Dale said GDOT does not enjoy making these hard choices. “And I think that’s sort of a misconception — that this is something that we do without feeling and we just do.”

In this case, Dale said it is absolutely necessary. “We want it to be part of an ongoing Express Lanes system in the metro area,” Dale explained. New such lanes along I-285, I-85, and GA-400 would be double and separate in each direction. They would not be reversible like the lanes along I-75 on both sides of town. The GA-400 lanes would go from I-285 to McFarland Pkwy. and the I-285 lanes would reside in all directions anywhere north of I-20. Construction for the GA-400 lanes will not begin until around 2021 and may not conclude until 2024.

» RELATED: North metro Atlanta mayors propose east-west transit plan

Dale and Arum discussed how the I-285/GA-400 corridor, an area already carved up for the new interchange GDOT is building, is chock full of both businesses and residences. "You have some pretty densely-populated residential communities that are set up alongside of the interstate — not a great scenario for avoiding trying to take property," Dale said.

This, again, brings up a real problem for the desirable living places in Atlanta. More people bring more traffic. More people galvanize a need for more housing. More traffic means a need for bigger roads. The construction of bigger roads sometimes interferes with said housing. And an increase in people brings the increased need for commercial areas. And so on and so on.

As tastes and demands have changed, the “live, work, play” concept has made popular both condos and townhomes that are near both public transit and places to, well, do life. Compressing living spaces in convenient areas can free up more room for development and roads and decrease traffic.

On Arum's show, Dale quickly outlined GDOT's Major Mobility Investment Program, a cadre of 11 projects statewide that aim to decrease traffic congestion by 5% by 2030. That's a 5% decrease statewide, not just in those 11 zones, so the improvements are significant. But they come not only at a significant monetary cost, but possibly a residential one.

Looking ahead, the idea of traditional, spread-out subdivisions in highly populated areas works against the efficient expansion of roads, highways and mass transit. Just as the car culture must change at least slightly, so must residential culture. This isn't a call to action for all situations. But this notion is something to consider in both city-planning and life-planning moving forward in Metro Atlanta.

» RELATED: Federal budget deal allows Georgia DOT to catch up on road work

Doug Turnbull, the PM drive Skycopter anchor for Triple Team Traffic on News 95-5 FM and AM-750 WSB, is the Gridlock Guy. He also writes a traffic blog and hosts a podcast with Smilin’ Mark McKay on wsbradio.com. Contact him at Doug.Turnbull@coxinc.com.