 southbound to Fisher Place jughandle turn; modify existing 3-phase signal at Route 1 and Harrison St. intersection to a 2-phase signal; and provide a Route 1 cross section with 4 lanes per direction at the Millstone River Bridge. This project in West Windsor (Mercer County) and Plainsboro (Middlesex County) is a derivative of the former Rt. 1/CR 571 Penns Neck project (DB #031). The magnitude and scope of work for the Rt. 1 Alexander Rd to Mapleton Rd project is greatly reduced from the Penns Neck project ($150 M vs. $35 M). County : Mercer, Middlesex Municipality: West Windsor Twp, Plainsboro Mileposts: 10.8 - 12.07 As of July 17 , 2025, the project is in Conceptual status. Anticipated letting Year is 2031. NJDOT - Route 1, Alexander Road to Mapleton Road *Project information has been obtained through a public state transportation improvement plan (STIP). A STIP is a financial schedule for short- and long-range projects which is updated regularly. Information listed in the STIP often evolves based on funding availability. The project details, including timeline and value, are subject to change. The content management team will continue to pursue additional details as they become available.