Why A Stretch of Interstate 85 is Backward in North Carolina
Why A Stretch of Interstate 85 is Backward in North Carolina
For a few miles, the lanes on the right flip over to the left and vice versa. This happens almost nowhere else in the country. Why here? We tracked down the designer a half-century later to find out.
Some people say nothing good happens after midnight. Well, those people are wrong, because here is an interesting question from Fletch Brendan Good that came in at 4:41 a.m. Eastern time:
Several people have asked me about this! And yes, it’s true: Between Lexington and Thomasville, the lanes on Interstate 85 cross over each other. Which means, for three miles, the lanes that are usually on the right are on the left, and vice versa. If you’re having a hard time envisioning this, look at this map:
Put another way: American drivers are used to driving on the right side of the highway in almost all circumstances. But for three miles in Davidson County, the northbound lanes and southbound lanes are on the opposite sides of where they normally are. It feels… weird.
Or at least, you’d think it would feel weird. Most drivers don’t notice this at all, including, initially, me. I’ve driven this stretch of I-85 maybe a dozen times, and I’d never felt anything out of the ordinary until someone pointed it out to me on a map. I’m far from the only one who’s surprised to learn about this.
There’s a reasonable explanation here: The other lanes aren’t in sight at all during this stretch. They’re hidden behind trees, and you just can’t glance over to see the cars on the wrong side of the road. The other explanation: The bridge where the lanes cross just looks like a regular old overpass. The only clue is a tiny sign on I-85 that tells you that you’re crossing … I-85.
This is strange, right? I know, I know, I’m a road nerd and I get exceedingly geeked out about things like improper highway numbering (Interstate 99! Interstate 238!) and improbably short state routes (The superfluous North Carolina Route 400, which is less than one mile in length and has no practical reason to exist) and the fact that the whole one-in-five-miles-of-Interstate-is-straight-so-planes-can-land-on-it thing is a myth. Still though, out of more than 46,000 miles of Interstate highway, only a handful have their lanes on the wrong side. So what makes this stretch so special? Why go to the trouble of building two extra bridges here? Is this North Carolina’s introduction to the opposites?
There’s a lot of informed speculation out there. But I went looking for facts.
The Interstate Flipmode Squad
First up, this isn’t the only place in North Carolina where the lanes switch sides. Interstate 77 does this for less than a mile at the interchange with Interstate 85 in Charlotte. Other interchanges in other states also flip their lanes. But in a few other places, the crossovers last much longer. Dr. Daniel Findley, an associate director with the Institute for Transportation Research and Education at NC State University, found two other stretches of Interstate highway where the lanes flip in mountainous parts of Arizona and California. In those places, the theory is that lanes were reversed because of the terrain. In general, you’d rather have a truck going up a steep or curvy road instead of down. In North Carolina, though, that doesn’t seem to be a factor: I-85 in Davidson County is relatively flat.
There are a bunch of solid theories among road nerds. Some people think it has to do with topography. Others speculated that the state wanted to build one rest area in the middle of the highway instead of one on either side. Some said it was to put in a Vietnam veterans’ memorial. And a quite a few people think the lanes flipped so the ramps to the rest area and memorial would be on the right-hand sides of the road. In a video, Findley speculates that the last reason is the most likely, but admits that he doesn’t know for sure. In fact, for all of the geeky discussion out there, nobody’s really ever come up with concrete evidence as to what the designer was thinking nearly a half century ago.
So, I tracked down the designer.
The Tim Hardaway of North Carolina Highways
First up, the building of Interstate 85 was a bit of a cluster. Parts of the highway were already built before the first “official” section opened near Charlotte in 1958. By 1965, 133 miles of it had been finished in North Carolina. But there was a gap between Lexington and Greensboro, and so the road followed a temporary route through Thomasville. After decades of delays, the last stretch of I-85 opened in February 1984, and most of the news stories expressed relief at the fact that this long overdue highway was finally finished. They also marveled at an old truss bridge from 1906 that had been moved there from Stokes County to cross a creek at the rest area.
The rest area wasn’t originally built to house a Vietnam veterans’ memorial—The idea wasn’t conceived of until 1985, and the memorial itself opened in 1991. But the rest area itself was always part of the plan. This was mentioned in a February 10, 1984 story in the Greensboro Record which also noted something odd: the opposite lanes flipped and then seemingly disappeared for a few miles. “Because of a creek, the lanes had to be spread apart in that area,” the story noted. “Rest areas also were planned for the section, so the state decided to place them inside the median to avoid having to purchase more land.” Curiously, there’s no explanation as to why the lanes had to cross over. You have to build two bridges to achieve this, and it would be cheaper to, you know, not do that.
The main source in that story was John Watkins, the division engineer for the state Department of Transportation, who noted that the design was unique. “I don’t know that I’ve seen that before in North Carolina,” he told the Record in 1984. But there doesn’t seem to be any other newspaper article that ever addressed the crossover ever again, and an online search of public records turned up nothing. Again, all of the decisions here were made at least 40-plus years ago. How can you figure out what the engineers were thinking?
Well, turns out you can just call John Watkins. “I’ve been retired 24 years,” he chuckled when I reached him by phone at his home in Greensboro. Watkins is in his 80s now, and during his nearly four decades with the DOT, he worked on any number of road projects. Still, he remembered the I-85 thing pretty quickly. “They wanted to put a rest area in the middle,” he told me. “It’s important to have an exit and entrance to the interstate from the right hand side. If you flip the lanes, you can enter the rest area from the right. That was the primary reason.” Sure, he said, you have to pay for the bridges. But you save money on rest area infrastructure, and on the cost of the extra land you’d need to build two facilities on the outside of the highway. That was one of the primary reasons why the state built a new rest area in the median of I-77, north of Statesville. That facility, which opened in 2018, cost $15 million, but state leaders said they saved $1 million because they didn’t have to buy extra land. Even so, engineers aren’t happy about the fact that you have to enter the I-77 rest area from the left lane. That’s generally considered to be more dangerous, since people are exiting and then merging into what’s considered to be the fast lane. “I would have failed a student with that design,” a retired engineering instructor told the Charlotte Observer. “To me, it’s a death trap.”
Interstate 85 and its Davidson County rest area look weird on a map, but they’re based on a better, safer design. A lot of people have asked Watkins about the reversed lanes over the years. Including, now, me. His answer is always pretty simple. “It was a design decision,” he says. Perhaps that’s the point. It’s unusual, but largely unnoticeable, because it works.