Drivers are perplexed, even terrified, by what they see on Colorado highways. Or, more specifically, what they don’t see.

The highway markers that are supposed to keep drivers in their lanes are faded and pale on the best of days, say motorists.

By the time ice and snow arrive, those same markings are usually obliterated.

“It’s just scary,” Castle Rock commuter Susanne Krum said. “At nighttime, it’s incredibly dangerous coming down I-25. The concrete barriers are the same color as the road and the snow. I don’t know why people aren’t continually driving into things around here.”

Lane and shoulder markings — worn thin by traffic, scalding sun and de-icing chemicals — seemingly disappear when winter storms roll in.

“When the wind is blowing and the snow is blowing, you could find yourself two lanes over on a lot of these roads,” said Mike Adinolfe, chairman of Direct Transport Services, which includes a fleet of 50 trucks that carry freight across the country.

Colorado is one of the worst states, by far, when it comes to highway markings, Adinolfe said.

“You can see places — like Wyoming — where they’ve maintained their roads and you see the fresh paint,” he said. “It makes all the difference in the world.”

On rural Wyoming roads, crews repaint in the spring and make another sweep in the fall.

“We want to make sure the roads are nice and bright by the winter,” Wyoming Department of Transportation district traffic engineer Randy Griesbach said.

The Colorado Department of Transportation tries to keep up, spending $20 million each year to apply reflective water- or epoxy-based paint, thermoplastic material and tape to nearly 9,000 lane-miles in the state.

Most roads get the epoxy-based paint. To keep the markings shiny and visible to motorists, glass beads are either dropped or sprayed on immediately after the paint is applied.

State and local crews all follow Federal Highway Administration standards for markings. They also work almost continuously restriping faded markers, officials say.

Still, the volume of traffic each highway and byway attracts — from Santa Fe Drive to Titan Road, on Interstate 225 through Aurora, along I-25 between Colorado Springs and Castle Rock — influences what material is used to keep the lane markings clear, traffic managers say.

The epoxy-based paint usually lasts at least a year, sometimes three, but it will fade more quickly in areas where traffic is heavy. Magnesium chloride, which Colorado uses to de-ice roadways, also takes a toll on reflective material. Plus, motorists often complain that newly applied mag chloride can cause a harsh reflection if the sun is out.

“It all depends on the wear,” said CDOT traffic engineer Shane Chevalier. “I-70 West is a different animal than I-70 East. You have different traffic volumes and snow removal. All those factors weigh in a material’s durability.”

Colorado’s sun and high elevation take the greatest toll on highway markers, Chevalier said.

“We get 300 days of sunshine, and we are 5,000 feet in elevation,” he said. “That can quickly degrade a product that usually lasts up to five years.

“After all, what happens to your car if you leave it out in the sun without applying something on it just about all the time? It loses most of its luster in a short amount of time.”

Many local streets in Denver are not striped. But major arterial streets — such as Broadway, Speer Boulevard and Colfax Avenue — get markings, as do collector streets such as Logan and Grant, said Denver Public Works Department spokeswoman Emily Williams.

Plastic markings are the most durable, by far, and are used on newer roads and recently repaved ones, Williams said.

Plastic is also the most expensive material to use — running 60 cents to $3 per linear foot. Paint goes for 18 cents per linear foot.

Reflective raised markers, sometimes called cat’s eyes, are not typically used in Colorado because they can damage snowplows when run over by the blades.

“We have to make sure plows have a good clearance,” Williams said. “If it hits something with its blade, something bounces back up, and that is not good.”

Critics counter that cat’s eyes — used heavily in the United Kingdom — can be mounted on a durable white rubber housing that sinks when a car or plow drives over it.

Traffic managers say they are always looking for new reflective materials that are durable and cost-effective. Some motorists say Colorado road managers should look to California, which they say is the gold standard when it comes to road markings.

California uses Botts’ dots to mark lanes on most freeways. These are low, rounded white dots used in conjunction with raised reflective markers to indicate traffic lanes.

Indeed, motorists posted on Facebook several ideas to improve Colorado markings, including using blue paint or reflective bumps.

Or a sensor could pop up from the pavement after detecting a drop in temperature, to warn motorists that bad weather is approaching, suggested Denver’s Joshua Sandoval.

“I mean, we have a lot of smart people living here,” he said. “Surely, there is somebody out there with a better way of lighting up our roads.”

Monte Whaley: 720-929-0907, mwhaley@denverpost.com or twitter.com/montewhaley

Numbers

9,000

Lane-miles of highway for which the Colorado Department of Transportation is responsible

$20 million

Annual cost to maintain lane markers

$3

Upper end of the cost range, per linear foot, of plastic-line lane markers