The Georgia Department of Transportation (GDOT) selected the design-build (D-B) team of Archer Western Contractors and Heath & Lineback Engineers, Inc. (A BCC Company) to complete the system-to-system interchange of GA 400 with I-85 in Atlanta, Georgia. Originally built in the 1990s, the interchange was not ‘complete’ in that not all ramps were included. These new ramps provide I-85 southbound traffic with direct access to GA 400 northbound and also give GA 400 southbound motorists a direct ramp to I-85 northbound. Significant traffic growth and projections for future demand made it vital to add these ramps – under the constraint of keeping the existing interchange in service. The project also included the first nature trail built by GDOT.

GDOT elected to use the Design-Build (D-B) procurement method for the project. This represented an early venture for the Department into managing and completing such a major project using the D-B methodology. It was apparent that success would be achieved by fostering a spirit of partnership between the key players.

The project included construction of two ramps, almost two miles of roadway, and four bridge structures. Our team focused on finding the most efficient design and construction methods for the four bridges that represented the majority of the project cost. One of the bridges was almost a mile in length. One significant saving was a geometry modification that saved almost 650 feet of bridge length as compared to the costing ‘base’ plans. As the design developed, we partnered with the Department to find construction solutions that eliminated several potentially expensive utility relocations – saving time, money, and disruption to the traveling public.

Through local resident input, the project was expanded to include a ½ mile recreational trail (North Fork Creekside Trail) along the banks of North Fork Peachtree Creek and through the urban forest within the broad tract of right-of-way available at the interchange. The trail includes a 165-foot clear span bridge over the creek, three minor stream crossings, and several walls built to avoid unsightly cut and fill slopes. The trail is landscaped with native Georgia species. Designed by H&L, this is the first nature trail built by the Georgia Department of Transportation.

Bringing the Archer Western/H&L prior knowledge of the D-B method into partnership with GDOT to meet their policies and procedures provided the opportunity for all parties to learn and together build a winning project. H&L was responsible for design of roadway, bridge, and trail as well as management and coordination of all required design support services including survey, traffic, geotechnical, and subsurface utility engineering (SUE).