Gridlock Guy: A refresher on the jams that lane shifts cause

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The Atlanta road system is in construction parallax; it has to be. Our population continues to grow and the externalities of this expansion manifest themselves in the way of trucks, cones, barrels, bulldozers, barriers, and paint. The most ostensible and cumbersome of these projects is the immense Transform 285/400 project in Sandy Springs. That interchange redesign came on the heels of the massive I-75/I-575 Northwest Metro Express Lanes construction in Cobb and Cherokee counties, which concluded last September.

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Even small road adjustments and improvements can cause closures, but more subtle construction changes can cause intense delays without actually blocking lanes. One such side effect of big-time road work is a lane shift or lane restriping.

An avid WSB listener who wishes to be called “Traffic Trooper Squirrel” (they love squirrels, in case you’re wondering) asked me a great question, as they approached one of these work zones on I-75 in Butts County: What is a lane shift? Squirrel is from another country and isn’t familiar with certain American vernacular.

That question put the presence of these slants in travel lanes front and top of mind for me. When construction crews have to build bridges or build out lanes next to roads, they often have to take some capacity from the regular through lanes. Instead of blocking an entire lane for weeks and months, they restripe the lanes. Usually, crews will paint the lanes with a slant to the left or right, and sometimes they make the lanes skinnier, to allow for this construction. This causes problems.

Any time the environment changes, traffic cringes. When just a bit of rain falls, people make wrecking look easy and traffic automatically moves more slowly. So certainly when travel lanes suddenly juke left or right and constrict, the travel flow slows. And this ripple in the “trip time continuum” causes more wrecks as well, which then cause even more delays.

Take the pain that Cobb commuters felt on I-75 for the several years leading up to the completion of those new toll lanes. The lane shifts between I-285 and Marietta slowed traffic at very unpredictable times of day. And this happened simply because a few more variables (lane shifts and restriping) joined the commuting equation on that stretch.

In recent weeks, the I-285/westbound ramp to Peachtree Dunwoody Road and exit lanes to GA-400 have been restriped. Crews there did eliminate a net lane of capacity, taking the left exit lane to Peachtree Dunwoody and making it an exit lane to GA-400. That has made the exit to “Pill Hill” a nightmare, which backs up the right lanes of I-285 even worse during both rush hours. Add in the lane shift on I-285 in that same area and lane shifts on GA-400 in that spot and “slower than normal” has become the new normal.

The new Peach Pass lanes on I-75 and I-575 have brought plenty of relief to the northwestern suburbs. I-75 used to be awful, but has instead moderated greatly with the addition of the two reversible lanes during each rush hour. However, a new lane shift just last week on I-75/northbound north of Chastain Road, combined with construction equipment sitting off to the right, has done to Marietta-Kennesaw traffic what a pugilist did to Jared Leto’s beautiful face in “Fight Club.”

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The new I-75/northbound lane shift north of Chastain Road has made the Cobb County commute a lot worse. Credit: Doug Turnbull, WSB Skycopter.

The new I-75/northbound lane shift north of Chastain Road has made the Cobb County commute a lot worse. Credit: Doug Turnbull, WSB Skycopter.

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The new I-75/northbound lane shift north of Chastain Road has made the Cobb County commute a lot worse. Credit: Doug Turnbull, WSB Skycopter.

The lane shift and restriping on I-75/northbound in Kennesaw has turned what had decreased to a sub-20 minute ride from I-285 to Chastain into a 30-minute-plus trek. No lanes are blocked; conditions simply changed.

There are many more examples of what restriping, lane shifts, and lane constriction can do to traffic. But there aren’t really many great solutions on how to minimize their impact. As motorists, we need to drive with more awareness and with more authority. We can still be cautious and decisive; those are not mutually exclusive traits. And let this serve as a reminder to always drive at our best in work zones, because mistakes in these areas are more costly. Construction areas often leave less room for drivers to correct themselves or pull to a shoulder, and crashes and inattentiveness have higher chances here to cost lives. Construction is with us for years to come — please be careful.

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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 Contact him at