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California Drivers Are Saying Goodbye to Botts' Dots

Posted May 26, 2017 12:00 AM by Hannes
Pathfinder Tags: botts dots california driving roads

Many drivers in California are mourning their state transportation department's (Caltrans) decision to phase out Botts’ dots on the state's roads. The dots in question are round, raised pavement markers used to mark lanes on highways and arterials in lieu of striping.

Botts’ dots, which are usually comprised of either ceramic or polymer materials, were developed by a Caltrans engineer named Elbert Botts in the 1950s, and California’s state legislature mandated their use on all snowfall-free highways in 1966. (Snowplows damage or dislodge the dots, prohibiting their use in colder climates.) The markers are also used in certain western and southern states, such as Alabama, Florida, Texas, and Nevada, as well as for temporary lane marking in snowier states like Massachusetts and Pennsylvania.

There are over 20 million dots on California highways, and most drivers love them. Crossing a lane marked with Botts’ dots rather than painted stripes results in a rumbling sensation, alerting distracted drivers or awakening sleepy ones. Although a Caltrans study claims that the dots didn’t significantly affect accident rates, the internet abounds with personal anecdotes about sleepy drivers who were awakened by the rumbling on the 405 during rush hour, potentially saving their lives.

Caltrans has some pretty good reasons for phasing them out, however. First, their lifespan is shortening. The dots had about a 10 year lifespan when first introduced in the ‘60s, but traffic has increased drastically since then, so the dots take a severe pummeling that often cracks or destroys them after 6 months of use. In a worst-case scenario, a dot can break in half and fly into traffic. Another major concern is that the dots are non-reflective, so while they conveniently rumble when driven over they’re tough to see at night or when the road is wet. Some dots are installed over a reflective stripe to begin with, but they sometimes interfere with the stripe, impeding its visibility. Finally, Caltrans cites that replacing the dots—which involves walking along the lane and gluing new dots in place—is dangerous for maintenance crews.

Most interestingly, Caltrans is concerned that Botts’ dots might mess with self-driving car technology. Tests have shown that the dots can confuse autonomous vehicle navigation systems, leading to drifting and possible accidents. Personally, I wonder if the tactile feedback from the rumbling dots might benefit a drifting autonomous vehicle in some way.

As far as I know my state doesn’t use Botts’ dots, although we do have rumble strips on road shoulders. But after rush-hour commuting for a number of years I’ve seen many a driver mindlessly drift over multiple lanes. Caltrans could come up with a less burdensome solution that still involves tactile feedback, or maybe California residents will sue the state until they leave the dots in place. Either one seems plausible at the moment.

Image credit: Peter Kaminski / CC BY 2.0

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#1

Re: California Drivers Are Saying Goodbye to Botts' Dots

05/26/2017 10:06 AM

The greatest need for 'Botts dots' is along rural roads where traffic is light and there is no streetlighting. The argument that they are ruined by 'too much traffic' makes no sense in such cases. They are needed MOST where traffic is the least.

Countless numbers of times I've been thankful for Botts dots when driving at night in rural areas of Florida and Georgia. As someone who travels a lot, and also spends a lot of time in rural areas looking at the stars, driving at night on lonely roads is something I've done a lot.

I worry for my astronomy colleagues in California who will have to negotiate dangerous roads at night without Botts dots to help show the way home.

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#2
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Re: California Drivers Are Saying Goodbye to Botts' Dots

05/26/2017 1:12 PM

Around here we just figure if you can't keep your vehicle on a road in normal conditions without tactile feedback to remind you to stay in your lane you probably shouldn't be driving anyway.

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#3
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Re: California Drivers Are Saying Goodbye to Botts' Dots

05/26/2017 2:15 PM

In Wisconsin, I do like the Rumble Strips. (link courtesy of State of Washington DOT) If you do a period of driving, it does snap you out of nonthinking or intentive driving.

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#5
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Re: California Drivers Are Saying Goodbye to Botts' Dots

05/27/2017 2:56 AM

I think the NY state thruway was the first large scale application.

My state recently added a center line rumble strip on a dangerous, busy 2-lane road. Then they started taking it back out in stretches near dwellings, because of noise complaints.

Apparently, it wakes you up, even if you are not driving.

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#8
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Re: California Drivers Are Saying Goodbye to Botts' Dots

05/27/2017 10:27 AM

"looking at the stars" while driving; that's no better than texting while driving is it?

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#4

Re: California Drivers Are Saying Goodbye to Botts' Dots

05/26/2017 5:03 PM

Where this concept really shines is at night with heavy rainfall. When I was in California back in the mid-to-late eighties, there were numerous occasions I was thankful for their presence in areas without supplemental lighting.

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#6

Re: California Drivers Are Saying Goodbye to Botts' Dots

05/27/2017 9:16 AM

That reflective striping isn't all that reflective and often times can't hardly be seen, especially in the rain and fog. The reason they are only lasting six months is probably because the manufacturers are using cheaper materials to cut costs. The EPA has probably regulated the paint manufactures to the point that they can only produce inferior reflective white and yellow striping.

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Re: California Drivers Are Saying Goodbye to Botts' Dots

05/27/2017 10:20 AM

The reflective striping is usually quite worn. And at night, in the rain it's practically invincible.

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Re: California Drivers Are Saying Goodbye to Botts' Dots

05/27/2017 10:31 AM

I'm talking about new striping that dulls fast.

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Re: California Drivers Are Saying Goodbye to Botts' Dots

05/27/2017 2:38 PM

In wisconsin... I don't know if the yellow center and white shoulder lines are reflective... maybe newly applied they were. But they fade fast, eve. If the color is still there, at night, in a rain, there is so much light reflecting from the wet pavement, these lines are near invisible. At least to me they are.

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Re: California Drivers Are Saying Goodbye to Botts' Dots

06/01/2017 4:40 PM

In agricultural or construction areas, where equipment can track dirt onto paved roadways, the lines can become completely covered, even in broad day light...

At night, and/or in the rain, the ''lines'' can more easily become functionally invisible...

(Wake-up bumps) along the side of the roads can be helpfull, but are usually only installed on downhill curves. in small quantities...

(Flop-up reflective strips) are more affordable, but are unlikely to wake anybody up...

The only actually safe thing is to drive behind some body else, while maintaining more than enough stopping-sight-distance, and pull over, to let someone else lead-the-way...

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#11

Re: California Drivers Are Saying Goodbye to Botts' Dots

05/28/2017 3:37 PM

California Drivers Are Saying Goodbye to Botts' Dots, --but saying hello to illegal alien drivers.

/For shame.

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#12

Re: California Drivers Are Saying Goodbye to Botts' Dots

05/29/2017 1:57 PM

I've been in urban areas out of state where the use of reflective bumps and fresh reflective paint was such an immense sensory overload made simple exit's curves and intersections look like an intimidating Tron 2.0 environment filled with other drivers..

I remember a time in mid Florida where the roads were freshly done up with reflective everything, but the billion flashing construction lights on barrels​ that were in use at what seemed like inches away in multiple lanes made it a nerve racking drive. That and I had to dodge blue hair and Lincoln parts that was all over the road.

I also agree with using the rumble strips in the country. Even not tired and fully alert you're going to hear that wonderful sounds at some point.

The best use I've seen is on two lane highways​ where a mini rumble is punched in down the center line between strips. I've also seen this on multi lane highways. two rumble bumps about 6" wide?

Good stuff

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#13

Re: California Drivers Are Saying Goodbye to Botts' Dots

05/30/2017 7:41 AM

Perhaps they should replace them with these:-

https://en.wikipedia.org/wiki/Cat%27s_eye_(road)

These things are very robust, reflective (with various colours) and you know when you run over them.

The concept of these alternative road markings, is very good. Especially in poor weather conditions and at night. As mentioned by others.

I'm not sure whether any statistics have been gather, on their effectiveness with regard to road safety. But my feeling, is that it should be very significant.

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