Reflective lane lines?

[N8N]

I remember a few, probably 5+ years ago, reading that there was a shortage of one of the materials used to make painted lane lines reflective. Well, last night was one of those nights in the DC/Baltimore area where such would be helpful - it's obviously late November, so people are commuting home after dark, and it'd been raining fairly heavily since at least mid morning, to the point where there wasn't really standing water on the roads, but that thin layer that makes it just a little shiny. Well, even though I was driving my E92 335i which has what seem to be fairly decent headlamps out of the box, the only roads on which I could easily see the lanes were those that had little reflectors actually embedded in the asphalt. I and clearly many other drivers were clearly struggling to see the painted lane lines and in some cases they actually appeared shiny black, not yellow or white.

Is there still a shortage, or is this just a sign that the lane markings haven't been renewed in far too long?

 

[alpg88]

yea, shortage, but not of paint, city officials chose to spend money somewhere else.

 

[N8N]

yea, shortage, but not of paint, city officials chose to spend money somewhere else.

and the State of Maryland and other various agencies... (I-295, for example, was no better than any other road)

 

[bykfixer]

There are 3 types of lines.
1) Paint. It's 19 mils thick so the reflective glass beads that are about 8 mils thick don't last very long. It costs DOT's about 10 cents a foot to apply. When there are tens of millions of feet to restripe annualy the dollars go a long way.

2) Thermo-Plastic. It's about 90 mils thick. The same glass beads are used and the reflectivity along with the color lasts a lot longer. It costs between $1.50 and $5.00 a foot depending. It's usually used on new pavements. It stays brighter in places that snow plow blades don't scrape off the reflective beads each winter.

3) Reflective Tape. That is used on interstates and is quite expensive. It lasts about 10 years even after snow because it is textured. Snow plows don't scrape off the reflective particles in the pores.

Those reflectors cost between $5 and $25 each depending. But they last a good long time.

One thing as a road inspector we insist on is joints in the asphalt to match the lanes. That way when the striping gets dull a driver can use the pavement joints as a guide in the rain or when the pavement is wet. Sometimes even in daylight a wet pavement can cause stripes to be difficult to see.

The town I live in hired a contractor (when I worked there 25 years ago) to restripe all main roads with thermo plastic. That stuff doesn't stick to paint so the paint had to be scraped off first then the molten plastic applied over the roughened surface. It costed a million dollars but it lasted about 20 years. That was about 800 lanes miles. A lane mile is a mile for each lane.
Example: A 5 mile, 4 lane road would be 20 lanes miles.

Edit: adressing the material shortage;
The reflective material in paint and thermo-plastic is tiny round glass spheres. There's typically plenty of those. Same with the paint and plastic.

It's the yellow dye that is short supply at times. There's a specific shade of yellow required. Mustard yellow is too dark. Lemon yellow is too light.

Now, getting the right shade isn't the hard part. It's developing a shade that does not darken or fade over time that is the hard part. The Federal Highway Administration (FHWA) test the dye being produced enmasse and at times reject a batch for one reason or another. It takes time and testing to develop another batch. A batch can be millions and millions of pounds of yellow powder. So there are times of shortage of yellow dye.

At times the tape is in short supply also. The last two years (post Covid) all that federal money for "shovel ready projects" had led to massive repaving projects across America. At times the tape manufacturers could not keep up with demand. Other times suppliers were selling it faster than they could resupply. Unintended consequences of economic stimulous packages.