If you’ve ever driven on a road without street lighting or on a slippery road, you’ve probably realized the importance of clear road markings. Fresh white lines are easy to spot, but old, faded lines will make your eyes strain to keep track of the direction, making even a simple drive a tedious task. But what if there was a better solution? What if the markings could light up automatically?
The Australian state of New South Wales is currently testing illuminated road markings. The aim is to improve visibility beyond the normal lanes, which will ideally help drivers navigate the road better. The illuminated lane markings also suggest that a long-standing problem – road markings disappearing in the rain – can be solved.
This may seem like an obvious idea, but it begs the question: why hasn’t nighttime lighting become the norm? To understand why, we need to look at how lane markings work, why they sometimes disappear, and the history of illuminated road markings.
This is what the first Kudara test site looks like when transitioning from day to night.
There is a common hazard that many young drivers face. On my first drive in the rain on a busy highway, the lane markings suddenly disappeared, melting into the asphalt, and at night the situation became even worse. It is a common problem, but one that has proven very difficult to solve.
Usually, lane markings are clearly visible even when driving at night. This is because the road marking paint has tiny reflective glass beads embedded in it. These glass beads are designed to reflect headlights back into your car so that you can easily see the lane markings in the dark.
However, when the marker gets soaked in water, the water messes everything up. The water changes the path of the light so that it can no longer be reflected back. This makes the markings hard to see.
It would seem like an obvious solution to make lane markings illuminate automatically. Instead of reflecting light, they emit their own light in all directions, making them more visible in a wider range of conditions. Simple, right? Plus, it can also improve visibility at night.
It turns out that illuminated lane markings are not science fiction. At least in Australia, they are now a reality. Whether they will become widespread, however, is another matter entirely.
In December last year, the New South Wales government announced a trial of new road markings on a mountain road south of Sydney. The project, called Glowing Roads, will test the use of photoluminescent road markings that absorb sunlight during the day and glow at night. In short, it’s road markings that glow in the dark. On rural roads where street lighting isn’t possible, the program aims to make illuminated lane markings more visible to drivers.
The first area to be treated is a complex hairpin bend. In the darkest hours of the day between 9pm and 4am, the site saw 125 near misses. The light markings in this area are designed to make sharp bends more visible at night, giving drivers the best chance of negotiating them safely. “Being able to see the shape of the road ahead is critical to safe driving and that’s what ‘easy roads’ are all about,” said NSW Roads Minister John Graham.
“The data shows that around a third of fatalities in New South Wales occur at night,” Graham said. “If this trial is found to be successful, we will consider applying it to other locations where there have been crashes or hazardous situations where better visibility is required.”
NSW Transport Minister Josh Murray said: “Glowing Roads was the brainchild of our Department of Transport Transformation team, who were looking for a solution to improve safety in remote or isolated areas and came up with the idea during an internal innovation competition. Before Glowing Roads was officially launched on public roads, we tested the new markings and glowing paint in a range of conditions at the Future Mobility Proving Ground to ensure they were ready for the next stage of testing.”
It is hoped that these glowing lines will be particularly useful in conditions of extremely poor visibility.
NSW Minister for Regional Transport and Roads Jenny Acheson said: “Residents know that visibility on this road and others like it across the state can be dramatically reduced in seconds when fog or storms hit. I look forward to seeing how this innovative technology performs in these conditions.”
It is clear that New South Wales residents are enthusiastic about the project. Drivers and officials will be watching closely to see if the project delivers on its promise of improved visibility and safety.
The idea of illuminated road markings is so intuitive that one might wonder why no one has tried it before. In fact, several jurisdictions have experimented with the concept over the years. However, until now, illuminated lane markings have not gained widespread acceptance.
In fact, the Australian state of Victoria conducted such an experiment in 2022. The media rushed to publish the story and were excited about the new hot topic. But few paid attention to the subsequent developments of this research. I contacted the Department of Transport and Planning to find out what was going on, but was disappointed. According to the department itself, the technology is not considered a significant safety improvement:
The Department for Transport and Planning has trialled photoluminescent markings on five rural roads as part of a road safety project.
Following the tests, the researchers conducted an independent assessment of the technology’s road safety benefits. It should be noted that the assessment results do not include extremely low-speed conditions, such as sharp turns on motorways.
The review concluded that the road safety benefits are not sufficient to justify the installation of photoluminescent markings on more roads. However, in situations where headlights or street lighting are not available, such as on public roads, the use of photoluminescent markings may provide greater benefits.
A thermoplastic luminescent coating applied over existing road markings has been tested in Victoria. Fabulous!
The trials were eventually stopped without further deployment after an independent investigation found the technology “did not provide sufficient road safety benefits.”
Other countries have come to similar conclusions. According to the BBC, the Netherlands was one of the first countries to take part. In 2014, authorities tested the light treatment on a section of the N329 motorway and had high hopes for its effectiveness. The aim is for these special glow-in-the-dark threads to be charged by sunlight during the day and continue to glow for eight hours at night – longer than traditional glow-in-the-dark coatings. It is hoped that in some cases they could even become a viable alternative to street lighting, thereby saving energy.
However, after just a few weeks, it became clear that the paint did not hold up well to heavy rain. Moisture corroded the light markings, significantly reducing the light output. In these conditions, where they could be most useful, they were completely ineffective. Drivers even deliberately turned off their headlights, trying to feel the effect of night lighting, which suggests that with the headlights on, the light effect was not that useful. There were hopes for version 2.0 of the light strip markings, but they were never realized.
In 2017, Shell released a beautiful video of illuminated traffic lanes in the Netherlands, three years after the technology was found to be flawed.
Malaysia also experimented in this direction in 2023. More than 1,600 feet of road markings were applied at the intersection of the B19 and B16 highways. The paint used can emit light for more than 10 hours and helps improve visibility on rainy days.
Unfortunately, it turned out that the paint was 19 times more expensive than regular road marking paint and not as effective. Reports from the field showed that the glowing paint was losing its properties or wearing off within just a few weeks. Ultimately, the government decided not to install glowing stripes on other roads.
It is worth noting that regular white lane markings work very well if they are properly maintained. The vast majority of lane markings use glass beads, which give them reflective properties, so that they reflect the light from the car’s headlights directly back to the driver. This technology works well – the car provides enough light, and the marking lines are usually clearly visible. The main problem is that these markings can fade or age, and the glass beads can become damaged over time. However, this is a maintenance issue, and road marking illumination does not really solve it.
The downside to illuminated road markings is that they emit very dim light. Most cars, especially those with modern headlights, emit a lot of light onto the road ahead. The extra light from the luminous coating doesn’t necessarily make a big difference. Think about it – if you’ve ever put up glow-in-the-dark stickers, do you remember having to be in a nearly dark room to see them?
In the years since the Dutch project, the prospect of illuminated lanes remains promising. As we mentioned above, rain is known to limit the reflectivity of traditional reflective markings. The hope is that illuminated markings will be more visible in such conditions because they emit light rather than simply reflect it. An example is the Utah Department of Transportation (UDOT).
Since 2020, UDOT has conducted a series of limited studies on luminescent road paints. The agency has collaborated with the University of Utah to develop solutions to problems raised in the previous Dutch lawsuit.
The researchers were aware of a study in the Netherlands that found that rainwater leached key rare earth elements that give paint its glowing appearance. The research led to a special polymer coating for light-emitting ceramic phosphors designed to prevent degradation from moisture. However, this is not enough to ensure widespread adoption of the technology. Despite the enthusiasm, Utah still does not have a network of glowing neon roads. Instead, the Utah Department of Transportation has focused on applying contrasting black and white lines to improve visibility in rainy weather, rather than relying on glowing coatings. They have also figured out a way to extend the life of the reflective coating. When applied to the road markings, reflective glass beads are embedded deep enough into the grooves of the road surface to protect them from damage from the blades of winter snowplows.
Illuminated lane markings have been extensively researched and field tested around the world. Authorities hope that they will be able to better display road outlines in dark areas or make road markings clearer in fog, rain and wet conditions. However, despite these efforts, no transport agency has ever used illuminated road markings on a large scale.
It seems to be both a performance and durability issue. Illuminated lane markings are not very effective and have a short lifespan. There are no significant studies showing that illuminated lane markings significantly improve visibility or reduce accidents. While they look cool, the DOT is focused on science, not aesthetics. Without supporting data, deployment will not happen. Additionally, most trials suffer from the problem of rapid degradation of illuminated lane marking paint. The last thing the DOT needs is new lane marking materials that require frequent replacement and are more expensive.
What’s happening in New South Wales could be possible because the state is trialling a very specific technology. Specifically, they want to use illuminated road markings on sharp bends to attract drivers’ attention and prevent them from drifting off the road. While illuminated road markings don’t seem like a real improvement for regular roads or motorways, they could be useful on dark roads and on sharp, low-speed bends. In these areas, runoff from roads is common and can have dangerous consequences. However, to justify the promotion of illuminated road markings, they still need to outperform traditional solutions such as signs and road reflectors.
For illuminated road markings to be truly effective, they need to be brighter and more durable. However, at the moment, it is unlikely that we will make significant progress in this area unless we discover some new phosphorescent materials. Perhaps one day we will see LEDs or other light-emitting technologies illuminating roads. However, when it comes to bright light, it seems that technology is not up to the task yet.
The bottom line is that unless you’re in New South Wales, don’t expect to see illuminated lane markings anytime soon. So far, their only usefulness has been as a great photo opportunity for the transportation department. They look great, but after a decade of experimentation, they’re still a novelty. It’s a shame these fancy glowing roads don’t provide more value, but for now, they’re just reality. Meanwhile, UDOT’s efforts to improve visibility on wet roads are relatively simple and easy to implement, and if they prove effective, they’ll likely be replicated.
Lane markings are an esoteric art that you may never have thought about. However, it takes a lot of thought and engineering to make road markings as safe and visible as possible. Numerous studies have confirmed that these bright, light-emitting technologies may not be of much value, but that doesn’t mean there isn’t room for improvement.
Image credits: Transport for NSW, Transport of Victoria, Minister for Labour Alexander Nanta Linggi via Facebook, UDOT, Shell via YouTube Screenshot
Usually, lane markings are clearly visible even when driving at night. This is because the road marking paint has tiny reflective glass beads embedded in it. These glass beads are designed to reflect headlights back into your car so that you can easily see the lane markings in the dark.
Unless you live in Michigan, where plants don’t reflect light at all and may even absorb it.
The problem with reflective paint is that it relies on the difference in refractive index between glass and air, so you can’t put it in water. Glass beads are pretty cheap, so coming up with a cheaper paint was a bit of a challenge.
Post time: Apr-17-2025