Moving speed limits on I-285

Moderated by Tom Sabulis

On Sunday, north side motorists will discover a higher base speed limit and new variable speed limits on 36 miles of I-285 north of its two interchanges with I-20. The Georgia Department of Transportation says the modifications will help moderate driving speeds in times of tie-ups — slowing everyone down to (hopefully) speed up traffic flow. In our second column, I talk with a Fayette County official about his county’s plans to help test driverless vehicles, a new technology being studied by a state House committee.

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Adjusting speeds on top end Perimeter

By Russell McMurry

An important new safety enhancement is scheduled to begin operating on the top half of I-285 this weekend.

Variable Speed Limits, or VSL, are to be activated Sunday on 36 miles of I-285 north of its two interchanges with I-20. The first thing motorists will see is that the base speed limit is increased to 65 mph, as it was last year on I-285 below I-20. The higher limit has worked well on the south side, and we believe it will do likewise on the upper end.

The roadway has as many as seven — and no fewer than four — lanes in each direction and can easily accommodate 65 mph travel during non-congested times. While it may seem hard to believe if you’ve been snarled in one of the Top End’s epic traffic jams, for most of the day, traffic there is free flowing; consequently, we expect the speed limit to remain predominantly static at 65 mph.

The top half of I-285 does have important differences from south side I-285. The top side carries an average of 50,000 more vehicles a day – 100,000 more in certain locations — and there are nearly twice as many interchanges. More traffic and more interchanges equate to more merging and weaving movements, more congestion and, regrettably, more crashes — all of which cause backups.

VSL offers us a tool to enhance motorists’ safety by warning them well in advance of trouble ahead while simultaneously reducing the speed limit. Our Transportation Management Center operators, who monitor the top end using real-time closed-circuit cameras, now have a new tool — reducing the speed limit in advance of jammed traffic — when responding to incidents with H.E.R.O. units and emergency responders.

Overhead message boards in advance of an incident location will advise approaching drivers. Traffic Management operators will be able to reduce the approaching speed limit in 10 mph increments, to 55, 45 and a minimum of 35 mph if necessary. Being aware of slowed traffic ahead and being able to slow down accordingly is infinitely safer than unexpectedly having to slam on the brakes. In fact, secondary crashes due to backups are a common occurrence and further exacerbate congestion.

There is another benefit to be derived from VSL: “Slowing down to get there faster,” as the late WSB traffic reporter Herb Emory, our much-missed friend, would have said. Studies have shown that at slower speeds, traffic flows in a more consistent, steady manner, and motorists can arrive at their destinations quicker than via the “speed-up, stop” accordion-like movements so often seen on our freeways. That slower pace also yields better gas mileage and reduces carbon emissions and is better on driver temperament.

Some wonder if VSL isn’t just a cleverly phrased way of saying speed trap. No, it is not. It is neither GDOT’s motivation nor the intention of law enforcement agencies on the top of I-285 to use VSL as a means to issue more speeding tickets. The speed limits are lowered due to traffic conditions, crashes or weather events that necessitate a reduction.

GDOT encourages drivers to heed the overhead sign information and the new digital speed limit signs on the shoulder. The real success of VSL is the compliance, so that everyone can enjoy its benefits. While we harbor no illusions that VSL will free Top End I-285 from congestion or eliminate crashes there, it most assuredly will help.

Thank you for slowing down when the speed limit is reduced, to ultimately get there safer and faster.

Russell McMurry is chief engineer at the Georgia Department of Transportation.

Fayette looking to test autonomous vehicles

By Tom Sabulis

Prior to the first hearing of the Georgia House study committee on driverless cars earlier this month, we asked Fayette County Commission Chairman Steve Brown about pitching his county as a test ground for the new technology:

What’s the status of Fayette County serving as a test ground for driverless cars in Georgia?

We’ve formally passed a resolution stating we are willing to use our local roads for the testing. We talked to the Georgia Department of Transportation, and they are supportive, but we are awaiting final confirmation from Governor Deal’s office. We want their approval to use the state routes in the county. We can allow them today to crisscross on our county roads, but they’re going to have to eventually cross a state route or get on a state route to get to the next set of county roads. So we’re trying to be a good partner. We want to work with the state on that. We’ve spoken with Georgia Tech; they’re willing to work with us, and they have an interest in the research possibilities.

Do you need legislation passed to do this?

Our understanding is you don’t have to have legislation as long as you have a driver in the vehicle. I’m closely watching the California model. Google, I think, drove almost 200,000 miles on California highways before California DOT even knew they were doing it. Essentially, their point was, the laws covered them, they didn’t need to have special laws. California has since restructured some statutes, and they have new regulations coming out; I think they’re due by January. So they’re the leader. They’ve actually had the vehicles on the roads. There’s a lot of anxiety when you have new technology and people fear change, and of course, computers do have glitches, and what’s going to happen if I’m on the road and that happens? The new Google-manufactured vehicles are lightweight, tiny two-seaters that only go 25 mph, so that are not really a safety threat.

What are you hearing from Fayette citizens about this idea?

Peachtree City was worried in terms of participating. They didn’t know if their golf cart paths would play a part in distracting the (driverless) vehicles, if the cars could determine the difference between a road and a golf cart path. A lot of the golf cart paths do intersect local roads. So I think we have to assure Peachtree City that that’s not going to be the case. But the citizens themselves are very excited about it. This is why Fayette County works so well for testing these vehicles. You have a very affluent population, a well-educated population, a strong high-tech-user population, and I think if you’ve got a county that you would consider an early adopter for this kind of technology, it would be Fayette. We kind of fit that mold.

What do you hope comes out of these legislative hearings?

As a committee, I think they need to get a grasp on where the technology is today. I’ve been studying it for five or six years. There are four levels of autonomous driving. Right now, you can buy something on a car lot today that’s very close to level three. It’ll keep you in your lane; you don’t have to steer. It will accelerate and brake automatically via advanced sensory capabilities.

My biggest fear is, let’s not do to autonomous automobiles and trucks what we did with drones, and let the technology leapfrog the regulation, and then you ground everything. We have so many companies that are likely to be key players in the drone market in Georgia, and they’re all grounded. They can’t sell any product, they can’t move any product, and it’s pathetic. And this is where we’re headed with autonomous vehicles, because the technology is going to leapfrog the regulation. But that’s where we are going if we don’t get proactive.

Fayette County has taken the innovative step of offering our county road system not only for testing the technology, but also to serve as a policy and regulatory laboratory for the Federal Highway Administration and GDOT. Local road testing is the next critical step, and using an actual road network instead of a test track will give policy makers a genuine look at how autonomous and non-autonomous vehicles will interact. We have also made it very clear that Fayette County is allowing only vehicle manufacturers and their staff to use our road system in a controlled testing environment. Ordinary citizens are not part of the vehicle testing process.

Steve Brown is chairman of the Fayette County Commission.


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