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 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.

Learn more about this and other improvements

9/17/2026

Traffic Alert - The Exit 16 DDI Is Now Operational; New Traffic Patterns Are In Effect

The Exit 16 DDI Is Now Operational; New Traffic Patterns Are In Effect

DATE: Thursday, September 17, 2026

The new Diverging Diamond Interchange (DDI) is now open! Traffic on U.S. Route 2/7 (U.S. 2/7) at the I-89 Exit 16 Interchange in Colchester has transitioned to the new traffic pattern.

Time lapse photo of the Exit 16 Diverging Diamond Interchange in action.

Photo courtesy of Vermont Agency of Transportation Traffic Design Engineer Josh Bloomer.

The new traffic pattern briefly shifts vehicles to the left side of the roadway as they travel through the interchange, allowing drivers turning left onto interstate entrance ramps to do so without crossing oncoming traffic. Once vehicle travel through the interchange, traffic will return to the right side of the roadway. Traffic signals will control both crossover points. To learn more about how to navigate the interchange, please review the information below.

Drivers should stay alert, slow down, and pay close attention to roadway markings, signage, traffic signals, and traffic control personnel as construction activities continue and motorists become accustomed to the new traffic patterns.

Drivers may notice longer holds on U.S. 2/7 northbound at South Park Drive and U.S. 2/7 southbound at Mountain View Drive than they experienced before the DDI opened. Those holds are intentional and are designed to regulate traffic entering the interchange, balance traffic demand from all directions, and support efficient operations throughout the Exit 16 area. The goal is not to prioritize one roadway or movement over another, but to manage traffic across the entire interchange and U.S. 2/7 corridor as efficiently as possible overall. Motorists should also expect an adjustment period as drivers become familiar with the new traffic pattern. In addition, ongoing construction activities, including periodic lane closures and traffic restrictions, may result in temporary increases in congestion during work hours as the project continues toward completion in the summer of 2027.

11/12/2026

Weekly Construction Update - Thursday, November 12, 2026

SPECIAL ANNOUNCEMENT: By the end of the week, crews will remove the existing span wires and traffic signal heads at the intersections of U.S. Route 2/7 (U.S. 2/7) with Rathe Road and Hercules Drive, and activate the new traffic signals mounted on the recently installed mast arms. The intersections will operate under temporary signal timing and phasing until next construction season, when crews will place final pavement and pavement markings and the signal timing and phasing will be updated to accommodate the final intersection layouts. Motorists should drive carefully and pay extra attention to the new signal operations.

TRAFFIC IMPACT AND DURATION: Daily, starting Monday morning, November 16, through Friday afternoon, November 20, between 9 a.m. and 3 p.m., U.S. 2/7 between South Park Drive and Mountain View Drive will be reduced to a single lane in each direction with traffic shifts. Two-way traffic will be maintained. Motorists should slow down, stay alert, and follow all traffic control devices as traffic will be shifted along U.S. 2/7 throughout the diverging diamond interchange to accommodate various construction activities.

CONSTRUCTION ACTIVITIES: Daytime work will take place between 7 a.m. and 3 p.m., starting Monday morning, November 16, through Friday afternoon, November 20. Crews will install median barrier along U.S. 2/7 within the diverging diamond interchange. Early next week, crews will install curb for the splitter island at the I-89 South on-ramp. Later next week, crews will install curb for the splitter island at the I-89 North on-ramp.

11/6/2026

Weekly Construction Update - Friday, November 6, 2026

TRAFFIC IMPACT AND DURATION: Daily, starting Monday morning, November 9, through Friday afternoon, November 13, between 9 a.m. and 3 p.m. unless otherwise noted:

Outermost lane closures on the east (northbound) side of U.S. 2/7 between South Park Drive and Mountain View Drive. Two-way traffic will be maintained.
Single-lane closure on the west (southbound) side of U.S. 2/7 between South Park Drive and Mountain View Drive. Two-way traffic will be maintained.

Possible nighttime impacts, beginning as early as Sunday night, November 8, and continuing through Friday morning, November 13, between 9 p.m. and 6 a.m.:

Single-lane closures on either side of U.S. 2/7 between South Park Drive and Mountain View Drive. Two-way traffic will be maintained.

CONSTRUCTION ACTIVITIES: Daytime work will take place between 7 a.m. and 3 p.m., starting Monday morning, November 9, through Friday afternoon, November 13. Crews will install barrier beneath the Interstate 89 (I-89) overpass between the bridge piers and the roadway on the east side under an outer lane closure. Additionally, crews will continue installing curb for the splitter islands under single-lane closures.

Night work may also take place between 9 p.m. and 6 a.m., starting as early as Sunday night, November 8, and continuing through Friday morning, November 13. Curb installation may take place along U.S. 2/7 between South Park Drive and Mountain View Drive under lane closures.

10/30/2026

Weekly Construction Update - Friday, October 30, 2026

TRAFFIC IMPACT AND DURATION: Nightly, starting Sunday night, November 1, through Friday morning, November 6, between 9 p.m. and 6 a.m. unless otherwise noted:

Single-lane closures on either side of U.S. 2/7 between South Park Drive and Mountain View Drive. Two-way traffic will be maintained.

Daily, starting Monday morning, November 2, through Friday afternoon, November 6, between 9 a.m. and 3 p.m. unless otherwise noted:

Outermost lane closures on west (southbound) side of U.S. 2/7 between South Park Drive and Mountain View Drive. Two-way traffic will be maintained.

CONSTRUCTION ACTIVITIES: Night work will take place between 9 p.m. and 6 a.m., starting Sunday night, November 2, through Friday morning, November 6. Curb installation will take place along U.S. 2/7 between South Park Drive and Mountain View Drive under lane closures.

Daytime work will take place between 7 a.m. and 3 p.m., starting Monday morning, November 2, through Friday afternoon, November 6. Crews will install barrier under the Interstate 89 (I-89) overpass between the bridge piers and the roadway, starting on the west side under outer lane closure.

10/23/2026

Weekly Construction Update - Friday, October 23, 2026

SPECIAL ANNOUNCEMENT: Today, the existing span wire and traffic signal heads at the intersection of U.S. Route 2/7 (U.S. 2/7) and Mountain View Drive/Lower Mountain View Drive will be removed, and the new mast arms and traffic signal heads will become operational.

The intersection will continue to operate under temporary signal timing and phasing. During this interim condition, motorists turning left from Lower Mountain View Drive will have a short, protected left-turn phase. Some signal equipment, including select traffic signal heads and pedestrian indicators, will remain inactive until next construction season, when the new controller cabinets are installed and final paving and pavement markings are completed. Once these final activities are complete next season, updated signal timing and phasing will be implemented. These changes will provide separate signal phases for Mountain View Drive and Lower Mountain View Drive, further improving traffic operations at the intersection.

TRAFFIC IMPACT AND DURATION: Nightly, starting Sunday night, October 25, through Tuesday morning, October 27, between 9 p.m. and 6 a.m. unless otherwise noted:

Outermost lane closures on either side of U.S. 2/7 between South Park Drive and Mountain View Drive. Two-way traffic will be maintained.

Daily, starting Monday morning, October 26, through Friday afternoon, October 30, between 9 a.m. and 3 p.m. unless otherwise noted:

Outermost lane closures on either side of U.S. 2/7 between South Park Drive and Mountain View Drive. Two-way traffic will be maintained.

CONSTRUCTION ACTIVITIES: Night work will take place between 9 p.m. and 6 a.m., starting Sunday night, October 25, through Tuesday morning, October 27. Curb installation will take place along U.S. 2/7 between South Park Drive and Mountain View Drive under outer lane closures.

Daytime work will take place between 7 a.m. and 3 p.m., starting Monday morning, October 26, through Friday afternoon, October 30. Crews will install sidewalks and stamped concrete along U.S. 2/7 between South Park Drive and Mountain View Drive under outer lane closures. Pier repairs on the Interstate 89 (I-89) overpass bridges will continue outside of the roadway on either side of U.S. 2/7.