Figure D-3: Minimum vertical clearance accommodated by raising bridge cap elevation above surface street elevations
HORIZONTAL CLEARANCES When originally constructed in the 1950’s, the Atlanta North-South Expressway (now the Downtown Connector) included six travel lanes, three in each direction, with curb & gutter, raised median and 10.5-foot shoulders. In the 1980’s, the roadway was widened with the construction plans showing a proposed ten-lane typical section comprised of four general-purpose lanes plus one High Occupancy Vehicle (HOV) lane in each direction. The HOV lane was separated with a 4-foot buffer and each direction included a 12 foot inside shoulder and 14 foot outside shoulder. These shoulder widths are compliant with current design standards. Based on historical aerial photography, construction of the widened Downtown Connector took place in the late 1980’s. A subsequent project restriped the Downtown Connector, adding an additional general-purpose lane in each direction. It is unclear when this project was implemented. It appears the additional lanes may have been present in the late 1990’s and are clear on aerial photography from 2002. To accommodate the additional lane in each direction, the four-foot buffer between the HOV lane and general-purpose lanes was removed and the inside and outside shoulder widths were reduced. The as-
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