Phase I Archaeological Survey of the Cobb Galleria Pedestrian Bridge, Cobb County, Georgia.

Cobb County Department of Transportation proposes to construct a pedestrian/transit bridge across Interstate (I)-285. The bridge approach would begin at a point along an existing private roadway that services the Cobb Galleria. The bridge would span the interstate and the service interchanges for I-285 and I-75. The bridge consists of three components, a main span (Leg 1) that then splits to two separate bridges referred to as Leg 2 and Leg 3. The main span would carry both pedestrian and transit, but at a point the bridge would split with one leg of the bridge carrying only pedestrian and bicycle traffic (leg 3) to a proposed development associated with the future Braves baseball stadium (being constructed by others). The other leg of the bridge (Leg 2) would carry only transit circulators and would terminate at a T-intersection with Circle 75. Bridge construction would require between three to five bridge bents to be placed within the I-285 right-of-way (ROW).

The existing ROW along I-285 in the immediate vicinity of the bridge location is approximately 560 feet wide. To construct the bridge, approximately 16,365 square feet (.376 acre) of ROW from within the I- 285 corridor would be required.

The total bridge length across the interstate and service interchanges is approximately 1,151 feet. This total length encompasses the three independent bridges. The bridge elevation over the interstate would be approximately 40 feet in height. This height is required to consider future managed lane connectivity to and from I-75 and over I-285.

The transit travel lanes on the bridge would consist of two 12-foot wide travel lanes, one in either direction. A center planter box would be installed that is approximately 4-feet wide. On the other side of the planter box, two 5-foot wide bike lanes would be constructed, allowing for two-way bicycle traffic. The bicycle travel lanes would then be separated by a 6 to 8-inch header curb to allow for a 15-foot wide pedestrian sidewalk. The total width of the bridge would be approximately 52 to 57 feet.

Streetscaping elements are proposed for the bridge and may include plantings, benches, lighting, and a decorative noise wall along the east side of the bridge. The noise wall would be approximately 5 feet in height and topped by a transparent noise barrier that would be approximately 7 to 10 feet in height. This noise barrier material and aesthetics is subject to be modified based on funding availability.

No interstate access would be permitted to or from the pedestrian/transit bridge.

The existing roadways involved with the project include Galleria Drive, Circle 75, and I-285.

Galleria Drive is a four-lane (two in either direction) private road with 11-foot wide travel lanes. A 14- foot center turn lane varies throughout the private road. A 10-foot wide sidewalk would be constructed along the east side of Galleria Drive to connect the bridge to an existing pedestrian plaza within the Galleria. The new sidewalk would be approximately 400 feet in length. Roadway improvements to Galleria Drive in the immediately vicinity of the bridge would consist of raising the grade by approximately 1 foot to accommodate the required height of the bridge over the interstate and for the grade on the bridge to be in compliance with the American with Disabilities Act. An access agreement will be granted to Cobb County from the Galleria. There is no purchase of ROW in this area.

Circle 75 is a four-lane county road consisting of 11-foot travel lanes (two in either direction). The existing Circle 75 ROW is approximately 66 feet wide. No purchase of ROW is required at Circle 75.

Retaining walls would be added where needed along Galleria Drive and Circle 75; however, this is private and County owned ROW. An access permit would be requested from the Georgia Department of Transportation for work occurring within the I-285 ROW.