Low overpasses are an RVer’s nemesis. It’s not uncommon for trips to be disrupted and detoured due to low clearance structures. If your travels lead you to Durham, NC, be very aware of the Norfolk-Gregson St. Overpass, known simply as the 11-foot eight bridge.
This overpass has gained notoriety for being the fate of roofs of trucks, moving vans, and RVs due to its devastating low clearance. Take a close look at this video for a firsthand account of what happens to over-height RVs traveling under this bridge:
Located at the intersection of S. Gregson St. and W. Peabody St. in a popular area of Durham, the overpass has been dubbed the “Gregson Street Guillotine” and the “Can Opener Bridge” by the media and the general public. In fact, at one time the low clearance bridge would cause at least one overpass accident a month for over-height vehicles.
While clear signage surrounding the bridge has been installed throughout the years to ensure driver safety, incidents keep occurring. General causes? Drivers who would ignore the clearance signage located on both sides of the road, the flashing warning lights overhead, and/or quite simply, the entire overpass itself (until it would be too late).
“We are having a hard time figuring out exactly why this is happening,” says John Sandor, Deputy Division Traffic Engineer for the North Carolina Department of Transportation – Division Five. “It’s kind of a phenomenon and it seems to just creep up on folks who don’t yield to the signs. The overpass was built in the 1900s when vehicles were not as tall as they are today. But it has had appropriate signage and it was over signed if anything. Still, these types of crashes have taken place.”

A truck getting stuck under the overpass. Photo courtesy www.11foot8.com
The bridge is owned by the North Carolina Railroad and while construction efforts have been considered to raise the bridge or lower the road, it’s not as easy as it sounds. For example, to make it higher would mean having to raise railroad crossings overhead, while making the road lower is not an option as major sewer lines lay a mere four feet under Gregson St.
“If this was an easy thing to address, it would have been done by now,” says Sandor. “It would be a very significant construction project and very costly to complete. There’s also a train station down the road so that would be a whole other world of changing things. That leaves to lowering the road, but it’s already in a low spot in town so there are drainage issues.”
Ten years ago there was an increase in impacts. There was a warning sign installed with a height detector that would trigger flashers to go off, and warn drivers of too low of a clearance. That had some impact but we have seen the problem come back over the last five years. We felt the need to take another step to see what else can be done. That’s where we are today.

A new traffic signal was recently put in place right before the overpass. This automatically indicates over-height vehicles that will not make it under the bridge. Photos courtesy www.11foot8.com
Take measures against this overpass
Despite the high number of bridge collisions on Gregson St., RVers do have alternatives. For instance, GPS technology offers several features for precise navigation. RV trip planning tools such as RV LIFE Trip Wizard allow RVers to easily custom build a route to avoid low clearances, find alternate roadways, with many other features to safely arrive at a destination.
As a starting point, according to Sandor, it’s recommended to stay away from U.S. 15-501 business routes in Durham to avoid any encounters with low bridges (including the Gregson St. overpass). As a further safety measure, the city recently put a new traffic signal in place right just before the overpass that automatically indicates over-height vehicles at the intersection.
“It just works out that there is a frontage road. A new system is in place that now automatically signals a turn-off point for over-height vehicles,” says Sandor. “An over-height vehicle will trigger the signal (that clearly reads “overhead vehicle detected – must turn”). The signal will hold red for what we hope will be long enough for drivers to think twice. They can then turn left or right and avoid the bridge altogether.”
The Norfolk-Gregson Street Overpass leads to a popular business area with restaurants, shopping and other attractions that can be distracting. RVers must be cautious and stay alert to prevent becoming victims.
“The new signal may not be the final cure,” says Sandor. “At least we know now that drivers with over-height vehicles are starting from the signal at 0 mph. They now have time to recognize the overpass and determine if it’s too low to drive under.”
I used to live near a bridge even lower than that, when I lived in Japan. It was on Tama-gawa, just downstream from Noborito, and a frontage road that followed the river passed beneath it. It, too, was a railroad bridge. It was eventually replaced with a taller, stronger and wider bridge. RVs are rare in Japan (I only know one Japanese who has one) and truck drivers all knew to avoid that route, so crashes of any kind were very rare. Also, most Japanese are pretty safe drivers. It’s a lot harder to get a driver’s license there than it is here.
However, once night as I was walking along the river, an SUV came along with bikes on a rooftop carrier. I looked and thought “There’s no way they can get under there; surely, they’ll stop.” Nope. Went under it at full speed for that road (probably about 30 MPH) and left the mangled bikes on the road. They stopped, then.
You can see the new bridge here, on Google Maps:
https://www.google.com/maps/place/Noborito+Station/@35.6207263,139.5705955,152a,20y,41.76t/data=!3m1!1e3!4m5!3m4!1s0x6018f1274ae97203:0x63043e008d768f4a!8m2!3d35.6207662!4d139.5700976
The bike/walking path passes very close under the bridge, on the levee top. With the old bridge, I had to duck low to walk under it. Usually, I just went down the face of the levee and walked there to get past the bridge.
I was just thinking about the Overheight sign, and two things would probably make it more effective:
1) It should flash, rather than statically display “Overheight”
2) Make it a video sign that shows the overheight vehicle, possibly with the words “Yeah, you!” included 🙂
I’very seen many YouTube videos of this particular overpass. There’s one in Albany on route 9, it’s 10ft 4 inches, almost ran my 12 ft 3 inches tall 5th wheel under that overpass. Saw the sign and came to a screeching halt. When you have a vehicle that high and long, you need to be a ” TRUCKER” , and drive like one.
NEVER EVER trust signs. As roads get resurfaced that posted dimension can change by as much as 8″….. Signs don’t always get updated right away and phone apps are even slower. Maps don’t change until the next printing. If you feel you are that close, have a spotter of find an alternative route !!!.
And surely fixing a problem like this would usually be trivial: simply dig out a few more feet of dirt from the road under the bridge and resurface. One can only conclude: THEY DON’T CARE.
Rodney, did you read the article? It’s a low area with bad drainage and it has sewer lines only 4 feet below the current road level.
I see so many people saying they use GPS or Map Books to advise them of low overpasses/bridges. BAD move !! As roads get resurfaced the clearance can change as much as 8″ or more. Signage is not always updated right away and GPS is even slower. Map Books don’t update until the next printing and even then not always correctly. If your that close have a spotter or find a different route.
On this same thought……. I friend of mine was in Las Vegas just last week. Prior to his trip he added airbags and upgraded tires on his stock height truck. As he pulled into the SAMN gas station he had been to several times he took the AC off the top of his trailer !!! Again, he had been there SEVERAL times in the past. The airbags and new tires were just enough to raise his truck up enough to catch the station canopy.
If you don’t know the height of your rig, stay off the road. You’re too dumb for your own good.
Oops! This is EXACTLY why people must know their vehicle height and post it on a label on their dashboard.and check the clearance on overpasses bet sometimes that isn’t enough.. When I was a long-haul semi driver in 1959 and driving through New York I took off two inches off my trailer roof four feet back on an overpass. My trailer was 11′ 10.5″ and the clearance of the overpass was marked !2′ 2″ which would indicate that I would clear it Little did I know that the state regraded the road over the old surface three days previous to the incident and they failed to update the clearance signage. I filed an accident report at the scene with the NY State police and notified the state that I would be sending them a bill for the trailer repair.and they said they weren’t responsible in a letter I received at my office in Sparks, NV. I responded wit a letter to them that I would be suing them and would be asking the court for the cost of the trailer repair, the cost of lost revenue, my attorney fees and multiple costs of airline trips between Nevada and New York for me and my attorney to attend court: $15,000 for my attorney’s room and board when not in Nevada, and $10,000 for my room and board when not in Nevada for each trip we had to make to New York. In addition I would be asking the court for $5,000 each for our time for each trip. Needless to say they called me and informed me that they decided to pay the $8,200 bill that I submitted to them for the trailer repair. They told me the check would be in the mail the next day or two days at the latest. I told them I wanted the money the next day or I would be filing the suit tomorrow at noon because I had to pay for the repair out of my pocket. They asked me for my bank information and they would make an electronic transfer immediately. I gave it to them and I had the money within 1 1/2 hours. I had reported it to my insurance company and told them to hold off until after I tried to recover the money from the state. They were very happy that they were off the hook for the money. Mess with the bull and you get the horn..
“This is EXACTLY why people must know their vehicle height and post it on a label on their dashboard.”
In both English and Metric units.
A couple summers ago when getting back into RVing after a very long absence (grew up with trailers and motorhomes, but hadn’t owned one of my own), my first step was to rent a large bunkhouse model class C from El Monte for a family vacation. That rental had a clearance sticker prominently displayed in the cab, which said the height of the vehicle was 13 feet. I never questioned the veracity of that claim, until one day of our trip.
We were going up the road to toward the Bryce Canyon area, and came to one of those short tunnels bored or blasted through the rock. The clearance sign read something like 11’6″. I pulled over into a large turnout right in front of the tunnel and stopped. Got out. Quietly cussed to myself. Looked at the tunnel and looked at the motorhome. Thought, “That sure looks like it will fit.” Walked over to the (very short) tunnel, waited until no cars were coming, then walked through it and back. Looked at everything. Moved the motorhome up to the end of the turnout nearest the tunnel.
Eyeballed the motorhome and the tunnel some more. Thought to myself that if this tunnel is 11-6, there’s no way that motorhome is anywhere near 13 feet tall, and the tunnel sure looks like it’s more than that in the middle; the 11-6 is probably where it starts to curve down at the sides. I polled my wife and my dad for their opinions while the kids were playing by the stream. They concurred that the tunnel looked a lot smaller than the motorhome. We all decided to do it. My dad walked to the far side of the tunnel to act as a ground guide. The rest of us got in.
I waited until there was no traffic coming in either direction, pulled out into the middle of the two-lane highway, and slowly drove through the tunnel, straddling the center line, while my dad watched from the front, ready to give a stop signal if it looked like we were wrong. Passed through the tunnel without incident, pulled over, dad got in, continued up to Bryce and arrived at our RV park without incident.
After I got home, I did what I should have done before we left, rather than believe the sticker, and measured the height of the vehicle, from the top of the A/C unit to the ground. It was right around 10 feet. I don’t blame El Monte for putting a sticker in there that says 13 feet; I’d probably do the same thing, if I were renting out my vehicle, since there are too many people out there who will try to drive under anything. Telling them the vehicle is three feet taller than it really is, well, that’s just a good defensive measure 🙂
The class A I now own is 12’4″ to the top of the A/C units. I suspect the centerline clearance of that tunnel is about 13 feet, but I don’t think I’d want to test that assumption with a vehicle this tall, even driving down the center of the road 🙂 Even at the corners, my MH is 11 feet, so that’d be a pretty close shave in that tunnel. Without a way to measure the tunnel before proceeding, I’d have to find another route into Bryce.
Not an engineer however, why can’t the structure of the bridge be changed to suspension or mechanical raised perhaps and find the 6″‘s they need to stop the collisions? A combination of digging down a few inches before running into the utilities as well as using a different bridge structure could be a multi faceted fix to this bridge dilemma.
I’m an RV owner as well as a truck driver, so in no way am I suggesting that folks shouldn’t be aware of the height of their vehicle. But….why don’t they hang that “over height must turn” sign on chains so drivers will hit the sign (and hopefully stop) before they hit the bridge. What I really picture is a thick, heavy, yellow or orange, indestructible mud flap bolted or hinged directly to the pole between the 2 traffic lights. Something that wouldn’t snag when the driver realizes their mistake and has to back up. That would make it cheap and nearly maintenance-free for the city or railroad.
As a truck driver for 20+ years, I’ve seen my fair share of low clearance situations. Some surprises and some close calls. The technology has come a long way with low tire pressure monitors, vehicle presence detection and accident avoidance warnings. I guess these types of accidents are so rare, no one has seen a need to develop something to detect a low clearance with enough time to autonomously stop a heavy RV or tractor trailer. At least, not that I’m aware of. Of course, there are GPS systems that warn drivers and reroute orver height vehicles, but no one should rely on it 100%. It should definitely be built in to an avoidance system, though. Such a system will need as much early warning as possible to alert the driver and take action, if necessary. I’m sure someone’s working on it somewhere.
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Non-destructive warning barriers are pretty common, but are not always practical to install… and many truckers have slammed into bridges despite them.
I assume that there are multiple brands, but the Giraffe G4 (http://giraffeg4.com/) is one example of an available system for trucks and RVs. It only warns – doesn’t apply the brakes – but I wouldn’t want this sort of system slamming my brakes on anyway.
In addition, some navigation systems compare clearance data from the map database to the user’s entered vehicle height and alarm if the path is about to go through a place with inadequate clearance. The effectiveness of this is limited by database completeness and accuracy, as well as GPS performance.
I wonder if the driver knew that his RV height was 11′ but it didn’t include the AC and other rooftop additions. I know the height of my RV as listed in the brochure but never thought about if it includes these things.
How stupid are these drivers not to see warning lights and signs. If they still drive into the low overhead they deserve what they get. What a bunch of dopes…