Interstate 85 (I-85)

The Interstate 85 (I-85) Express lanes expansion project, being undertaken in Gwinnett County, Georgia, US, is aimed at managing the growing traffic in the state.

The $178m expansion project will expand the existing high-occupancy toll (HOT) lanes to provide a more dependable, free-flow commute option to balance the multimodal approach. It also expected to offer congestion relief for more than 263,000 vehicles a day.

Being undertaken by Georgia Department of Transportation (GDOT), project construction started in August 2016 and is expected to be completed in mid-2018.

Upon completion, the tolling system on the newly expanded road will be managed by State Road and Tollway Authority (STRA).

I-85 express lanes expansion project background and benefits

Opened in 2011, the existing 16 miles (25.7km) of I-85 HOT lanes run from northern Gwinnett to DeKalb County. The lanes are part of the Georgia Express Lanes system, which runs parallel to existing interstates and offers congestion relief on some of the busiest corridors in the state.

"The $178m expansion project will expand the existing high-occupancy toll (HOT) lanes to provide a more dependable, free-flow commute option to balance the multimodal approach."

Extension of the HOT lanes is expected to ease traffic flow, and provide options for motorists and registered vanpool users. It will also provide reliable trip times, create new jobs and bring economic benefits to the residents of the region.

GDOT initiated public information open house for providing an opportunity to view the updated proposal on the road expansion project in September 2014. Environmental approval for the project was granted in April 2015.

I-85 express lanes expansion project details

The expansion involves addition of ten miles (16.09km) of new lanes to the north of the existing I-85 Express lanes. One northbound and one southbound lane will be added from the existing express lanes from Old Peachtree Road to Hamilton Mill Road in Gwinnett County.

The project will also involve resurfacing of existing travel lanes and construction of two new auxiliary lanes northbound between GA 20 and the Gravel Springs Road overpass and southbound between GA 20 and GA 317/Lawrenceville-Suwanee Road.

The auxiliary lanes constructed between on and off ramps will enable local traffic to travel without entering the I-85 mainline.

The project also includes extension of the southbound bridge and construction of a new northbound bridge at the I-85/I-985 interchange to facilitate future improvements to interstate highway I-985. It will also include the widening and addition of a third general-purpose lane from the existing I-985 interchange to SR 211.

Construction on I-85 express lanes expansion

The construction works include removing approximately a million yards of dirt, building of 13 bridges along the road and construction of 23 retaining walls. The construction is divided into five phases to be completed within 36 months.

The project is expected to require the use of 350,000t of asphalt, 54,000 linear feet (LF) of storm drain pipe, 55,000LF of guardrail, and 45,000LF of concrete barrier walls. It will also include the addition of 33 new overhead signs along the road.

Contractors involved

The $147m construction contract for the extension project was awarded to C.W. Matthew Contracting in July 2015. The construction is also being supported by 20 other subcontractors.

ARCADIS was contracted to provide design services for the project.