Unsigned U.S. Highway Segments: Intentional Policy?

[Ned Weasel]

I know that Interstate and U.S. route multiplexes have been discussed at length before (https://www.aaroads.com/forum/index.php?topic=1999.0), but I am specifically curious about unsigned segments of U.S. Highways that make the route impossible to follow without using a map, and these tend to occur where a U.S. route duplexes with an Interstate route.  The two examples that always come to mind for me are US 6 in Denver, Colorado, which I only know from maps and images, and US 169 in Johnson County, Kansas, with which I am familiar.  In both instances, following the U.S. route by signs is impossible, because their signing disappears when they become duplexed with interstates.  From the images I have seen of US 6 in Colorado, the lack of signing appears consistent enough to be intentional, but please correct me if I'm wrong.  US 169 in Kansas was recently rerouted, but signs for the highway were actually removed from segments that would have been unaffected by the rerouting (US 56/Shawnee Mission Parkway and Rainbow Boulevard).

I am wondering, are there specific policies that states use to determine when not to sign U.S. Highways concurrently with Interstates?  I know some states have highway mileage caps, but that shouldn't affect concurrent signing.  If the goal is to reduce what some may consider "sign clutter," then why are some U.S. Highways signed where they run concurrently with Interstates while others are not?  Furthermore, is this rule frequently applied to non-Interstate duplexes (such as the US 56/US 169 example in Kansas)?

A similar example is I-465 in Indiana, which has several U.S. routes running concurrently along much of its length, unsigned.  The difference, though, is that, at least from the images I have seen, it appears possible to follow these U.S. routes by signs (correct me if there are junctions where this is not true), although one would not know if he or she were joining a U.S. route in the middle of its multiplex with I-465, and I don't remember there being any reassurance shields.  This approach seems preferable for maintaining the continuity of a U.S. route while minimizing signs.  But then, do other states, such as Colorado, actually find it preferable to have a U.S. route appear to end at an Interstate and then reappear somewhere else?

[J N Winkler]

I am wondering, are there specific policies that states use to determine when not to sign U.S. Highways concurrently with Interstates?  I know some states have highway mileage caps, but that shouldn't affect concurrent signing.  If the goal is to reduce what some may consider "sign clutter," then why are some U.S. Highways signed where they run concurrently with Interstates while others are not?  Furthermore, is this rule frequently applied to non-Interstate duplexes (such as the US 56/US 169 example in Kansas)?

As far as I am aware, no policies exist at the national level, while state-level policies vary considerably in depth and detail.  I have long suspected that the process of developing signing schemes at the state level (which is essentially what a decision to sign or not to sign a US highway in a given corridor is) relies heavily on engineering judgment, rather than formal codified policies.  I also suspect that the outcomes are often not committed to paper except possibly as memoranda restricted to internal circulation in the traffic design office.

In the case of New Mexico, for example, US 85 is not signed at all while it is in both Texas and Colorado.  I think there must have been a deliberate decision to this effect but I have never been shown a memo which says, explicitly, "Do not sign US 85 and do not make signing plans for I-25 which show US 85."

A similar example is I-465 in Indiana, which has several U.S. routes running concurrently along much of its length, unsigned.  The difference, though, is that, at least from the images I have seen, it appears possible to follow these U.S. routes by signs (correct me if there are junctions where this is not true), although one would not know if he or she were joining a U.S. route in the middle of its multiplex with I-465, and I don't remember there being any reassurance shields.  This approach seems preferable for maintaining the continuity of a U.S. route while minimizing signs.  But then, do other states, such as Colorado, actually find it preferable to have a U.S. route appear to end at an Interstate and then reappear somewhere else?

Again, I suspect the decision-making processes are largely undocumented.  However, TxDOT's Freeway Signing Handbook, which was developed largely as a model of good signing practice and is not meant to be completely specific to Texas conditions, spells out a unit system for measuring sign message loading which is designed to be more comprehensive than the MUTCD's sketchy guidance (which relies largely on limits on numbers of destinations on individual panels and across a gantry).  Each arrow, cardinal direction word, and discrete destination is treated as a single unit, with (IIRC) recommended maxima of 20 units per gantry and 5-7 per sign panel.  This unit system is based on sign comprehension research which goes all the way back to a couple of papers published by T.W. Forbes in the late 1930's/early 1940's, which gave minimum letter heights and word limits for signs based on the intrinsic legibility of the sign lettering and the amount of time the driver has to read the sign while approaching it.  (I have long suspected that Forbes' research was funded by the Pennsylvania Turnpike Commission as part of an effort to develop signing for the newly opened Turnpike, but I haven't found documentation to prove this.)

Applying this unit system (or any other quantitative measure of message loading) to the signing in a given highway corridor gives an idea of whether there is enough of a "hole" to allow signing for concurrent routes of a secondary class.  If there is a determination that the "hole" is not large enough to provide continuity for the less important route on the advance guide and exit direction signing, the choices become arbitrary.  Signing can be omitted altogether, or various "Hail Mary" approaches can be pursued, such as putting the route in question on supplemental guide signs or trailblazers at exit ramps.  This is essentially what engineering judgment is about.

[J N Winkler]

US 169 in Kansas was recently rerouted, but signs for the highway were actually removed from segments that would have been unaffected by the rerouting (US 56/Shawnee Mission Parkway and Rainbow Boulevard).

In regard to this specific case, a possible motivation for removing US 169 signing is to clear the decks for elimination of city connecting link mileage in exchange for a capital improvement elsewhere.  It would have been KDOT's decision to do this because KDOT is responsible for trailblazers for state routes on city connecting links, regardless of whether maintenance responsibility in general rests with KDOT or the city.  One imagines that KDOT would first have obtained the localities' consent, or at least their acquiescence, to this change, and it may even have been documented in city council meeting minutes (or the like) on the Web.

There is a thread which explains city connecting links.

[tdindy88]

A similar example is I-465 in Indiana, which has several U.S. routes running concurrently along much of its length, unsigned.  The difference, though, is that, at least from the images I have seen, it appears possible to follow these U.S. routes by signs (correct me if there are junctions where this is not true), although one would not know if he or she were joining a U.S. route in the middle of its multiplex with I-465, and I don't remember there being any reassurance shields.  This approach seems preferable for maintaining the continuity of a U.S. route while minimizing signs.  But then, do other states, such as Colorado, actually find it preferable to have a U.S. route appear to end at an Interstate and then reappear somewhere else?

You are correct in that there is a sign from when you get on I-465 from the particular U.S. or state road that tells the motorist to what exit they need to proceed to continue on that route. Of course, few people really care whether or not there is a state or U.S. highway along 465 and the sign assemblys along the highway would look ridicioulous with all those state and U.S. shields, especially between Exits 46 and 47 where there's like eight different highways. Interestingly, Fort Wayne, which have similar situation with a couple or so U.S. highways that follow the bypass I-469, all highways are signed along the multiplex, so maybe it's just a matter of how many highways there are.

[Bickendan]

US 12 and 52 have signs that explicitly say to follow I-94 in Minnesota.

US 30 'disappears' from I-84 through the western portion of the Columbia River Gorge, presumably as Hist. US 30 takes up OR 100's alignment (officially, US 30 is still on I-84 and OR 100 is an independent route).

[SSOWorld]

Sometimes I just wish they'd not sign the US Route (I-39 and US 51)

[Ned Weasel]

As far as I am aware, no policies exist at the national level, while state-level policies vary considerably in depth and detail.  I have long suspected that the process of developing signing schemes at the state level (which is essentially what a decision to sign or not to sign a US highway in a given corridor is) relies heavily on engineering judgment, rather than formal codified policies.  I also suspect that the outcomes are often not committed to paper except possibly as memoranda restricted to internal circulation in the traffic design office.

In the case of New Mexico, for example, US 85 is not signed at all while it is in both Texas and Colorado.  I think there must have been a deliberate decision to this effect but I have never been shown a memo which says, explicitly, "Do not sign US 85 and do not make signing plans for I-25 which show US 85."

Again, I suspect the decision-making processes are largely undocumented.  However, TxDOT's Freeway Signing Handbook, which was developed largely as a model of good signing practice and is not meant to be completely specific to Texas conditions, spells out a unit system for measuring sign message loading which is designed to be more comprehensive than the MUTCD's sketchy guidance (which relies largely on limits on numbers of destinations on individual panels and across a gantry).  Each arrow, cardinal direction word, and discrete destination is treated as a single unit, with (IIRC) recommended maxima of 20 units per gantry and 5-7 per sign panel.  This unit system is based on sign comprehension research which goes all the way back to a couple of papers published by T.W. Forbes in the late 1930's/early 1940's, which gave minimum letter heights and word limits for signs based on the intrinsic legibility of the sign lettering and the amount of time the driver has to read the sign while approaching it.  (I have long suspected that Forbes' research was funded by the Pennsylvania Turnpike Commission as part of an effort to develop signing for the newly opened Turnpike, but I haven't found documentation to prove this.)

Applying this unit system (or any other quantitative measure of message loading) to the signing in a given highway corridor gives an idea of whether there is enough of a "hole" to allow signing for concurrent routes of a secondary class.  If there is a determination that the "hole" is not large enough to provide continuity for the less important route on the advance guide and exit direction signing, the choices become arbitrary.  Signing can be omitted altogether, or various "Hail Mary" approaches can be pursued, such as putting the route in question on supplemental guide signs or trailblazers at exit ramps.  This is essentially what engineering judgment is about.

That makes sense that such signing decisions would be made on a case-by-case basis.  Thank you for the insight.

[Kacie Jane]

If I recall correctly, Washington's Interstate/US multiplexes are usually perfectly signed with reassurance markers (i.e. an I-5 reassurance marker is always accompanied by a US 12 one), but pull-throughs and signs on intersecting roads generally only have the interstate shield.

[xonhulu]

US 12 and 52 have signs that explicitly say to follow I-94 in Minnesota.

I've seen this in other places, too.  I think Utah does this for US 50 when it merges with I-70, but they actually cosign them for several miles before the 50 shields disappear.

US 30 'disappears' from I-84 through the western portion of the Columbia River Gorge, presumably as Hist. US 30 takes up OR 100's alignment (officially, US 30 is still on I-84 and OR 100 is an independent route).

I'm not sure this was intentional.  There are still plenty of dual references to 30/84 left through there, and the stand-alone 84 shields are of more recent vintage, leading me to think leaving 30 off the assemblies was just an oversight.  However, I think that 30 should be signed on the historic highway instead of along the freeway, so I'd be pleased if your theory was accurate.

[mightyace]

There's also the short duplex of US 31 with I-65 from Exit 1 in Tennessee to Exit 354 in Alabama.

It is clear on each end that you are supposed to get on I-65 to stay on US 31 and each end tells you to get off at the correct place.  However, I don't recall seeing any US 31 signs on the I-65 mainline where they are duplexed.

[rickmastfan67]

If I recall correctly, Washington's Interstate/US multiplexes are usually perfectly signed with reassurance markers (i.e. an I-5 reassurance marker is always accompanied by a US 12 one), but pull-throughs and signs on intersecting roads generally only have the interstate shield.

They do the same thing here in Pittsburgh along I-376, US-22, US-30.  All the signage on I-79 mentions just I-376 (previously I-279 North, and US-22/US-30 West).  But when you're on the Parkway, US-22 and US-30 are co-signed with I-376 reassurance shields.

[US71]

In Arkansas, this is intentional.

US 71 and US 62 follow I-540 in NW Arkansas, but neither is posted.

US 65 follows I-40 from Conway to North Little Rock, but is not posted independently: only on BGS's approaching the split.

I forget what their reasoning is. I think Jeremy Lance may have spoken to AHTD about this once, so I'll see if he remembers.


*UPDATE*  AHTD says it's to "avoid confusion" 

[corco]

If I recall correctly, Washington's Interstate/US multiplexes are usually perfectly signed with reassurance markers (i.e. an I-5 reassurance marker is always accompanied by a US 12 one), but pull-throughs and signs on intersecting roads generally only have the interstate shield.

Except on I-90/US-2/US-395. It gets a bit sketchy there.

For US-2 east there is one sign that says it follows I-90 when you merge from 2 east to I-90 east but nothing on the mainline


and then 395 is referenced northbound at the approach (marked as east)


then marked after the SR 261 interchange (but not on the reassurance marker after the 90/395 merge)


and that's it.

For 2 west/395 south I thought there was a sign on I-90 west that said "2 W and 395 S follow I-90" but I can't find my photo of it and I can't find it on SRWeb, so maybe I dreamt it. In my dream it was mounted on an overpass.

[J N Winkler]

For 2 west/395 south I thought there was a sign on I-90 west that said "2 W and 395 S follow I-90" but I can't find my photo of it and I can't find it on SRWeb, so maybe I dreamt it. In my dream it was mounted on an overpass.

Did it have fresh sheeting?  If it did, then I suspect I have the sign design sheet for it.  (1500 sheets to go through for Washington state, though . . .)

[Rover_0]

Well, I emailed this worker at UDOT concerning the I-70/US-6/50/191 quad-plex and he guessed that, at least in that case, only the most major route (I-70) is signed to avoid "Information Overload."

Still, that doesn't explain why we see US-189 "ending" at Heber City.  Nor does it explain why we don't see US-50 on its short duplex with I-15*, or why US-89 dissapears and reappears on I-15 along the Wasatch Front.


*Though you at least have signs pointing westbound US-50 drivers to use I-15 south at Scipio, (north/east end of duplex), though US-50 signs aren't posted on I-15 itself nor are there US-50 signs at Holden (south/west end of the duplex).  That might be something I can email UDOT about, as well.

[codyg1985]

There is also US 74 whose western terminus is at the I-24/75 interchange in Chattanooga, but there is no mention of it until Cleveland, TN, and even then it is spotty until you pass through the Ocoee River Gorge as US 64 is the main route. I wonder of US 74 was intended on being extended west but never occured?

[corco]

For 2 west/395 south I thought there was a sign on I-90 west that said "2 W and 395 S follow I-90" but I can't find my photo of it and I can't find it on SRWeb, so maybe I dreamt it. In my dream it was mounted on an overpass.

Did it have fresh sheeting?  If it did, then I suspect I have the sign design sheet for it.  (1500 sheets to go through for Washington state, though . . .)

It's been two years since I would have driven by it and at that point it didn't look brand new but it wasn't particularly old, either. I'd guess 5-15 years old

[J N Winkler]

It's been two years since I would have driven by it and at that point it didn't look brand new but it wasn't particularly old, either. I'd guess 5-15 years old

Thanks for this--I'm afraid this one would be a long shot because my WSDOT archive goes back only to 2003.  I did have a quick look and found a Class A sign (which is what WSDOT calls its designable orange-background construction signs) advising traffic for US 2 and US 395 (directions given) to use Exit 282.

[NE2]

It's at the Arthur Street overpass (though not quite mounted on it): http://maps.google.com/maps?ll=47.652279,-117.395074&spn=0.012518,0.041199&t=k&z=16&layer=c&cbll=47.652068,-117.39504&panoid=JtX1c69O4bCCiiZNVT7Btg&cbp=12,282.17,,0,-4.41

[Ned Weasel]

Well, I emailed this worker at UDOT concerning the I-70/US-6/50/191 quad-plex and he guessed that, at least in that case, only the most major route (I-70) is signed to avoid "Information Overload."

Still, that doesn't explain why we see US-189 "ending" at Heber City.  Nor does it explain why we don't see US-50 on its short duplex with I-15*, or why US-89 dissapears and reappears on I-15 along the Wasatch Front.


*Though you at least have signs pointing westbound US-50 drivers to use I-15 south at Scipio, (north/east end of duplex), though US-50 signs aren't posted on I-15 itself nor are there US-50 signs at Holden (south/west end of the duplex).  That might be something I can email UDOT about, as well.

I suspected avoiding "information overload" or "sign clutter" was the rationale in most cases.  Still, it seems like it usually would be feasible to use a supplementary guide sign, such as "US XX Follow I-XX" or just a shield with an arrow, as in the cases in Minnesota and Indiana that were mentioned previously, but that's just my preference.

From looking at interchanges on I-70 in Utah on Google Maps and Street View, it seems that US 50 is usually signed, while US 6 disappears when it turns onto I-70.

Also, from what I've read recently, US 66 apparently had unsigned segments after the Interstates were in place and before it was decommissioned.  It's described in the 1995 edition of the book Main Street to Miracle Mile by Chester H. Liebs, where he says that some of its identification markers had been removed by 1980.  US 66 was decommissioned one year after I was born, so I wouldn't know about it first-hand.

[Rover_0]

If they put one of these at the Holden end of the I-15/US-50 duplex, I'd take it as a consolation to having US-50 fully signed on I-15:

I-15/US-50 Sign at Scipio

Contrast with the Holden end:

Just I-15 at Holden

[xonhulu]

Well, I emailed this worker at UDOT concerning the I-70/US-6/50/191 quad-plex and he guessed that, at least in that case, only the most major route (I-70) is signed to avoid "Information Overload."

It's not on the I-70 mainline, but they at least acknowledge the US Routes on the business loop in Green River:



On the west end of town, though, 50 gets no love:

[Rover_0]

Well, I emailed this worker at UDOT concerning the I-70/US-6/50/191 quad-plex and he guessed that, at least in that case, only the most major route (I-70) is signed to avoid "Information Overload."

It's not on the I-70 mainline, but they at least acknowledge the US Routes on the business loop in Green River:

On second thought, I do remember that one, but I think he was referring to the mainline.  Nevertheless, there is progress being made to appropriately sign all routes on multiplexes in Utah...albeit slowly.

[xonhulu]

I'd still like to see US 50 take over UT 24 through Capitol Reef NP, eliminating most of its duplex with I-70 in Utah.

[agentsteel53]

I'd still like to see US 50 take over UT 24 through Capitol Reef NP, eliminating most of its duplex with I-70 in Utah.

how would you route it back to the 50 alignment which heads west past Salina?

I'd always thought UT-24 would've made a sensible US-24 extension - maybe somehow find an alternate alignment to avoid a long 6/50/24 multiplex