SR 31 currently consists of a four-lane typical section with depressed median, rural shoulders and no left-turn lanes at the on-ramp intersections. The proposed project would maintain two through lanes in each direction and add dual westbound left-turn lanes for the southbound on-ramp and also add an eastbound left-turn lane for the northbound on-ramp. The proposed section will have urban shoulders including curb and gutter and sidewalk and will have a raised median with grass and/or concrete. In order to comply with GDOT standards of access control, a two-lane frontage road will be constructed on the north and south side of SR 31 to provide access to the existing businesses located on each side of the roadway. Eliminating all other drives between I-75 and these frontage road intersections will provide approximately 1,000 feet of access control.
The proposed project consists of improvements to the interchange of I-75 at SR 31. These improvements extend along SR 31 from Hart Road (approximately 1,100 feet west of the southbound on/off ramp intersection) to approximately 1,800 feet east of the northbound on/off ramp intersection. Improvements along I-75 consist of the reconstruction of the entrance and exit ramps to/from SR 31.
The entrance and exit ramps to and from I-75 at SR 31 would be upgraded as part of the project. All existing ramps are a single lane. The improvements on the entrance ramps would include an additional lane to accommodate the dual westbound left-turn lanes from SR 31. Improvements to the exit ramps would include additional turn lanes, additional storage as well as improved signage and sight distance from the Interstate. The northbound exit ramp will have a single left/dual right configuration. The southbound exit ramp will have a dual left/single right configuration. All ramp convergence/divergence points on I-75 will accommodate the future fourth lane on I-75 northbound and southbound and will tie at the following distances from the centerline of SR 31:
Currently the I-75 interchange approaches on SR 31 are composed of two lanes in each direction separated by a 36-foot wide depressed median. The existing twin bridges over I-75 are two lanes wide each carrying the east and westbound traffic with no separate turn lanes provided on the 3 bridge deck. The project will replace the twin bridges with a new single structure that will provide two lanes in each direction with a double left-turn lane for westbound traffic entering I-75 southbound and a single left-turn lane for eastbound traffic entering I-75 northbound making the new bridge 7-lanes wide. The new bridge will have 8’- 8 ½” wide outside shoulders and the opposing lanes will be separated by a 4-foot wide raised median. The new bridge will be constructed on vertical alignment which meets the proposed design speed of 45 mph creating a need for raising the grade of SR 31 through the interchange area.
Help us to continue to make advances in research, stewardship, and bringing the past to life. No matter the size of the gift, your contribution will directly support groundbreaking archaeological research through sustaining student and outreach programs, and technological innovations. To make a secure gift online to the Archaeology Lab Fund, CLICK HERE.