Down here in San Diego County, I've lately seen various lesser highways updated with new center lane markings, like this:
https://maps.app.goo.gl/76a8ukCXML6g6e5SA (https://maps.app.goo.gl/76a8ukCXML6g6e5SA)
There are two sets of double lines, and more recently candlesticks have been put up between them, but the interesting thing is that when there is a side street, or even a major driveway, there is a break in the double line on the side away from the side street, indicating that the break is there for the drivers on that side of the road.
I don't see anything in MUTCD like this. Is this something unique to California, or Southern California?
I've seen double sets of double yellow lines used like this before where they are trying to keep traffic separated because of head-on collision concerns.
This sort of lane configuration is normally treated like an island that you are not supposed to cross, which means people couldn't turn into driveways. Having the gaps in the lines would allow people to turn in the driveways.
As mentioned, in California it is illegal to turn left across those double double yellow lines. Legally they're the same as if the state put a jersey barrier down the middle.
It's obvious that two sets of double lines implies more emphasis than one set. But what does the break in one of the double lines mean? If you couldn't turn left into the side road or out of it, there would be no purpose to the break, as it would be an ordinary RIRO. So it must mean you can do one of those turns or the other or both. My guess is that you can do both. The only reason for not putting a break into both double lines is that you don't want to indicate to drivers on the same side as the side road that they can use that break to, say, make a U turn.
So am I interpreting these lines correctly? Is this a new standard, an old standard, or at least a common thing, in other places? Or is it just some new-fangled idea that CalTrans District 11 dreamt up?
The California double double yellow centerline isn't unique; Missouri does it on the shared four lane section of MO 5 between Camdenton and Lebanon. Streetview (https://maps.app.goo.gl/FmhVAF8FF4KTX6s99)
Missouri has a triple yellow centerline for some of the other shared four lane corridors.
Example the shared four lane section of US 160 west of Poplar Bluff (https://maps.app.goo.gl/He8DNME3DwcqL4327)
Example on the shared four lane section of US 63 south of Rolla (https://maps.app.goo.gl/7m5ybq4DYQx9tcBe7)
How about reflectors mounted on an overpass to denote lanes? There are a few occurrences of this on I-57 in far southern Illinois.
Example 1 (https://maps.app.goo.gl/r7drCXzgQZoCEp5o8)
Example 2 (https://maps.app.goo.gl/qHqxHDyCUUjL3Tze7)
Example 3 (https://maps.app.goo.gl/JpFSCptr98ZKArjj6)
Quote from: pderocco on July 23, 2024, 05:02:05 PMIt's obvious that two sets of double lines implies more emphasis than one set. But what does the break in one of the double lines mean? If you couldn't turn left into the side road or out of it, there would be no purpose to the break, as it would be an ordinary RIRO. So it must mean you can do one of those turns or the other or both. My guess is that you can do both. The only reason for not putting a break into both double lines is that you don't want to indicate to drivers on the same side as the side road that they can use that break to, say, make a U turn.
So am I interpreting these lines correctly? Is this a new standard, an old standard, or at least a common thing, in other places? Or is it just some new-fangled idea that CalTrans District 11 dreamt up?
They did an interesting variant of this in my town in order to allow driveway access for adjacent homeowners. I believe that the CA rule that a pair of double-yellow lines signifies a median that may not be crossed means that unless have enough space to include a "suicide" double left turn lane, this is the only other legal way to allow turns across a less-than-lane-width median.
https://www.google.com/maps/@37.9480116,-122.0707159,3a,75y,267.13h,89.01t/data=!3m6!1e1!3m4!1sKNbno9V_MrxC-v1gZJQUaQ!2e0!7i16384!8i8192?coh=205409&entry=ttu
An example of another area in my town where they *did* paint the suicide lane to allow turns, but the "lane" is only a few feet wide:
https://www.google.com/maps/@37.9428163,-122.0821473,3a,75y,180.29h,81.18t/data=!3m6!1e1!3m4!1sNV2f7rCetqP6sE_Gb7rkNg!2e0!7i16384!8i8192?coh=205409&entry=ttu
I'm not sure which is better.
There are a few examples of these (with the candlesticks in the middle) around the Seattle area, mostly to deter drivers from making time-consuming left turns.
I think it's worth emphasizing that these double double yellow lines aren't just for emphasis or to "deter" people making left turns. When I said that legally they're the same as a jersey barrier, I meant it. As in, if a cop sees you make a left turn across one, you'll get a ticket. This actually happened to one of my driver's ed teachers!
Here's another thread on the topic:
Innovative, Unique, or Strange Lane Markings
https://www.aaroads.com/forum/index.php?topic=18816.0
NJ has a double-double yellow on US 322 for about 20 miles. The width is about 8 feet apart with a rumble strip down the middle. Unlike other states, NJ doesn't have a law or other restriction regarding left turns across double-double yellows, and many motorists will use it as a narrow 2 way left turn lane. However, at intersections with traffic lights, in most cases no left turns are permitted as jughandles off to the right are available.
Quote from: vdeane on July 24, 2024, 09:09:42 PMI think it's worth emphasizing that these double double yellow lines aren't just for emphasis or to "deter" people making left turns. When I said that legally they're the same as a jersey barrier, I meant it. As in, if a cop sees you make a left turn across one, you'll get a ticket. This actually happened to one of my driver's ed teachers!
In this case, though, the break in the double double still leaves a single double, but you're allowed to cross it to and from the side of the highway that has the break. This seems to me the sort of thing that needs to be legally defined somewhere, and publicized so that people know the rules. Which was the point of my original question.
Quote from: jdbx on July 24, 2024, 04:55:07 PMQuote from: pderocco on July 23, 2024, 05:02:05 PMIt's obvious that two sets of double lines implies more emphasis than one set. But what does the break in one of the double lines mean? If you couldn't turn left into the side road or out of it, there would be no purpose to the break, as it would be an ordinary RIRO. So it must mean you can do one of those turns or the other or both. My guess is that you can do both. The only reason for not putting a break into both double lines is that you don't want to indicate to drivers on the same side as the side road that they can use that break to, say, make a U turn.
So am I interpreting these lines correctly? Is this a new standard, an old standard, or at least a common thing, in other places? Or is it just some new-fangled idea that CalTrans District 11 dreamt up?
They did an interesting variant of this in my town in order to allow driveway access for adjacent homeowners. I believe that the CA rule that a pair of double-yellow lines signifies a median that may not be crossed means that unless have enough space to include a "suicide" double left turn lane, this is the only other legal way to allow turns across a less-than-lane-width median.
https://www.google.com/maps/@37.9480116,-122.0707159,3a,75y,267.13h,89.01t/data=!3m6!1e1!3m4!1sKNbno9V_MrxC-v1gZJQUaQ!2e0!7i16384!8i8192?coh=205409&entry=ttu
An example of another area in my town where they *did* paint the suicide lane to allow turns, but the "lane" is only a few feet wide:
https://www.google.com/maps/@37.9428163,-122.0821473,3a,75y,180.29h,81.18t/data=!3m6!1e1!3m4!1sNV2f7rCetqP6sE_Gb7rkNg!2e0!7i16384!8i8192?coh=205409&entry=ttu
I'm not sure which is better.
I don't get the purpose of the first one. They've inexplicably introduced a reversible lane marking for a tiny area that can't be more than three feet wide and 100-200 feet long. You can legally turn across a single double yellow anyway, so they should've just left the line at that and let the travel lanes be a little wider over that distance.
The second one makes total sense to me given the context.
I think I agree with the above, at least as far as the first example. There is no purpose to this painting. Just leave the lanes as they are.
I don't like the narrow suicide lane example. It is painted like a lane, but is not wide enough. Given that there is actual concrete here, I think just a regular double yellow would do the job.