Ashford Dunwoody Road
Diverging Diamond Interchange

Ashford Dunwoody Road at I-285 is a highly congested urban interchange servicing one of the highest concentrations of commercial office space and retail shopping in the Atlanta area. It has been plagued by congestion for years with an AADT of 55,000 vehicles per day. MA was hired to find engineering solutions to the congestion along Ashford Dunwoody. Through microsimulation modeling, it was determined that a diverging diamond interchange (DDI) would provide 5-20% delay relief during the peak hours of traffic. MA was then tasked with the interchange modification report, concept development, environmental document and preliminary design. The project consisted of reconstruction of the interchange ramp termini, demolition and reconstruction of the partial cloverleaf and conversion of the existing bridge to left-side through traffic to enable the innovative DDI, all on existing right-of-way.

2012 Best Innovative Solution Award - Georgia Partnership for Transportation Quality

2012 Grand Design Award - Georgia Partnership for Transportation Quality

Highway Interchange Modification




Concept Design

Environmental Documents


Civil and Structural Engineering

Landscape Design
Diverging Diamond (Double Crossover Diamond)

Innovative Construction

New Pedestrian (ADA) Facilities

First in Georgia