Double Yellow Lines

[roadman]

I've seen single yellow lines in Pennsylvania and Massachusetts.

Single yellow center lines are still fairly common in Massachusetts on streets and roads that are under local jurisdiction.  It's an excellent example of the "penny wise, pound foolish" attitude of local government, who somehow believe that placing a single line is much less expensive than placing a double line.

[Duke87]

In many rural Connecticut towns single yellow lines are common on the backroads. I also have wondered the difference.

The difference is the town spends half as much money on paint. There is no difference in legal meaning.

Another reason for the practice might be that single yellow line roads tend to be fairly narrow, so using only one yellow line also makes it that much more realistically possible to stay on your side of it.

Compare this double-yellow road, where the way you drive it is you drive down the middle and then slow down and scooch over to the right when there's an oncoming car, to this single-yellow road, where you stay on your side.

[jakeroot]

Both single and double are common in Canada.  I've always wondered what the difference is.

In my experience living in Vancouver, single yellow allows passing with caution. There are very few examples of dashed yellow. With that said, highways (especially rural) use double yellow for emphasis, and as such, dashed yellow is common in those areas.

[roadfro]

In many rural Connecticut towns single yellow lines are common on the backroads. I also have wondered the difference.

The difference is the town spends half as much money on paint. There is no difference in legal meaning.

The material cost difference is half, but labor is the same (and labor is where a good chunk of the total cost comes from anyway).

There is a difference in legal meaning, since a single solid line has no legal meaning (at least if you go by the MUTCD).

[roadman]

In Massachusetts at least, no passing rules cannot be enforced by police if the roadway is striped with only a single solid yellow center line.

[Arkansastravelguy]

While driving through Sequoyah Co Oklahoma today I saw several county roads off OK101 with single yellow lines


iPhone

[jakeroot]

In Massachusetts at least, no passing rules cannot be enforced by police if the roadway is striped with only a single solid yellow center line.

Not sure what regulations (if any) Mass imposes on single yellow lines, but in British Columbia, you are legally allowed to overtake, but with greater caution then with dotted.

[realjd]

It's historical. In the past, a dashed center line was always present and the color depended on the state (often white). A yellow line on your side of the center line denoted no passing. What is now a double yellow was then double yellow solid lines with a dashed white line in between. They eventually ended up removing the dashed line and we still have the double yellow.

There are some pictures of the Philippines posted on here that show this. They apparently still do it like this sometimes there. And if you go check out street view pictures of New Zealand, they use a variant of this as well.

[ET21]

I've seen it where a single yellow line is used for a forbidden shoulder (the shoulder is too small for someone to pull over and use)

[mcdonaat]

I'm personally in favor of a double yellow line. Although, around here, people pass whenever they want to anyways.

[jbnv]

Both single and double are common in Canada.  I've always wondered what the difference is.

I was in Victoria, BC, on Saturday. Went from the cruise ship port to downtown. Don't recall seeing anything but single yellow lines.

[jakeroot]

Both single and double are common in Canada.  I've always wondered what the difference is.

I was in Victoria, BC, on Saturday. Went from the cruise ship port to downtown. Don't recall seeing anything but single yellow lines.

They're mostly seen on rural highways and large thoroughfares without hard medians...otherwise, single-yellow.

[mcmc]

What's the deal with the single broken yellow lines used on low-volume residential streets? You see them all over Southern California. They're obviously indicating direction of travel, and they can't be indicating that passing is permitted.

[DaBigE]

What's the deal with the single broken yellow lines used on low-volume residential streets? You see them all over Southern California. They're obviously indicating direction of travel, and they can't be indicating that passing is permitted.

Why can't they indicate passing as being permitted?

Standard:
01 The general functions of longitudinal lines shall be:
A.A double line indicates maximum or special restrictions,
B.A solid line discourages or prohibits crossing (depending on the specific application),
C.A broken line indicates a permissive condition, and
D.A dotted line provides guidance or warning of a downstream change in lane function.

Madison, WI has a few roads marked only with a single broken yellow as well, especially in office parks like the one I work in.

[jakeroot]

What's the deal with the single broken yellow lines used on low-volume residential streets? You see them all over Southern California. They're obviously indicating direction of travel, and they can't be indicating that passing is permitted.

Why can't they indicate passing as being permitted?

SoCal has major issues with people avoiding freeways by using residential streets as a bypass. Given this, some residential streets can get quite busy during rush hour and thus dividing lines (regardless of what they indicate) are a pretty helpful traffic control tool. Most cities don't have this issue (but that's not to say they can't).

[roadman]

It's historical. In the past, a dashed center line was always present and the color depended on the state (often white). A yellow line on your side of the center line denoted no passing. What is now a double yellow was then two double yellow solid lines with a dashed white line in between. They eventually ended up removing the dashed line and we still have the double yellow.

Not quite.  Prior to the 1961 MUTCD, a single center line was normally used on undivided roads.  Whether the line was dashed or solid was up to the agency that maintained the road, but a single solid line was often used at locations (like hills and curves) where passing was discouraged (at locations where they wanted to prohibit passing, the restriction was communicated with signs).  BTW, all center line markings were typically white before issuance of the 1961 MUTCD.

In the US, the dashed white center line with a solid yellow line on each side configuration was common in several western states for some time but was not typically used on the East Coast.  This configuration, which can be seen in several period movies such as the original (1972) Vanishing Point was actually an unintentional consequence, and very literal interpretation, of the no passing zone illustrations in the 1961 MUTCD.  The MUTCD illustrations were replaced with the current double yellow center line ones starting with the 1971 edition.  However, many states had adopted the present standard by the mid to late 1960s.

Source - 1988 discussion with long-time (and long since retired) MassDPW sign and pavement marking engineer

[BamaZeus]

In many rural Connecticut towns single yellow lines are common on the backroads. I also have wondered the difference.

Growing up, I remember Bridgeport had several single lined streets.   Park Avenue and Madison Avenue stand out to me as having had single lines through the 70s and 80s.  It just stood out to me as being unusual, but I never knew if there was any good reason behind not having the double lines instead.

[KEK Inc.]

South of Anacortes, WA, on SR-20, the wide-spaced WSDOT double yellow gets filled to a very thick single solid yellow line at turns where a left turn isn't permitted.  There's signs that indicate a left turn is illegal through thick yellow line (I don't recall the exact nomenclature). 

Unfortunately, street view shows the area before construction was done.

[1995hoo]

It's historical. In the past, a dashed center line was always present and the color depended on the state (often white). A yellow line on your side of the center line denoted no passing. What is now a double yellow was then double yellow solid lines with a dashed white line in between. They eventually ended up removing the dashed line and we still have the double yellow.

There are some pictures of the Philippines posted on here that show this. They apparently still do it like this sometimes there. And if you go check out street view pictures of New Zealand, they use a variant of this as well.

I remember back in the 1970s there was a segment of North Carolina Route 12 on Hatteras Island south of the lighthouse that had a double yellow line with a dashed yellow line in between. I don't have any pictures, of course (among other things, I was a little kid). I assume they were just lazy when painting the solid lines.

[cl94]

During the short time I lived in Columbus, Bexley, OH had them everywhere. Funny, because one would think that a city full of millionaires would have proper road markings.

[jakeroot]

South of Anacortes, WA, on SR-20, the wide-spaced WSDOT double yellow gets filled to a very thick single solid yellow line at turns where a left turn isn't permitted.  There's signs that indicate a left turn is illegal through thick yellow line (I don't recall the exact nomenclature). 

Unfortunately, street view shows the area before construction was done.

Same story along 99 south of Federal Way. Solid line for just a little while as the speed limit ups to 50 w/o a center lane.

That GSMV link above shows the solid 18-inch line.

[mrsman]

What's the deal with the single broken yellow lines used on low-volume residential streets? You see them all over Southern California. They're obviously indicating direction of travel, and they can't be indicating that passing is permitted.

Why can't they indicate passing as being permitted?

They actually indicate both items:  direction of travel and that passing is permitted.  Usually, the lowest volume streets have no yellow line at all.  Moderately busy streets would have the dashed yellow.

I found the dashed yellow to be very helpful way of dividing the traffic flows, particularly if a street was just wide enough for two passing cars.  The markings told you to stay on your side of the line.

The most narrow streets, like a lot of the streets in the older parts of L.A., did not have a dashed yellow if the street were not wide enough that 2 directions could drive through comfortably at speed limit - even if moderately busy.  There are many parts of town where if two cars were approaching the same block in opposite directions, one guy had to pull into a parking spot to let the other pass.

[realjd]

It's historical. In the past, a dashed center line was always present and the color depended on the state (often white). A yellow line on your side of the center line denoted no passing. What is now a double yellow was then two double yellow solid lines with a dashed white line in between. They eventually ended up removing the dashed line and we still have the double yellow.

Not quite.  Prior to the 1961 MUTCD, a single center line was normally used on undivided roads.  Whether the line was dashed or solid was up to the agency that maintained the road, but a single solid line was often used at locations (like hills and curves) where passing was discouraged (at locations where they wanted to prohibit passing, the restriction was communicated with signs).  BTW, all center line markings were typically white before issuance of the 1961 MUTCD.

In the US, the dashed white center line with a solid yellow line on each side configuration was common in several western states for some time but was not typically used on the East Coast.  This configuration, which can be seen in several period movies such as the original (1972) Vanishing Point was actually an unintentional consequence, and very literal interpretation, of the no passing zone illustrations in the 1961 MUTCD.  The MUTCD illustrations were replaced with the current double yellow center line ones starting with the 1971 edition.  However, many states had adopted the present standard by the mid to late 1960s.

Source - 1988 discussion with long-time (and long since retired) MassDPW sign and pavement marking engineer

Page 7 of this chart has a breakdown of state striping colors in 1949.
https://ceprofs.civil.tamu.edu/ghawkins/MUTCD-History_files/MarkingColorEvolution.pdf

It lists the center line color and style and passing "barrier" line color and style by state. Texas was the most interesting IMO. They used stone chips embedded in the asphalt for the center line and used a yellow dashed line to indicate no passing.

[roadman]

Interesting find realjd - thanks for sharing that.

[doogie1303]

In many rural Connecticut towns single yellow lines are common on the backroads. I also have wondered the difference.

I'll second that, growing up in CT, over 20 years the rural road I lived on started out with no line, then got a single yellow line for a while, then got upgraded to a double yellow line, was repaved and downgraded to a single yellow line again to which I believe it is still today.

If I recall, when it had the double yellow line the road seemed too narrow. I think the reason why they use the single line is to save lane space.