Experimental Merge Sign

[Mergingtraffic]

CT DOT is trying a new merge sign.

http://www.ct.gov/dot/cwp/view.asp?a=1384&q=259518

[corco]

The thing I don't like about that sign is that it doesn't establish which lane gets priority. If I'm in the right lane and there's a RIGHT LANE ENDS sign, the burden is on me to get in the left lane, and if I run into a car in the left lane while trying to merge the accident will be my fault.

I suppose if the intent is to enforce (what I think is unenforcable, because everyone will do it with a cop watching and it generally happens at low speed) zipper merging, then that's cool since that's the most efficient way to merge, but from the stance of a law enforcement official it's way easier to put right of way into a particular lane.

This doesn't seem to put priority on either lane, which I don't see as a good thing.

[andytom]

The experimental sign specifies what is actually happening in most of these merges; that 2 lanes are becoming one and that, when the lane line ends, single lane rules apply even though the lane is initially 24 ft wide.  That means that, with any pair of vehicles, it is the responsibility of the trailing one not to run into the leading one, even if it's trailing by only a bumper.  This puts the priority on vehicles based on longitudinal position rather than lateral position (ie. on the leading vehicle rather than the lane the vehicle is in).

The only reason I can think of where a lane needs to be given priority in a merge is when one lane has an average speed significantly different from the other such as a truck climbing lane.

--Andy

[corco]

That makes sense. I didn't think about it that way. What if you have two vehicles perfectly parallel to each other, though?

[andytom]

The one who figures that out first gives (or takes), or the skid marks will tell who to cite.

--Andy

[corco]

The one who figures that out first gives (or takes), or the skid marks will tell who to cite.

--Andy

So in the highly unlikely event that there's two suicidal people both parallel to each other that opt to merge into one another (nobody giving or taking or braking), do you cite them both?

[shoptb1]

CT DOT is trying a new merge sign.

http://www.ct.gov/dot/cwp/view.asp?a=1384&q=259518

ODOT has used a sign similar to what CT DOT is proposing for a long time:


http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=columbus,+oh&sll=39.689884,-79.25005&sspn=0.087183,0.154324&ie=UTF8&hq=&hnear=Columbus,+Franklin,+Ohio&ll=39.984897,-83.118546&spn=0.010785,0.01929&t=h&z=16&layer=c&cbll=39.984991,-83.118552&panoid=HRpIvqJUljifYRI0cg9gPw&cbp=12,356.23,,0,0.6

However, I see a fundamental difference between when this MERGE sign would be used vs. the LANE ENDS (W4-2) sign.   In the instance above, both lanes really have right-of-way, and should "blend".  The LANE ENDS merge type (W4-2) indicates that one lane vs. another is ending and that the burden of merging is placed upon those that are in the lane that is ending.  The right-of-way belongs to those that are in the continuing lane.

[Duke87]

Here's a pair of them that's been posted in the field for about 2-3 years now.

[andytom]

The one who figures that out first gives (or takes), or the skid marks will tell who to cite.

--Andy

So in the highly unlikely event that there's two suicidal people both parallel to each other that opt to merge into one another (nobody giving or taking or braking), do you cite them both?

Yeah, if they didn't kill each other first.

--Andy

[Truvelo]

This is how we do it over here.

[Hellfighter]

To me, it looks confusing. It looks like both lanes are combining into one, instead of, lets say, the right lane merging into the left lane. I like this one better...

[Kacie Jane]

To me, it looks confusing. It looks like both lanes are combining into one, instead of, lets say, the right lane merging into the left lane.

But that's exactly the point.  Both lanes are combining into one -- neither one has priority, whereas when one lane ends, the other has priority.

[roadfro]

ODOT has used a sign similar to what CT DOT is proposing for a long time: [Google Street View Link]

However, I see a fundamental difference between when this MERGE sign would be used vs. the LANE ENDS (W4-2) sign.   In the instance above, both lanes really have right-of-way, and should "blend".  The LANE ENDS merge type (W4-2) indicates that one lane vs. another is ending and that the burden of merging is placed upon those that are in the lane that is ending.  The right-of-way belongs to those that are in the continuing lane.

The ODOT sign linked is very similar to the CT DOT design being studied, except that it doesn't show the lanes being dropped. In the application linked in the example, however, the sign shows a merge condition in what appears to be an added lane situation at first glance. Seeing that the two interior lanes merge further downstream, it's a unique situation with a unique sign that accurately portrays the situation--however, it may not necessarily be immediately understood by those unfamiliar with the geometry, as it could be misinterpreted to mean that the two roadways are simply converging into one.  The CT DOT design probably wouldn't fare much better in this case without modification.

[Stephane Dumas]

To me, it looks confusing. It looks like both lanes are combining into one, instead of, lets say, the right lane merging into the left lane. I like this one better...

+1, it's been used in some Canadian provinces since a couple of years

[roadfro]

To me, it looks confusing. It looks like both lanes are combining into one, instead of, lets say, the right lane merging into the left lane. I like this one better...

The experimental design being used by Connecticut really only makes sense if the road's two lanes are converging into one, which appears to be the case in a few of the examples posted here.

The standard lane ends signs make much more sense when a lane must merge into a through travel lane. The standard symbol has the added benefit of being applicable in situations involving more than just two lanes (the terminating lane and the adjacent one).

[Hot Rod Hootenanny]

CT DOT is trying a new merge sign.

http://www.ct.gov/dot/cwp/view.asp?a=1384&q=259518

ODOT has used a sign similar to what CT DOT is proposing for a long time:


http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=columbus,+oh&sll=39.689884,-79.25005&sspn=0.087183,0.154324&ie=UTF8&hq=&hnear=Columbus,+Franklin,+Ohio&ll=39.984897,-83.118546&spn=0.010785,0.01929&t=h&z=16&layer=c&cbll=39.984991,-83.118552&panoid=HRpIvqJUljifYRI0cg9gPw&cbp=12,356.23,,0,0.6

However, I see a fundamental difference between when this MERGE sign would be used vs. the LANE ENDS (W4-2) sign.   In the instance above, both lanes really have right-of-way, and should "blend".  The LANE ENDS merge type (W4-2) indicates that one lane vs. another is ending and that the burden of merging is placed upon those that are in the lane that is ending.  The right-of-way belongs to those that are in the continuing lane.

Though I was under the impression that ODOT was phasing that sign (and type of lane mergers for that matter) out.  That (kind of) sign used be seen on I-71 SB @ I-270 (North) and SB between I-670 and Broad St.  Not anymore.

[TXtoNJ]

Yeah, I don't like this sign. It looks unfortunately too much like something else (dirty minds need only apply)

[Bickendan]

The other ODOT's example: http://maps.google.com/?ie=UTF8&ll=45.289977,-122.997844&spn=0,0.011362&t=k&z=17&layer=c&cbll=45.289912,-122.997935&panoid=cH-x4YN1ZgLIvHcZgtqnBA&cbp=12,228.65,,0,2.79

[Mergingtraffic]

The other ODOT's example: http://maps.google.com/?ie=UTF8&ll=45.289977,-122.997844&spn=0,0.011362&t=k&z=17&layer=c&cbll=45.289912,-122.997935&panoid=cH-x4YN1ZgLIvHcZgtqnBA&cbp=12,228.65,,0,2.79

I like that sign, but it looks like it would be after some previous warning signs.  I also like the arrows on the road itself too.

[Bickendan]

I'm thinking there are others, but I didn't go far enough back on the route to find them.

[roadfro]

The other ODOT's example: http://maps.google.com/?ie=UTF8&ll=45.289977,-122.997844&spn=0,0.011362&t=k&z=17&layer=c&cbll=45.289912,-122.997935&panoid=cH-x4YN1ZgLIvHcZgtqnBA&cbp=12,228.65,,0,2.79

I like that sign, but it looks like it would be after some previous warning signs.  I also like the arrows on the road itself too.

That example seems rather ambiguous. The arrows pointing down would seem to indicate that a merge is required at the point of the sign (like the downward angled arrow underneath a crosswalk sign indicates the crosswalk is adjacent to the sign). In this particular example, there's a bit more distance after the signs until the lanes actually merge together.

There is a set of diamond warning signs that says "LANES MERGE 1000 FT" ahead of these signs. The most clear indication from this installation is the pavement arrows...ODOT should've used three pairs of arrows instead of just one.

[Bickendan]

ODOT isn't fond of using merge arrows as a rule. I've seen them here and there, but by and large, they're not used at all.

[Bryant5493]

^^ Georgia's sporadic in the use of "merge arrows" as well. Wished they were used more, though.


Be well,

Bryant