State officials have taken the next step forward with improvements to the I-75 interchange at Hwy. 20/81 in McDonough (Exit 218).
The Georgia Department of Transportation announced Aug. 4 that a contract has been awarded to CMES, Inc. of Norcross for $5.2 million to convert the current interchange into a diverging diamond configuration.
Also called a double crossover diamond interchange, this configuration is set up so that the two directions of traffic on the highway cross to the opposite side on both sides of the bridge at the interstate. Some experts say that it is easy to navigate, eliminates last-minute lane changes, and provides better sight distance at turns, resulting in fewer crashes. It also reduces congestion and better moves high volumes of traffic without the need to increase the number of lanes in an interchange.
Sound confusing? Google “diverging diamond interchange animation” and a two-minute YouTube video makes it quite clear.
“The diverging diamond configuration provides an efficient solution to the current issue of heavy left-turn volumes currently experienced at the interchange,” according to the Georgia DOT statement. “It will allow traffic to cross to the opposite side on both sides of the bridge, allowing free-flowing left turns onto the I-75 ramps. This will eliminate current back-ups in the left-turn lanes at the signals, accommodating the high left-turn volume but with fewer lanes. “
Georgia DOT engineers are currently scheduling pre-construction meetings with CMES, Inc. and its subcontractors. At one of these meetings, they will set the anticipated start date for construction. The contract stipulates that construction must be completed by the end of spring, 2022.
The project will include short-term temporary closures of the I-75 overpass at certain points during the construction. According to project engineers, the closures will not exceed more than three or four days over an extended weekend. At these times, a detour utilizing I-75 will be installed. Georgia DOT will announce these closures and post signage in advance to alert motorists to the situation. In addition, pedestrian access to the bridge will be closed for a limited period during the construction.
Local drivers and commercial vehicle drivers who frequently utilize the interchange are encouraged to follow the Georgia DOT-West social media (Facebook, Twitter) pages for up-to-date announcements regarding this project.
