I-75 and I-675 interchange tricky, especially for truckers in the rain

The I-75 and I-675 interchange has become the Bermuda Triangle of Metro Atlanta traffic. This trend seemed to coincide with the opening of the South Metro Express Lanes, Georgia’s first reversible toll lane system, in early 2017. The new double-lane system necessitated a redesign of this two-interstate interchange in Stockbridge and prompted the removal of trees and vegetation in the area. This has helped make navigating this juncture harder.

If odds makers weighed in on such things, they would probably assign 2:1 or 3:1 odds on a tractor trailer wrecking in the I-75/I-675 interchange when rain falls. Those odds would be even higher on the southbound side of I-75, in the curve before I-675 merges in. The road seemingly becomes like ice in the rain and big freight vehicles often slide off the right side of the road. Some big rigs flip when this happens, extending the time of the cleanup.

We have seen crash patterns in certain areas over short periods of time. Construction is often the culprit when a string of wrecks occur in the same place. Such was the case on I-285 at Flat Shoals in DeKalb two years ago or is the case now in the I-285/GA-400 interchange. Changes to any variable in a traffic environment tend to cause more wrecks. Lane shifts, narrow shoulders, slimmer travel lanes, displaced ramps - these all cause the need for different maneuvers, which create conflict. And this, too, was the case on I-75 through Henry County, as crews built those Express Lanes.

But the big work zone in Stockbridge and McDonough concluded over three years ago and crashes keep occurring, especially with tractor trailers, especially in the rain, and especially on I-75/southbound right before the I-675 merge. Why is that?

Truckers in the area have told the WSB Traffic Team that the lack of trees in the median and the unearthed clay from the previous work zone make the area treacherous in rainy conditions. With no roots in that dirt to hold it in and with the topsoil being looser, rain can easily wash a film of it onto the lanes of I-75.

Trucks have the most crashes in the area for a couple of reasons. First, freight traffic in that region is high — trucks make up a larger percentage of the cars on the road in that stretch of Metro Atlanta than many others. And trucks are harder to maneuver than smaller vehicles, meaning a loss of traction can displace a lot of weight and cause calamitous results. Big rigs also have to navigate bad drivers in cars, and trying to stop a big rig on a dime is a lot harder than woahing down a smaller ride. This is true on any road, but proven true often in the I-75/I-675 interchange.

The Georgia Department of Transportation has noticed the same trend and is working on solutions both long and short term.

“This interchange certainly has our attention. The vast majority of incidents at this location occur during inclement weather when drivers are not driving appropriately for conditions or at proper speeds for conditions,” GDOT’s Natalie Dale told the AJC and WSB.

At the beginning of this month, the state says they installed signs on both sides of I-75 in that area. The signs warn of the dangerous curve ahead and advise drivers to travel at 55 mph. The signs also warn motorists the area is slippery when wet, something too many have learned the hard way.

GDOT also is working with smart transportation system Drivewyze. Drivewyze is normally deployed in trucks to help them avoid stopping at weigh stations. But their in-cab notification systems can also send messaging to drivers, similar to how a GPS would. GDOT is soon installing a beacon on I-75/southbound just before the I-675 merge that will alert Drivewyze users of the sharp curve ahead. GDOT hopes to have this in use within a month.

Extra signage has been a big difference maker in one previously perilous Metro Atlanta junction. The I-285/southbound ramp to I-20/eastbound (Exit 46) in DeKalb County used to see nearly weekly instances of tractor trailers turning over. But GDOT added copious signs every few feet to warn drivers, especially those from out of town, of the sharp curve and the suggested speed. Now big-rig crashes rarely happen on that ramp.

The I-285/I-20 interchange in DeKalb is due for a redesign in a few years, but the state did not wait until then to address a big problem. The signs worked. And after the signs and the smart alert beacon, there could be bigger design plans for the I-75/I-675 interchange in Henry County.

“Our engineers are currently studying the interchange, and they have some proposed designs they’re working on,” Dale said. “We had already scheduled a project to repair and replace concrete slabs that would enhance friction for drivers. In addition, due to the age of the road, our engineers have been studying the area to encompass some ‘reshaping’ of the roadway and are actively pursuing a project that combines both solutions.”

So help is on the way. But one thing everyone can do, in chassis big and small, is slow down and remember that crashes happen quite often in the rain at I-75 and I-675. That awareness alone can certainly save some delays and pains.

Doug Turnbull, the PM drive Skycopter anchor for Triple Team Traffic on 95.5 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@cmg.com.