Phase 2 Construction
Starting this Week, Contractor On-Site Presence on the Exit 16 Diverging Diamond Interchange Project
DATE: Tuesday, August 26, 2025
Project Update
The contractor, S.D. Ireland, plans to begin mobilizing to the project area as early as this week. Crews may start installing construction signage throughout the project limits this week into next in preparation for the start of major construction activities. Sign installation will occur predominantly outside the roadway; however, temporary shoulder or lane closures may be necessary on U.S. Route 2/7 (U.S. 2/7) north of Sunderland Woods Road and south of the Colchester/Winooski town line.
Major construction activities are not expected to begin until after Labor Day, as early as mid-September. The project team will have more information regarding the official start date and anticipated traffic impacts of major construction activities after the baseline construction schedule and traffic control plan have been approved. Additional project updates will be issued in the upcoming weeks.
Phase 2 Construction
The Vermont Agency of Transportation is improving the roadway along the U.S. Route 2/7 (U.S. 2/7) corridor, in the vicinity of Interstate 89 (I-89) Exit 16, to enhance mobility and safety in Colchester, Vermont. The core of the project is to reconfigure the existing tight diamond interchange into a Diverging Diamond Interchange (DDI) at I-89 Exit 16. Phase 2 construction will begin this fall and be completed in the summer of 2027. This phase will focus on roadway construction, including:
- the installation of the DDI,
- adding turn lanes at the Mountain View Drive, Hercules Drive, and Rathe Road intersections,
- modernizing traffic signals at South Park Drive, the I-89 Exit 16 Interchange, Mountain View Drive, Hercules Drive, Rathe Road, and Tigan Street, and,
- further enhancing pedestrian and bicycle accommodations.
What is a Diverging Diamond Interchange?
A DDI is an innovative, modern interchange design that can relieve traffic congestion and improve safety for drivers, bicyclists, and pedestrians. In a DDI, traffic crosses to the left side of the roadway, allowing traffic to make a left onto the interstate on-ramps without crossing oncoming traffic. The reduction of conflict points eliminates potential user collisions, thus improving safety and vehicle throughput. With left turn movements operating freely within the DDI, the traffic signals no longer require protected left turn phasing, improving overall traffic operations at the interchange. Additional benefits include reducing driver discomfort, fuel consumption, and lost time. The DDI’s channelizing raised islands significantly reduce the number of wrong-way entrances onto the interstate. The raised islands also create short crossing distances, which increases overall safety for non-motorized users such as pedestrians and bicyclists.
Stay Informed
The project team will provide additional project updates in the coming weeks as the start of construction approaches. Throughout construction, weekly Construction Updates and supplemental Traffic Alerts will be issued. Want to join our email list to receive future project updates? Send us an email!