Signing a merge and a lane drop—when no original lanes continue through

[briantroutman]

At Williamsport, PA, southbound US 15 merges with northbound US 220, and both are co-signed at the merge point with I-180 East. In close proximity (slightly to the east) is an interchange with a surface road, Maynard Street.

(This diagram isn't to scale and the geometry has been changed somewhat for the purposes of illustrating the "through"  movement, although all of the relationships of the lanes are portrayed accurately and the signs and markings are exactly as they appear in reality.)

(Click image to view full-size)


My concern is how the lane drop is handled in both the signage and the lane markings. On southbound US 15, Maynard Street is signed "EXIT ONLY"  over Lane D. This pattern is repeated at the 1 mile and 1/2 mile intervals before the Maynard Street exit. However between the 1/2 mile interval and the Maynard Street exit gore, Lane D ends. Two additional sign assemblies follow (at approximately 1/4 mile and at the exit gore) showing Lane C signed as "EXIT ONLY"  for Maynard.

So in reality, none of the US 15 lanes (C and D) continue as through to the 180/220/15 conjunction–all through traffic must merge left to continue. However at the beginning of this sequence, I doubt you'd sign Lane C as "Maynard St - EXIT ONLY"  and Lane D as "LANE ENDS - 1/2 MILE" ...even though that would be completely accurate.

I have to imagine this is a fairly common situation. How is it handled elsewhere, and how would you suggest signing it here?

[hotdogPi]

I don't think a lane ending and an exit only within 1 mile is common.

[Ned Weasel]

I have to imagine this is a fairly common situation. How is it handled elsewhere, and how would you suggest signing it here?

I would say the simplest solution is to remove all of the guide signs shown in your diagram on SB US 15 in advance of the convergence, except for the the signage for Lane E (SB US 220/Lock Haven).  Sometimes less is more, especially when "more" is confusing and/or misleading.  If you like having more information in advance, then I would withhold all references to lanes C and D until after the convergence--that is, the down arrows and "EXIT ONLY" tabs referring to lanes C and D should be removed in advance of the convergence.  There should also be a "RIGHT LANE ENDS" sign of some sort.

The convergence of NB US 69 and NB I-35 in Lenexa, KS used to be a similar situation, as the two lanes from NB US 69 converged with the three lanes from NB I-35, and (counting them all as NB I-35 lanes) the #5 lane ended shortly after the convergence and the #4 lane became an exit-only lane for 75th Street about a mile after the convergence.  75th Street was not referenced on NB US 69 until after the convergence.  This has, however, all been reconfigured (https://maps.google.com/?ll=38.985133,-94.704852&spn=0.018614,0.042272&t=k&z=15).  I can't think of something closer to your example off the top of my head, but it doesn't seem like an uncommon situation.

[Revive 755]

I'm leaning towards dropping the 'exit only' for Maynard Street until the third assembly, and using 'keep left' or 'merge left' for I-180/US 220/US 15.

[vtk]

This is similar to I-71 northbound where it joins I-70 eastbound and then there's the exit to Front St (current configuration).  The Front St exit isn't even signed until the two Interstates join, though.

[bzakharin]

How about a diagrammatic? Is there standard signage for merging diagrammatics?

Would something like this work in real life?:

[hotdogPi]

How about a diagrammatic? Is there standard signage for merging diagrammatics?

Would something like this work in real life?:

In your diagram, one lane continues through.

[bzakharin]

In your diagram, one lane continues through.

I was going for simplicity. How about this?

[roadman65]

I-280 in Newark, NJ could use them in both directions between the  Garden State Parkway and First Street.  Going EB all three through lanes exit onto First Street, while the merging lanes from the Garden State Parkway become the two new through lanes.

Then going WB the two through lanes merge in with the three new lanes (left merge) from First Street where these become the three through lanes after the exit for the GSP.  The two original lanes of I-280 here exit onto the Parkway in reverse fashion of the EB situation.

[Duke87]

I don't think the real world situation is as confusing as this diagram implies, since the geometry has the through movement for 15 south obviously feeling more like a ramp than a mainline, i.e., a need to merge is not unexpected.

Nonetheless, given the circumstances I wonder if it might not be more pragmatic to stripe a merge between lanes B and C and have lane D drop at the exit. Or, alternatively, end lane D sooner and forget about signing Maynard St from 15 until after the roadways join.

[Scott5114]

The Maynard Street sign should be above Lane C the entire time. Lane D should have a yellow "Lane Ends/Merge Left" sign over it. Add "Keep Left" under the pull through until the merge. Done.

[jemacedo9]

I drive through there once a month.  What makes this more confusing is that there is a YIELD sign, with a LEFT LANE sign underneath that, where the 4 lanes collapse to three.  I think that PennDOT is trying to imply that Lane C ends and should merge into Lane B. That would leave Lane D solely reserved for the Maynard St Exit, as the BGSs imply.  The problem?  The lane striping is as illustrated above, which implies that Lane D ends, and Lane C becomes the Maynard St Exit only lane.  It's confusing, for sure.

[SignBridge]

Roadman, I've also noted the problem you described on I-280. Last I drove thru there in January 2013, new signs had recently replaced the old 1970's era signs eastbound at least. Looking at Google Earth, I see there are a total of 4 sets of overhead signs up to the split, which isn't bad.

Westbound needs improvement though. Only one set of signs exist before the split. The pull-thru signs for I-280 advising left 3 lanes is ridiculously small. A much larger, more prominent sign is needed there for the thru Interstate route. Also, the Garden State Pkwy. needs to be spelled out, instead of just the logo shown there now, with no destinations. For a major interchange, it needs to be more prominently displayed.

I for one do not like diagrammatic signing. I think some slightly more imaginative conventional signs would work fine if NJDOT would get their act together and sign it more aggressively.

[Zeffy]

Here's my re-design for I-280... first up is eastbound:



Once the lanes prepare to split for their respective destinations:


And for westbound...


The key here is to repeat these signs every 1/4 of a mile until the split happens. Eastbound is probably fine the way it is. But like others said, westbound could use some adjustment. The way I signed all of the lanes meant I had to use a different EXIT ONLY layout unlike the other signs.

[SignBridge]

Not bad Zeffy! Similar to what I would do there.