Vermont’s First Diverging Diamond Interchange

The Vermont Agency of Transportation (VTrans) is improving the roadway along the U.S. Routes 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 project area extends from in the Colchester-Winooski town line north for approximately 1 mile to just beyond the intersection of Sunderland Woods Road at U.S. 2/7. The core of the project is to reconfigure the existing tight diamond interchange to a Diverging Diamond Interchange at I-89 Exit 16.

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Image of Interchange

Project Updates

The Exit 16 Diverging Diamond Interchange (DDI) Project Team is excited to announce that construction of the Exit 16 DDI Project is coming!

In August 2022, the Vermont Agency of Transportation awarded the construction contract for Phase 1 of the Exit 16 DDI Project to S.D. Ireland Brothers Corporation. The construction contract was awarded at an estimated cost of approximately $7.5 million. Work in Phase 1 will include utility relocation, waterline replacements, telecommunications duct bank installation, ledge removal, and the construction of the retaining walls.

The construction of Phase 1 was anticipated to begin this fall; however, the start of construction has been postponed. The postponement is due to the contractor being assigned to an emergency culvert repair/replacement project in Richmond, VT requiring staff and other resources to be redirected to that effort.

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POSTPONED - Exit 16 DDI Construction Public Meeting

The Vermont Agency of Transportation (VTrans) has POSTPONED the Construction Public Meeting for the Exit 16 Diverging Diamond Interchange (DDI) Project that was previously scheduled for Monday, October 10, 2022, at 6:30 PM.

This meeting will be rescheduled in advance of the start of construction. When the meeting is rescheduled, a project notification will be issued to our stakeholder contact list and posted here on the project website. The future meeting will include a presentation on the project overview, construction schedule and sequencing, the anticipated impacts, and information about future blasting activities with the opportunity to ask questions of the project team and contractor.

The Exit 16 DDI project includes improvements to the US Routes 2/7 corridor, in the vicinity of 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 to a Diverging Diamond Interchange (DDI) at I-89 Exit 16. The initial contract for the Exit 16 DDI project has been awarded to S.D. Ireland Brothers Corporation. The initial contract includes utility relocation, waterline replacements, telecom duct bank installation, ledge removal, and the construction of retaining walls.

If you have questions or would like additional information about the project, please reach out to the project team!

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VTrans Awards Construction Contract for the Exit 16 DDI Project

On Monday, August 22, 2022, the Vermont Agency of Transportation awarded the construction contract for Phase 1 of the Exit 16 Diverging Diamond Interchange (DDI) Project to S.D. Ireland Brothers Corporation. The construction contract was awarded at an estimated cost of approximately $7.5 million.

Work in Phase 1 will include utility relocation, waterline replacements, telecommunications duct bank installation, ledge removal, and the construction of retaining walls. Updates to the anticipated construction schedule will be developed over the upcoming weeks. Please continue to check the website for updates or sign up to receive project related announcements directly to your email!

Updated Project Schedule Announced

VTrans has announced an updated schedule for the Exit 16 Diverging Diamond Interchange (DDI) project.

Construction of the Exit 16 DDI project will be completed in two phases under two separate construction contracts which will be executed sequentially. The bid advertisement and the contract award for the first contract, Phase 1, are planned for Winter/Spring 2022. Once awarded, phase one of construction will begin, which includes utility relocation, waterline replacements, telecom duct bank installation, ledge removal, and the construction of retaining walls. Phase 1 is anticipated to be completed by Spring 2023. Phase 2 is anticipated to be bid advertised and awarded in Summer 2023 and completed by Summer 2025. Phase 2 will consist of the bulk of the roadway work including the installation of the DDI, the addition of turning lanes, and the implementation of pedestrian and bicycle accommodations.

Visit the Project Overview page for more information. 

Driving Animations

Experience Exit 16 DDI

Driving simulation traveling on US 2 West / 7 North through the DDI

Aerial view of the operating diverging diamond interchange at I-89 Exit 16

Driving simulation exiting I-89 onto US 2 East/7 South via Exit 16

Driving simulation traveling on US 2 East/7 South through the DDI

Driving simulation exiting I-89 onto US 2 West / 7 North via Exit 16