NY - Sequential vs. Mile Based Exits

[MikeSantNY78]

The funny thing is that when there was an upswell to switch over at NYSDOT some years ago, a rather...singularly intelligent... office director suggested NEW EXIT XX signage, I kid you not.

I remember hearing that and discussing it with some folks I know in NYSDOT. Wasn't that plan to post NEW EXIT XX for like 5 years and then switch them around and post FORMERLY EXIT XX for the next five or something like that?

Heck, why not just name the interchanges instead of numbering them? Seems like it would be a lot easier to keep the designations unique, and it probably matches more closely the way we actually navigate these days.


iPhone

Like in California, before they retro-fitted the BGSs to include exit numbers a few years back?

[roadman]

I believe I've read that RI experimented with dual posting.  No idea why it was ended.

The dual posting "MILE XX  EXIT YY" option was included as a "may" condition in the 1971 MUTCD.  The idea was to provide improved guidance to unfamiliar drivers in states that used sequential exit numbering.  It was subsequently removed from the 1978 MUTCD.  My guess is that somebody determined that the extra legend didn't necessarily improve navigation for drivers, and added to message clutter on BGS panels.

"MILE XX EXIT YY' tabs were included on the BGS panels installed on I-93 between Somerville and Methuen during the roadway upgrade projects in the mid-1970s.  These signs lasted until the panel replacement projects in 1991 and 1992.

As to the whole "sequential versus reference post" debate, it's interesting to note that the 1971 MUTCD refers to the desire to get states to convert to reference point numbering as an AASHO (now AASHTO) initiative.  It's equally interesting that neither the 1978 nor 1988 editions of the MUTCD make any reference to "sequential vs. reference post", and that the language allowing either as an option - but emphasizing that reference post based numbering was preferred - did not appear until the 2000 MUTCD and was repeated in the 2003 MUTCD.

[J N Winkler]

I-40 in TN is 4 miles longer than originally planned because of Overton Park.  The exit numbers were not adjusted.

I've looked at the area in Google Maps and it appears the difference is finessed by using "long miles" along the I-240 routing that was adopted when the plan to build through Overton Park was abandoned.  E.g., Exits 8A-8B (SR 14 Austin Peay Highway) is 10 miles from the Arkansas state line, while Exit 16 (SSR 177 Germantown) is 20 miles from the Arkansas state line.  I wonder how the "long miles" work now that TennDOT has ARTIMIS-style enhanced location reference markers with nominal spacing of 0.2 mile.  Progression seems normal, so I suspect each marker represents one-fifth of a "long mile" rather than a true statute mile.

I believe I've read that RI experimented with dual posting.  No idea why it was ended.

Wikipedia has a photo.  Colorado's format was similar.

The dual posting "MILE XX  EXIT YY" option was included as a "may" condition in the 1971 MUTCD.  The idea was to provide improved guidance to unfamiliar drivers in states that used sequential exit numbering.  It was subsequently removed from the 1978 MUTCD.  My guess is that somebody determined that the extra legend didn't necessarily improve navigation for drivers, and added to message clutter on BGS panels.

Did FHWA provide any encouragement to agencies to dual-post other than explicitly describing it as an option in the MUTCD?  (I feel a TRIS search coming on, to see if the effectiveness was actually studied before the option was withdrawn in the 1978 MUTCD.)

[empirestate]

So yeah, I had every of intention of being persuaded, if possible, until a page or so ago.

Is the timing a coincidence? I think not

Coincident to what?

[webny99]

So yeah, I had every of intention of being persuaded, if possible, until a page or so ago.

Is the timing a coincidence? I think not

Coincident to what?

Coincident to me finally finding a way to express my point, in such a way that listening to reason or being stubborn were the only options you had 



To add to the above discussion, is there anyone here who is actually in favor of dual posting? Using multiple systems, it seems to me, would cause unnecessary sign clutter, and potentially confuse motorists as they try to take in high volumes of information, not all of which is strictly necessary.

[empirestate]

So yeah, I had every of intention of being persuaded, if possible, until a page or so ago.

Is the timing a coincidence? I think not

Coincident to what?

Coincident to me finally finding a way to express my point, in such a way that listening to reason or being stubborn were the only options you had 

Oh!–no; sorry.

(Which were you thinking of, the typewriter thing?)

[vdeane]

I-690 was completely renumbered from sequential to sequential back when the new interchange with the Thruway was built, 1988 or so?  I think the numbers shifted by 5 and the interchange with I-81 still did not receive a number at that time. You can see the overlays on the folded up signs used during the State Fair.

Can't believe I totally forgot about I-690! 

I've looked at the area in Google Maps and it appears the difference is finessed by using "long miles" along the I-240 routing that was adopted when the plan to build through Overton Park was abandoned.  E.g., Exits 8A-8B (SR 14 Austin Peay Highway) is 10 miles from the Arkansas state line, while Exit 16 (SSR 177 Germantown) is 20 miles from the Arkansas state line.  I wonder how the "long miles" work now that TennDOT has ARTIMIS-style enhanced location reference markers with nominal spacing of 0.2 mile.  Progression seems normal, so I suspect each marker represents one-fifth of a "long mile" rather than a true statute mile.

Looks to me like they're just using I-240 numbers/mileage for the rerouted portion and the planned mileage/numbers for everything else.  Note that the I-240/I-40 interchange is either exit 10 or exit 12 depending on which direction you go, with both 10 and 12 repeating with adjacent interchanges.

[PurdueBill]

Didn't they use "A" milemarkers on I-40 in Memphis to fudge things?  (e.g., Mile 1, Mile 1A, Mile 2...)  I could swear I saw at least a couple of those once.

Edit: Found it....I kinda remembered.  There is 1, 1A, 1B, then 2 for milemarkers.  I can't remember if there are other lettered ones but it would take looking around online--been too long since seeing in person to remember well.

[vdeane]

Looks like they use the suffixed miles to differentiate between the parts that use I-40 and I-240 mileage.  The exit numbers are interesting as the adjacent numbers are suffixed at the I-40/I-240/Sam Cooper Blvd interchange but the adjacent duplicates are not, and some of the I-240 ramps aren't accessible from I-40 anyways.  Someone just traveling through might never notice that the exit numbers jump around, unless they go both ways and pay enough attention to notice that the interchange is exit 10 WB but exit 12 EB.

[TML]

The main reason why NY has not switched to distance-based exit numbers is because they tried doing this with highways in NYC and Schenectady, where the scheme didn't work well because many exits were spaced very close together. According to the NY DOT website, they do not plan to implement this system statewide until (1) the federal government makes it mandatory, or (2) spare funding is available.

As a compromise, I could accept a system where exit numbers in major urban areas retain the sequential system (at least temporarily) while those in rural areas get changed to distance-based numbers. For example, I'd much rather see "Exit 495" for the Interstate 90 interchange at Ripley instead of "Exit 61."

[vdeane]

From what I understand, there was a plan to convert in the 70s, but at the time, the US was slated to go metric within 10 years, so it wasn't considered practical to switch only to have to change the numbers again.

NYSDOT (there is no NYDOT) didn't really give up on metric conversion until well after Reagan killed it, and then you have Rothman's story of managers trying to make conversion as expensive as possible.

(personal opinion)

[seicer]

spare funding is available.

That's a riot, considering how much money was spent installing and then defending the Cuomo signs - and how much they could stand to lose if the state doesn't comply with the MUTCD.

[Brandon]

If exits are closely spaced, that's what letter suffixes are for.  As an example, I-90/94 (Kennedy Expressway) in Chicago has exits 51a through 51i.

[Rothman]

The idea that the Sheridan and I-890 were used as experiments goes back to a memo that NYSDOT used to rely upon to deflect people who wanted mileage-based numbering.  I even shared it with the Yahoo group once a long time ago.

To accept this party line is rather ridiculous, though.  The real opposition is in the fact NYSDOT would rather spend its money on other things and from businesses worried about advertising changes.

FHWA doesn't seem to be that forceful about the conversion, either.  Until they take action, either through penalties or allocating money for it, NYSDOT probably won't on its own.

[SignBridge]

Mileage based exit numbering already is mandatory in the MUTCD. The FHWA just hasn't been aggressively enforcing it. Sec. 2E-31, Par.4 reads: Exit numbering shall use the reference location sign exit numbering method. The consecutive exit numbering method shall not be used. That's all folks!

[02 Park Ave]

Pennsylvania changed over from sequential to mile-based exit numbering around 15 years ago.  If it wasn't a big deal for them then, then why is it now for New York State?  Is the hold-up with NYSDOT or with the Thruway Authority?

[kalvado]

Mileage based exit numbering already is mandatory in the MUTCD. The FHWA just hasn't been aggressively enforcing it. Sec. 2E-31, Par.4 reads: Exit numbering shall use the reference location sign exit numbering method. The consecutive exit numbering method shall not be used. That's all folks!

OK, OK, send us another neck breaking $150,234 fine and lets move on.

[empirestate]

Pennsylvania changed over from sequential to mile-based exit numbering around 15 years ago.  If it wasn't a big deal for them then, then why is it now for New York State?

It isn't; that's the whole point. It's a very non-important issue.

[Roadwarriors79]

If/when NY renumbers their exits, will I-90 use its own set of numbers, or will it use numbers that follow the Thruway mileage?

[webny99]

Pennsylvania changed over from sequential to mile-based exit numbering around 15 years ago.  If it wasn't a big deal for them then, then why is it now for New York State?

It isn't; that's the whole point. It's a very non-important issue.

And the whole reason this thread exists is because it is important to some of us, regardless of the importance (or lack thereof) on a macro- scale. As mentioned over on the off-topic board, it seems that some important figures in NY have an irrational fear of mileage-based exits 

If/when NY renumbers their exits, will I-90 use its own set of numbers, or will it use numbers that follow the Thruway mileage?

This, too, has been a frequent subject of discussion on the forum. In large part, this is because there is no known (or predicted) answer. Hence

The possible conversion of the Thruway to AET is among the many variables at play here. Needless to say, I'd much prefer the former, which would become the more likely scenario with AET.

[02 Park Ave]

Is Governor Cuomo aware of this problem?

[seicer]

I'm sure he has bigger issues to worry about than mileage based exits (as much as I am a proponent of them).

[SignBridge]

Governor Cuomo obviously doesn't care what the FHWA or the MUTCD says. He does whatever he wants as in the blue advertising signs. He's in his own little world as are most politicians.

[jp the roadgeek]

If/when NY renumbers their exits, will I-90 use its own set of numbers, or will it use numbers that follow the Thruway mileage?

Remains to be seen if the Thruway exits would be numbered on internal mileage (from the NYC line) or individual highways.  Free 90 would go with I-90 mileage (348-368), but another question is would the Berkshire Spur exits be based on I-90 mileage or spur mileage? Big difference if B3 became Exit 23 or Exit 385.

[Alps]

If/when NY renumbers their exits, will I-90 use its own set of numbers, or will it use numbers that follow the Thruway mileage?

Remains to be seen if the Thruway exits would be numbered on internal mileage (from the NYC line) or individual highways.  Free 90 would go with I-90 mileage (348-368), but another question is would the Berkshire Spur exits be based on I-90 mileage or spur mileage? Big difference if B3 became Exit 23 or Exit 385.

I imagine if NY ever renumbers it's because its hand has been forced by FHWA, so in that case numbering would follow the Interstate highway the entire way.