Regional Boards > Pacific Southwest

California's use of the white line J "break" before exits discontinued?

(1/1)

MrAndy1369:
This might seem like an odd question, but having grown up in California, I always noticed a small "J-style" break/divide about 100-250 ft prior to a freeway exit in the white line/lane on the side of the freeway. Here's an example: https://www.google.com/maps/@36.0799492,-120.1062679,3a,75y,311.42h,98.29t/data=!3m6!1e1!3m4!1sUBHcwseUz8YUQwnDUxRX9Q!2e0!7i16384!8i8192.

However, looking at new freeways/exits on Google Street View lately reveals that the "J-style" break (not sure what to call it) isn't used in the traditional way. Would this mean the "J-style" is being discontinued/phased out?

I noticed that none of the other states do the same thing.

Curious minds want to know!

cl94:
Quoting the California MUTCD's most recent revision, effective March 30, 2021:


--- Quote from: 2014 California MUTCD Revision 6, Chapter 3B ---A flared Right Edge Line 150 ft in advance of an exit ramp, is recommended where climatic conditions, such as areas that experience heavy fog, may require additional guidance. In areas that normally do not experience these conditions, a continuous edge line may be used.
--- End quote ---

The break before exits was intended to alert drivers to an exit during periods of dense fog, specifically Tule fog. It would make sense if it was being restricted to high-fog regions like the Central Valley. Caltrans District 3 put out a press release a few years ago explaining the line break, as well as countdown markers in the Central Valley.

MrAndy1369:
Interesting! Thanks for the explanation; I wouldn't have guessed it was related to weather/fog. I've been to plenty of areas in California, and have seen the "J" flare everywhere pretty much, in Northern and Southern California.

But, seeing a lot of reconstructed/re-painted freeways, I do notice a diminishing amount of "J" flares. This can be confirmed by using historical Google Street View images and seeing the "J" flare prior to roadwork being done. Seems like CA is now dedicating the "J" flare to only be used for where there's tendencies of heavy fog or other extreme weather. Very interesting.

jtespi:
I'm glad I found this thread on the topic. I was exploring California on GSV and was wondering what was up with all those odd white shoulder lines before exits.

In the old thread "Striping Fails/Mistakes" (shown below), Jake Root pointed out that there was a PDF once available from CalTrans that discussed the practice. The official name for the practice is "flared right edgelines."
Does anyone know where to find an online copy of that PDF? The link Jake posted back in 2016 is dead and just goes to the traffic operations page of the CalTrans website.


--- Quote from: jakeroot on May 14, 2016, 02:35:06 PM ---
--- Quote from: kendancy66 on May 14, 2016, 02:30:07 PM ---
--- Quote from: colinstu on June 22, 2015, 07:14:46 PM ---
--- Quote from: SignGeek101 on June 22, 2015, 07:11:40 PM ---https://goo.gl/maps/CUw5V

I doubt this was intentional.

--- End quote ---

California does that for upcoming exits. Something to do with there being heavy fog and if you can barely see, you can at least see the lines / that pattern in them.

--- End quote ---

I though this marking was to discourage cars from stopping on the part of the shoulder that is too close to the exit off ramp.

--- End quote ---

It's for fog. The markings are more heavily used in Northern California where fog is a bigger issue. See page 52 of 81 of this PDF, where they are called "flared right edgelines": http://goo.gl/eZ3Gsl

--- End quote ---

jeffe:
I've heard this gap in the shoulder line referred to as a "fog break".

It seems that the standard practice for District 4 (San Francisco Bay Area) is to use the break at standard exits, but omit this break where there is an exit only lane. 

I'm thinking the rationale is that the exit only lane makes the presence of the exit obvious.

Navigation

[0] Message Index

Go to full version