Mitchell Street serves as an artery connecting Northside Drive with downtown Atlanta. The road also functions in a local capacity as part of the City grid system. Ten railroad tracks run underneath the bridge, with plans to rework the tracks for future passenger rail facilities and add a north-south main track. The bridge was structurally and functionally inadequate and eventually, in 2008, it was closed by the Georgia Department of Transportation (GDOT) because of concerns that it would fail under heavy traffic. Heath & Lineback was retained to design a replacement.
The bridge and its approaches include interfaces with a system of streets, viaducts, retaining walls, sidewalks, public and private utilities, street lighting, railroads, storm drainage and traffic signals.
Maintaining grade on the approaches was a vital consideration in preserving connectivity with side streets at a reasonable cost. Providing long clear spans over all railroad tracks was a requirement of Norfolk Southern Railroad because this provided the flexibility for future rail tracks. Our solution was based on the design of long span, welded plate girders, tightly spaced to minimize construction depth over the tracks. Sanitary and storm drainage, some very old, were retained where possible and relocated/replaced as necessary.
Archer Western Contractors bid the work in 2009 and the bridge was opened in 2013, providing two traffic lanes, bicycle lanes, paving, and sidewalks.