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D7 Removing "Botts Dots"??

Started by AndyMax25, January 04, 2017, 02:05:45 PM

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AndyMax25

I've started noticing long stretches of freeway in D7 where "Botts Dots" have clearly been removed.  In particular along the Santa Monica Freeway between Lincoln and around La Brea and along the Santa Ana portion of the 101 in Downtown LA between Vignes and the Four Level Interchange.  I sent in the question to D7 via twitter and got an interesting response (links below).

Question: https://twitter.com/AndyMax25/status/815655211045765120
Answer: https://twitter.com/CaltransDist7/status/816699846434422786

I was at an ITE conference last year and recall hearing the D7 director mention that they are going to be removing Botts Dots.  Her reason was because they were getting too many complaints from vehicle navigation system companies.  She stated that the companies were concerned that the vibrations from the Botts Dots were disrupting the navi systems and cause them to not function properly.  At the time I though what a silly reason to compromise safety and spend tens of thousands of dollars to remove a more than 60 year investment.

Has anyone heard about this "state-of-the-art thermoplastic lane marking material"?  Any policy directive or memo out there?


coatimundi

#1
Quote from: AndyMax25 on January 04, 2017, 02:05:45 PM
I was at an ITE conference last year and recall hearing the D7 director mention that they are going to be removing Botts Dots.  Her reason was because they were getting too many complaints from vehicle navigation system companies.  She stated that the companies were concerned that the vibrations from the Botts Dots were disrupting the navi systems and cause them to not function properly.  At the time I though what a silly reason to compromise safety and spend tens of thousands of dollars to remove a more than 60 year investment.

Wow, that's totally ridiculous. I mean, god forbid someone not be notified of their upcoming exit early enough because of the inconvenient rumbles of a safety warning device. In my view, D7 needs these more than anyone. Hopefully they're at least lumping the removals into existing projects in order to gradually remove them instead of going out just to remove them.
I think a letter to Caltrans is in order...

And maybe they're talking about this? Something that would come loose and wash into the ocean.
https://www.swarco.com/en/Products-Services/Traffic-Materials/Glass-Beads

AsphaltPlanet

^ Glass beads have been in roadway paint for a very long time.

And glass is made of sand, so it's pretty benign.  Solvents from the paints would be far more damaging to the environment than the glass.
AsphaltPlanet.ca  Youtube -- Opinions expressed reflect the viewpoints of others.

coatimundi

Quote from: AsphaltPlanet on January 04, 2017, 02:38:24 PM
^ Glass beads have been in roadway paint for a very long time.

And glass is made of sand, so it's pretty benign.  Solvents from the paints would be far more damaging to the environment than the glass.

Glass is partially made of sand, but it's a lot of other, sometimes toxic materials. I realize that I don't know enough about this particular glass to say what it's actually made of, but it's not as if glass just dissolves in water. I realize micro beads are different since they're plastic, but it's the same thing: they look like food to a lot of marine life. That's why they were banned here.

AsphaltPlanet

#4
^ Typically the most toxic component in glass is the silica sand itself.  Particles of silica sand are found in that sweet spot that will get lodged in a humans lung if inhaled.  It's possible for glass to be treated with lead or other metals, but such treatment is typically used only for special cosmetic glass, structural glass or for glass used in electronics.  Silica sand just settles to the bottom of a watercourse typically.  It is possible for glass to leach if it has been treated with metals, however, as noted above, metals are only added for special types of glass.  In fact, because there is both so little market demand for recycled crushed glass, and because of it's relatively benign properties, there is a growing movement to use glass as cover for landfilling operations.
AsphaltPlanet.ca  Youtube -- Opinions expressed reflect the viewpoints of others.

jrouse

#5
Yes, it is true that Botts dots are going away.  They have been (or will be) removed from Caltrans' standard plans.  I understand that maintenance is a major reason why.  The reason given by the district 7 director is news to me.  I'm friends with our traffic engineering branch chief, who is overseeing this, and I'll confirm it with him.

I think it's important to note that when we talk about Botts' dots, we're talking about round raised pavement markers.  We're not talking about the square pavement reflectors.  Those are not going away.   An earlier poster made reference to marking an offramp.  Reflectors are used for those purposes, not Botts' dots. 

We will be requiring striping to basically have a minimum amount of reflectivity, much like we require for signing.  We do not have any such requirement now.  Autonomous vehicle manufacturers have been talking with us about improving the visibility of our stripes.


iPhone

coatimundi

It's been discussed before, but D7, if anything, is excellent at public response. Up here, in D5, it seems like it takes a certified letter to get a response from them.

Quote
Thank you for contacting Caltrans to ask about Botts dots.  I'm responding to the email you sent today to Lauren Wonder here at Caltrans District 7 (which includes Los Angeles and Ventura counties).
Contrary to what you may have heard, Caltrans is not discontinuing the use of Botts dots.  Caltrans believes this variety of raised pavement marker is an important safety feature of California roadways.  But Caltrans does not exclusively use Botts dots for pavement marking.
For example, in some areas you may see thermoplastic striping used. This type of material is heated and applied to road surfaces in a molten state using a mechanical applicator. Immediately after application to the pavement, glass beads are applied to the striping to make it retroreflective. The striping has a slightly raised surface helpful to drivers, yet it is resistant to deformation by traffic.
Thank you for your interest in our state highway system.  Please let me know if you have other questions or comments.
Sincerely,

Michael Comeaux
Public Information Officer

AndyMax25

Quote from: jrouse on January 04, 2017, 07:15:59 PM
Yes, it is true that Botts dots are going away.  They have been (or will be) removed from Caltrans' standard plans.  I understand that maintenance is a major reason why.  The reason given by the district 7 director is news to me.  I'm friends with our traffic engineering branch chief, who is overseeing this, and I'll confirm it with him.

We will be requiring striping to basically have a minimum amount of reflectivity, much like we require for signing.  We do not have any such requirement now.  Autonomous vehicle manufacturers have been talking with us about improving the visibility of our stripes.
iPhone

jrouse, thanks for the info and for taking the time to check in with your colleague.  I know that D7 has used lane markings along PCH in the Malibu area that has a grooved surface to it, which causes a very light rumble when switching lanes.  It was definitely more subtle than Botts Dots and made a sound similar to a traditional rumble strip.

Any idea if this could be part of a new spec in addition to the reflectivity?

jrouse

I talked with our Traffic Engineering branch chief and he did confirm that Botts dots are going away.  Interestingly enough, he said FHWA was responsible for the decision because they do not consider the dots as an appropriate form of lane striping.  So they can no longer be used.  I asked him about the statement made by the District 7 director regarding the impacts of Botts dots on navigation systems and he said he had heard the same thing but it wasn't the reason for eliminating them.

As I mentioned in my earlier post we are going to be issuing standards for striping which will include retro reflectivity requirements.  We are phasing out the use of paint and will be going with thermoplastic or tape.


iPhone

myosh_tino

Quote from: jrouse on January 11, 2017, 07:02:23 AM
I talked with our Traffic Engineering branch chief and he did confirm that Botts dots are going away.  Interestingly enough, he said FHWA was responsible for the decision because they do not consider the dots as an appropriate form of lane striping.  So they can no longer be used.  I asked him about the statement made by the District 7 director regarding the impacts of Botts dots on navigation systems and he said he had heard the same thing but it wasn't the reason for eliminating them.

As I mentioned in my earlier post we are going to be issuing standards for striping which will include retro reflectivity requirements.  We are phasing out the use of paint and will be going with thermoplastic or tape.

I am saddened that Botts Dots are going away.  While I understand the importance of retro-reflectivity, the use of Botts Dots provides a sudden audible noise to drivers that they were drifting out of their lane.  This will be lost once the dots are gone and I don't think the single reflective markers between the stripes will provide a suitable alternative.  As far as the FHWA is concerned, if the dots were used in conjunction with standard striping (which is pretty standard on California's freeways), I don't understand why they would care.

By the way, Nevada and Washington were also users of Botts Dots so I'm guessing they will be phasing them out too.
Quote from: golden eagle
If I owned a dam and decided to donate it to charity, would I be giving a dam? I'm sure that might be a first because no one really gives a dam.

vdeane

In cases where Botts Dots are used instead of line striping (as is done in some places), IMO they should be banned, since they lines are difficult to see.  But I don't see a reason to ban them if they're used in addition to striping.
Please note: All comments here represent my own personal opinion and do not reflect the official position of NYSDOT or its affiliates.

cl94

Quote from: jrouse on January 11, 2017, 07:02:23 AM
As I mentioned in my earlier post we are going to be issuing standards for striping which will include retro reflectivity requirements.  We are phasing out the use of paint and will be going with thermoplastic or tape.

Will thermo/tape be a statewide standard, or will Caltrans still use paint in areas with heavy snowfall?

I also wonder how much cost is a part of this. One would think that thermoplastic/tape is quite a bit cheaper.
Please note: All posts represent my personal opinions and do not represent those of my employer or any of its partner agencies.

Travel Mapping (updated weekly)

Revive 755

Quote from: jrouse on January 11, 2017, 07:02:23 AM
I talked with our Traffic Engineering branch chief and he did confirm that Botts dots are going away.  Interestingly enough, he said FHWA was responsible for the decision because they do not consider the dots as an appropriate form of lane striping.

Maybe I'm not familiar enough with Botts dots and their use in California, but the statement would not appear to agree with the current national edition of the MUCTD:

Quote from: Option:

Retroreflective or internally illuminated raised pavement markers, or non-retroreflective raised pavement markers supplemented by retroreflective or internally illuminated markers, may be substituted for markings of other types.

That said, I did see something a couple months ago online that in some presentation FHWA attended FHWA indicated that there may be a revision coming to the MUTCD soon for pavement markings (may have been regarding retroreflectivity requirements)

Alps

Quote from: Revive 755 on January 11, 2017, 06:21:04 PM
Quote from: jrouse on January 11, 2017, 07:02:23 AM
I talked with our Traffic Engineering branch chief and he did confirm that Botts dots are going away.  Interestingly enough, he said FHWA was responsible for the decision because they do not consider the dots as an appropriate form of lane striping.

Maybe I'm not familiar enough with Botts dots and their use in California, but the statement would not appear to agree with the current national edition of the MUCTD:

Quote from: Option:

Retroreflective or internally illuminated raised pavement markers, or non-retroreflective raised pavement markers supplemented by retroreflective or internally illuminated markers, may be substituted for markings of other types.

That said, I did see something a couple months ago online that in some presentation FHWA attended FHWA indicated that there may be a revision coming to the MUTCD soon for pavement markings (may have been regarding retroreflectivity requirements)
Supplemented. Right there.

jakeroot

#14
WSDOT has mostly done away with botts dots, but they replaced them with, what are in my opinion, superior markings that keep the raised bit, but are exceptionally reflective. They're called raised rib markings, and are used in places with mostly non-snow precipitation (Washington, Oregon, Northern California, the UK, etc). Obviously Southern California doesn't get regular murky precipitation like those places, but I think these would be a worthy replacement regardless:


compdude787

Agreed. I really like the way WSDOT does their lane markings. Going over the lines sounds like you're going over rumble strips, at least if it's a solid line like you're switching into the carpool lane.

Bickendan

I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

Rothman

Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

Come to NY and see lanes totally disappear when it rains.
Please note: All comments here represent my own personal opinion and do not reflect the official position(s) of NYSDOT.

cl94

Quote from: Rothman on January 12, 2017, 08:27:22 AM
Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

Come to NY and see lanes totally disappear when it rains.

Yup. Recently, MassDOT started using standard Stimsonite markers placed in grooves, so they can't be removed by plows. They seem to be holding up. Would be nice if NYSDOT did that. The visibility difference along NY/MA 2 at the border is striking.

ODOT can't use Botts Dots because of snow. Plows would tear them up in the first winter.
Please note: All posts represent my personal opinions and do not represent those of my employer or any of its partner agencies.

Travel Mapping (updated weekly)

jakeroot

Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

I swear I saw raised rib markings down in Oregon just last week. I must have been mistaken.

Quote from: cl94 on January 12, 2017, 08:45:22 AM
ODOT can't use Botts Dots because of snow. Plows would tear them up in the first winter.

Which ODOT?

Bickendan

Quote from: jakeroot on January 12, 2017, 01:29:53 PM
Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

I swear I saw raised rib markings down in Oregon just last week. I must have been mistaken.
Not on the Banfield you didn't.
It's possible on the Baldock or East Portland, though. I'll need to check once the snow melts off.

Quote
Quote from: cl94 on January 12, 2017, 08:45:22 AM
ODOT can't use Botts Dots because of snow. Plows would tear them up in the first winter.

Which ODOT?
Any?

sparker

Quote from: Bickendan on January 13, 2017, 03:32:07 AM
Quote from: jakeroot on January 12, 2017, 01:29:53 PM
Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

I swear I saw raised rib markings down in Oregon just last week. I must have been mistaken.
Not on the Banfield you didn't.
It's possible on the Baldock or East Portland, though. I'll need to check once the snow melts off.

Quote
Quote from: cl94 on January 12, 2017, 08:45:22 AM
ODOT can't use Botts Dots because of snow. Plows would tear them up in the first winter.

Which ODOT?
Any?

The CA Division of Highways started placing Botts Dots in pavement rebates as early as the mid-60's on facilities within areas that required plowing -- but it was a relatively expensive methodology.  However, no applied pavement marker, whether reflective plastic markings or retroreflective thermoplastic strips, will last too long when subject to regular plowing, which tends to gouge below the pavement surface.  Replacing such markers or treatments is and likely will be a regular springtime activity for some time to come. 

jakeroot

Quote from: Bickendan on January 13, 2017, 03:32:07 AM
Quote from: jakeroot on January 12, 2017, 01:29:53 PM
Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

I swear I saw raised rib markings down in Oregon just last week. I must have been mistaken.

Not on the Banfield you didn't.
It's possible on the Baldock or East Portland, though. I'll need to check once the snow melts off.

I only used the 5. I drove straight from Tacoma to Keizer to see family, then straight back north.

Street View clearly shows raised rib markings along the 5 at the Terwilliger Curves as well as north of Portland approaching the Columbia River. They are slightly different raised markers than the kind used by WSDOT, but they are still unmistakably raised rib markings.

Quote from: Bickendan on January 13, 2017, 03:32:07 AM
Quote from: jakeroot on January 12, 2017, 01:29:53 PM
Quote from: cl94 on January 12, 2017, 08:45:22 AM
ODOT can't use Botts Dots because of snow. Plows would tear them up in the first winter.

Which ODOT?

Any?

I was asking cl94 because O(regon)DOT could pull off using Botts Dots (as out of date as they may be) in the Willamette Valley without too much issue. Besides this winter (unusually snowy), Portland doesn't get much snow.

WSDOT no longer uses Botts Dots, but they are still a common sight in the Seattle area. Seattle typically gets more snow than Portland, yet we've been using Botts Dots for some time without too much issue. Some cities, like Bellevue, continue to install Botts Dots for all their road markings, minus stop bars, crosswalk markings and arrows. Typically, plows aren't used to the same extent as they are back east. De-icing solution and salt are generally how roads are kept clear here. Plows are a rare sight in the Seattle area.

jeffandnicole

Quote from: sparker on January 13, 2017, 04:08:54 AM
Quote from: Bickendan on January 13, 2017, 03:32:07 AM
Quote from: jakeroot on January 12, 2017, 01:29:53 PM
Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

I swear I saw raised rib markings down in Oregon just last week. I must have been mistaken.
Not on the Banfield you didn't.
It's possible on the Baldock or East Portland, though. I'll need to check once the snow melts off.

Quote
Quote from: cl94 on January 12, 2017, 08:45:22 AM
ODOT can't use Botts Dots because of snow. Plows would tear them up in the first winter.

Which ODOT?
Any?

The CA Division of Highways started placing Botts Dots in pavement rebates as early as the mid-60's on facilities within areas that required plowing -- but it was a relatively expensive methodology.  However, no applied pavement marker, whether reflective plastic markings or retroreflective thermoplastic strips, will last too long when subject to regular plowing, which tends to gouge below the pavement surface.  Replacing such markers or treatments is and likely will be a regular springtime activity for some time to come. 

Plows are not gouging below the pavement surface.  A plow blade skims along the surface at most, with salt or other deicing material taking care of what's left on the surface. 

If you're in an area where Botts Dots are used, any other pavement marking should have a very long, useful life. 

Brandon

Quote from: jeffandnicole on January 13, 2017, 06:09:09 AM
Quote from: sparker on January 13, 2017, 04:08:54 AM
Quote from: Bickendan on January 13, 2017, 03:32:07 AM
Quote from: jakeroot on January 12, 2017, 01:29:53 PM
Quote from: Bickendan on January 12, 2017, 05:57:09 AM
I wish ODOT would adopt those. It's so hard to see the lane markers in the dark when it's raining on Portland freeways.

I swear I saw raised rib markings down in Oregon just last week. I must have been mistaken.
Not on the Banfield you didn't.
It's possible on the Baldock or East Portland, though. I'll need to check once the snow melts off.

Quote
Quote from: cl94 on January 12, 2017, 08:45:22 AM
ODOT can't use Botts Dots because of snow. Plows would tear them up in the first winter.

Which ODOT?
Any?

The CA Division of Highways started placing Botts Dots in pavement rebates as early as the mid-60's on facilities within areas that required plowing -- but it was a relatively expensive methodology.  However, no applied pavement marker, whether reflective plastic markings or retroreflective thermoplastic strips, will last too long when subject to regular plowing, which tends to gouge below the pavement surface.  Replacing such markers or treatments is and likely will be a regular springtime activity for some time to come. 

Plows are not gouging below the pavement surface.  A plow blade skims along the surface at most, with salt or other deicing material taking care of what's left on the surface. 

If you're in an area where Botts Dots are used, any other pavement marking should have a very long, useful life. 

We've discussed this with you many a time.  Plows do indeed scrape up paint.  Watch them sometime, you'll be amazed at how much sparking there can be when the blade strikes the pavement repeatedly.  Maybe it just doesn't snow enough in South Jersey for you to notice.
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

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