City Councilman Ken Smith said new direct ties between the I-75 freeway and the Hamilton Place area will bring "a huge improvement in traffic for the entire area."
Councilman Larry Grohn praised CBL & Associates for putting up the city's $8 million share of the $40 million project.
He said it has been 8-10 years in the making.
The council unanimously approved moving forward on the project, which will include a "flyover" to carry southbound I-75 traffic to the mall area as well as a new direct connection for those heading north.
Officials said it should help relieve congestion at the Shallowford Road exit.
Councilman Moses Freeman said it was not true that use of the $32 million in federal funds for the project would take it away from other local road needs. He said the money was for this project, and he said it could not be used elsewhere.
He said, "We would not be able to use it for the Wilcox Tunnel or any of our dream list."
Blythe Bailey, transportation director, said, "Without CBL, there would be no project."