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National Boards => General Highway Talk => Topic started by: SoCal Kid on April 08, 2019, 02:05:15 PM

Title: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: SoCal Kid on April 08, 2019, 02:05:15 PM
"In the case of an auxiliary Interstate highway which has both ends at Interstates but not the same Interstate, some states treat these as bypasses while others treat these as spurs." - Wikipedia.

This is kinda debatable. In California, I-205 connects I-580 and I-5. It is numbered like a bypass. I-505 connects I-5 with I-80, it is numbered like a spur.

Should it be these types of auxiliary Interstates be numbered like spurs or as bypasses?
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Hurricane Rex on April 08, 2019, 02:09:46 PM
I'll list it like priorities

1. What numbers are available? If only one type, use that.

2. If both are, use spur numbers as they do not re-connect back to the parent interstate.

SM-J737T

Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: SoCal Kid on April 08, 2019, 02:11:32 PM
I see
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Beltway on April 08, 2019, 02:11:50 PM
Almost half of the odd-digit prefix auxiliary Interstate routes are both -- they connect to 2 or more other Interstate routes, and they extend further to a terminus at a non-Interstate route.

A few examples -- NJ I-195, CA I-110, FL I-595
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Brandon on April 08, 2019, 04:15:42 PM
Some states do it one way, some do it another.

For example, Illinois tends to use an odd number, even if the child route connects to other interstates, leaving the even numbers for those that return to their parent interstate.

I-155: connects I-55 with I-74.
I-255: meets I-55 in Missouri and in Collinsville, but goes past I-55 to I-270.  The one current exception.
I-355: connects I-55 to I-80, I-88, and I-290.
I-270: meets I-70 in Missouri and Troy.
I-172: spur off I-72 to Quincy.
I-474: bypass of Peoria, meets I-74 at both ends.
I-180: spur off I-80 to Hennepin.
I-280: meets I-80 in Iowa and Coal Valley.  Concurrent with I-74 to meet I-80.
I-190: spur off I-90 into O'Hare International Airport.
I-290: meets I-90 at both ends.
I-294: bypass of Chicago, meets I-94 at both ends.  Concurrent with I-80 to meet I-94.

Even seems to apply to the state route "interstates".
IL-390: meets I-290 in the middle, will meet I-490 at the east end, spur toward Elgin at the west end.
IL-394: spur south from I-94 toward Crete and Beecher.

I-490 will be another exception to this, meeting I-90 at the north end, I-294 at the south end, and IL-390 in the middle.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: bzakharin on April 08, 2019, 04:40:13 PM
I feel like routs such as I-276 (in PA) and I-280 (in NJ) are correctly numbered in spirit, as they both end at the same route as they end at the same corridor as their parent (more so for 280).
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: TEG24601 on April 08, 2019, 06:51:49 PM
It really shouldn't matter.  Even numbers would be preferred, but odds allowed, but only after an even option from both Interstates are exhausted.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: SoCal Kid on April 08, 2019, 07:20:38 PM
Quote from: TEG24601 on April 08, 2019, 06:51:49 PM
It really shouldn't matter.  Even numbers would be preferred, but odds allowed, but only after an even option from both Interstates are exhausted.
I know, but I'm just curious about what others think
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Eth on April 08, 2019, 07:57:12 PM
An even number feels more natural to me, though that's probably just because it's what I'm used to – here in Georgia, 675 is the only one that does this, and I also lived for a while in Maryland, where 270 is the only one that does this.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: SoCal Kid on April 08, 2019, 08:00:28 PM
Quote from: Eth on April 08, 2019, 07:57:12 PM
An even number feels more natural to me, though that's probably just because it's what I'm used to – here in Georgia, 675 is the only one that does this, and I also lived for a while in Maryland, where 270 is the only one that does this.
I also favor even numbers. Because those types of auxiliary Interstates connect two Interstates like bypasses, while spurs (odd numbers) just connect an Interstate to a district or city (aka its terminus is a usually a road or non-Interstate).
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: kphoger on April 08, 2019, 08:59:07 PM
+1 here for even numbers.

IMO, odd numbers should be reserved for Interstates that basically end somewhere.

OTOH, I would also be in favor of eliminating any distinction between odd and even, and also eliminating parent- child-highway numering...
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hbelkins on April 08, 2019, 09:15:16 PM
Quote from: SoCal Kid on April 08, 2019, 02:05:15 PM
Wikipedia

That's your first mistake right there.  :bigass:
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: SoCal Kid on April 08, 2019, 09:19:28 PM
Quote from: hbelkins on April 08, 2019, 09:15:16 PM
Quote from: SoCal Kid on April 08, 2019, 02:05:15 PM
Wikipedia

That's your first mistake right there.  :bigass:
?
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hotdogPi on April 08, 2019, 09:22:27 PM
Quote from: SoCal Kid on April 08, 2019, 09:19:28 PM
Quote from: hbelkins on April 08, 2019, 09:15:16 PM
Quote from: SoCal Kid on April 08, 2019, 02:05:15 PM
Wikipedia

That's your first mistake right there.  :bigass:
?

Wikipedia articles on roads are pretty accurate. There are no issues with POV pushing or living person biographies, and vandalism is relatively rare compared to more popular and more controversial articles.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: SoCal Kid on April 08, 2019, 09:24:53 PM
Quote from: 1 on April 08, 2019, 09:22:27 PM
Quote from: SoCal Kid on April 08, 2019, 09:19:28 PM
Quote from: hbelkins on April 08, 2019, 09:15:16 PM
Quote from: SoCal Kid on April 08, 2019, 02:05:15 PM
Wikipedia

That's your first mistake right there.  :bigass:
?

Wikipedia articles on roads are pretty accurate. There are no issues with POV pushing or living person biographies, and vandalism is relatively rare compared to more popular and more controversial articles.
^^^
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: sprjus4 on April 08, 2019, 09:54:38 PM
As for crossing the parent route twice but continuing beyond it to terminate at another destination...

Interstate 264 in Hampton Roads, Virginia stretches from I-64 at Bowers Hill in Chesapeake, through Downtown Norfolk where it meets I-464, then meets back up with I-64 east of Downtown. But then it keeps going east until terminating at the Virginia Beach Oceanfront.

Interstate 295 in the Richmond area is similar, where it branches off I-95 south of Petersburg, crosses I-64 east of Richmond, meets back with I-95 north of Richmond, but then continues west to finally terminate at I-64 west of Richmond.


As for branching off one interstate and linking up to another interstate...

Interstate 285 (even-numbered) connects Interstate 85 at Lexington, North Carolina to Interstate 40 in Winston-Salem, North Carolina. It branches off I-85 once, and never meets back, though connects to another interstate.

Interstate 274 (proposed, not official, so could change) (even-numbered) would connect Interstate 74 (currently under construction) north of Winston-Salem to Interstate 40 west of Winston-Salem.

The short-lived Interstate 495 (even-numbered) was planned to connect I-40 at Raleigh, North Carolina to I-95 at Rocky Mount, North Carolina. This designation, however, has been deleted and replaced with Interstate 87, which would extend the I-495 routing all the way to Hampton Roads, Virginia via Elizabeth City. But the point still stands... it was an even numbered designation planned to link two different interstates.

On the contrary, Interstate 795 (odd-numbered), when completed, will connect Interstate 95 at Wilson, North Carolina to Interstate 40 at Faison, North Carolina.

Interstate 587 connects Interstate 87 at Zebulon, North Carolina to Interstate 95 at Wilson, North Carolina, though does continue east until terminating at Greensville, North Carolina at a non-interstate.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: sparker on April 08, 2019, 11:08:20 PM
CA's 3di's are odd ducks indeed; only 3 (215, 405, 805) intersect their parent twice, 1 even 2di (605) intersects its parent in the middle.  The remainder, whether odd or even prefix, are a mix of parental single intersects or even branches of other 3di's (105, 380, 980).  And to top it off, we've got one (580) that multiplexes with its parent for a bit.  And, of course, the Voldemort of Interstates -- the number that shall not be repeated  -- hint -- it's an orphan (parentless) and is the other Interstate (besides 980) connecting 580 and 880; the only reason for its existence is as a truck-route alternative to I-580, which forbids them (east of downtown) in Oakland.   Blame topology, bodies of water, and, of course, politics for these configurations.     
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: SoCal Kid on April 08, 2019, 11:13:28 PM
Quote from: sparker on April 08, 2019, 11:08:20 PM
CA's 3di's are odd ducks indeed; only 3 (215, 405, 805) intersect their parent twice, 1 even 2di (605) intersects its parent in the middle.  The remainder, whether odd or even prefix, are a mix of parental single intersects or even branches of other 3di's (105, 380, 980).  And to top it off, we've got one (580) that multiplexes with its parent for a bit.  And, of course, the Voldemort of Interstates -- the number that shall not be repeated  -- hint -- it's an orphan (parentless) and is the other Interstate (besides 980) connecting 580 and 880; the only reason for its existence is as a truck-route alternative to I-580, which forbids them (east of downtown) in Oakland.   Blame topology, bodies of water, and, of course, politics for these configurations.     
I-238
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: skluth on April 09, 2019, 01:10:37 AM
I don't care if they're numbered as even or odd 3DIs. As long as they're not labeled 2DIs like I-12 or I-97.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: epzik8 on April 09, 2019, 02:29:54 PM
I don't think so.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hotdogPi on April 09, 2019, 02:36:40 PM
Loops/beltways should be even even if only one end is at the parent (e.g. both I-291s, I-290 MA as it forms two "legs", I-495 MA), while anything taking nearly a straight line that goes into a large city instead of around should be odd (e.g. I-195 MA/RI, I-395 MA/CT).
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Ben114 on April 09, 2019, 04:24:00 PM
Quote from: 1 on April 09, 2019, 02:36:40 PM
Loops/beltways should be even even if only one end is at the parent (e.g. both I-291s, I-290 MA as it forms two "legs", I-495 MA), while anything taking nearly a straight line that goes into a large city instead of around should be odd (e.g. I-195 MA/RI, I-395 MA/CT).
It should be distance based.
I-291 in MA ends at I-90 fairly close to I-91
I-290 in MA ends at I-495 fairly close to I-90
I-395 in MA ends far from I-95 so it should be odd
I-495 in MA meets with I-95 multiple times so it should be even
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: sparker on April 09, 2019, 05:11:36 PM
Quote from: SoCal Kid on April 08, 2019, 11:13:28 PM
Quote from: sparker on April 08, 2019, 11:08:20 PM
CA's 3di's are odd ducks indeed; only 3 (215, 405, 805) intersect their parent twice, 1 even 2di (605) intersects its parent in the middle.  The remainder, whether odd or even prefix, are a mix of parental single intersects or even branches of other 3di's (105, 380, 980).  And to top it off, we've got one (580) that multiplexes with its parent for a bit.  And, of course, the Voldemort of Interstates -- the number that shall not be repeated  -- hint -- it's an orphan (parentless) and is the other Interstate (besides 980) connecting 580 and 880; the only reason for its existence is as a truck-route alternative to I-580, which forbids them (east of downtown) in Oakland.   Blame topology, bodies of water, and, of course, politics for these configurations.     
I-238

Bingo -- as Californians, we all share in the shame!
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Beltway on April 09, 2019, 05:16:18 PM
Quote from: skluth on April 09, 2019, 01:10:37 AM
I don't care if they're numbered as even or odd 3DIs. As long as they're not labeled 2DIs like I-12 or I-97.

What should I-12 be?  At 87 miles long it would fit into the typical realm of intra-state Interstate routes.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Ben114 on April 09, 2019, 05:41:51 PM
Quote from: Beltway on April 09, 2019, 05:16:18 PM
Quote from: skluth on April 09, 2019, 01:10:37 AM
I don't care if they're numbered as even or odd 3DIs. As long as they're not labeled 2DIs like I-12 or I-97.

What should I-12 be?  At 87 miles long it would fit into the typical realm of intra-state Interstate routes.

The only free number is currently I-810.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hbelkins on April 09, 2019, 07:30:06 PM
Quote from: Beltway on April 09, 2019, 05:16:18 PM
Quote from: skluth on April 09, 2019, 01:10:37 AM
I don't care if they're numbered as even or odd 3DIs. As long as they're not labeled 2DIs like I-12 or I-97.

What should I-12 be?

I-10. The loop into NO should be I-6.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Darkchylde on April 09, 2019, 09:43:17 PM
Quote from: Beltway on April 09, 2019, 05:16:18 PM
Quote from: skluth on April 09, 2019, 01:10:37 AM
I don't care if they're numbered as even or odd 3DIs. As long as they're not labeled 2DIs like I-12 or I-97.

What should I-12 be?  At 87 miles long it would fit into the typical realm of intra-state Interstate routes.
I-10N.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Ned Weasel on April 09, 2019, 10:39:17 PM
There is so much inconsistency and illogic to the way highways are numbered that I've given up on trying to believe that there is an intelligent set of guiding principles to their numbering.  Never mind the problems with US and state highway numbering; let's just look at the (mostly relevant) issues with Interstate highway numbering:


Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: TheStranger on April 09, 2019, 11:08:37 PM
Quote from: stridentweasel on April 09, 2019, 10:39:17 PM
There is so much inconsistency and illogic to the way highways are numbered that I've given up on trying to believe that there is an intelligent set of guiding principles to their numbering.  Never mind the problems with US and state highway numbering; let's just look at the (mostly relevant) issues with Interstate highway numbering:


  • Personally, I would prefer 3DIs where both ends are at an Interstate to begin with an even number, even if it terminates at two different Interstates, except when all the even numbers are taken.  Examples of my preferred method are Interstates 276 and 476 in Pennsylvania, 255 and 270 in MO and IL, and 235 and 635 in KS (and MO in 635's case).
  • Examples of doing it the other way are Interstate 376 in Pennsylvania, I-170 in MO (yet people care that 370 doesn't start with an even number?), and 135 and 335 in KS.
  • Now what about all those 2DIs that follow an unnecessarily inefficient route?  I'm mostly looking at I-10 in New Orleans and I-90 in Albany.  At least Pennsylvania had the good sense not to route I-76 off of the Turnpike and through Pittsburgh.
  • What about every 2DI that's shorter than I-476 or I-135?
  • What about those pairs of 3DIs that effectively form a single route?  I'm talking about I-494 and 694 in Minnesota, and I-275 and 696 in Michigan.
  • What's the deal with I-41?  This could have easily been a northern extension of I-57, but it just had to have its own number!  And now they're proposing a southern extension of I-57?
  • Having different 2DI segments with the same number is understandable when we're talking about routes that are in vastly different geographic regions.  But then along came I-49, 69, 73, and 74 to mess that up!
  • Lettered suffixes were okay at first.  But then they weren't, unless they were in the Twin Cities or the DFW area.  And now they are again, because somehow I-69 is really important!
  • I-99 and I-238 should officially compete for a green sign reading "Dead Horse Memorial Highway."


- I-76 once did go into Pittsburgh if I'm not mistaken (though pretty much all of the former I-80S from Ohio east is now I-76).  If we are to go by "efficency" only, then should I-75 even go into Detroit instead of just simply following US 23 between Toledo and Flint?

- 275/696 aren't really one corridor at all, even though they share a common terminus at I-96.  494/694 has a bit of a rectangular/oval configuration not unlike I-280/680 in the San Francisco Bay Area so I can see why there are separate numbers for each half.

- 49 and 69 are supposed to eventually have all their segments connected. 
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: kendancy66 on April 09, 2019, 11:21:31 PM
Quote from: sprjus4 on April 08, 2019, 09:54:38 PM
As for crossing the parent route twice but continuing beyond it to terminate at another destination...

Interstate 264 in Hampton Roads, Virginia stretches from I-64 at Bowers Hill in Chesapeake, through Downtown Norfolk where it meets I-464, then meets back up with I-64 east of Downtown. But then it keeps going east until terminating at the Virginia Beach Oceanfront.

Interstate 295 in the Richmond area is similar, where it branches off I-95 south of Petersburg, crosses I-64 east of Richmond, meets back with I-95 north of Richmond, but then continues west to finally terminate at I-64 west of Richmond.


As for branching off one interstate and linking up to another interstate...

Interstate 285 (even-numbered) connects Interstate 85 at Lexington, North Carolina to Interstate 40 in Winston-Salem, North Carolina. It branches off I-85 once, and never meets back, though connects to another interstate.

Interstate 274 (proposed, not official, so could change) (even-numbered) would connect Interstate 74 (currently under construction) north of Winston-Salem to Interstate 40 west of Winston-Salem.

The short-lived Interstate 495 (even-numbered) was planned to connect I-40 at Raleigh, North Carolina to I-95 at Rocky Mount, North Carolina. This designation, however, has been deleted and replaced with Interstate 87, which would extend the I-495 routing all the way to Hampton Roads, Virginia via Elizabeth City. But the point still stands... it was an even numbered designation planned to link two different interstates.

On the contrary, Interstate 795 (odd-numbered), when completed, will connect Interstate 95 at Wilson, North Carolina to Interstate 40 at Faison, North Carolina.

Interstate 587 connects Interstate 87 at Zebulon, North Carolina to Interstate 95 at Wilson, North Carolina, though does continue east until terminating at Greensville, North Carolina at a non-interstate.

The interstate 274 example should fall under the "beyond" category, it supposed to end at US-158
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: MantyMadTown on April 10, 2019, 06:32:16 PM
Quote from: stridentweasel on April 09, 2019, 10:39:17 PM

  • What's the deal with I-41?  This could have easily been a northern extension of I-57, but it just had to have its own number!  And now they're proposing a southern extension of I-57?

IDOT wanted nothing to do with making I-41 a northern extension of I-57. The same thing was also proposed when I-43 was built, but again Illinois didn't go along with it. I agree that I-41 should've been called something else, but for that to happen Illinois would've had to agree with it in the first place. And if I-41 was called I-57, then I-43 would've been east of I-57 except for the part southwest of Milwaukee, which would mostly conflict with the interstate grid. I honestly think that I-43 should've ultimately been called I-57 (with I-41 being either I-53 or a northern extension of I-55), but you can't change history, so we had to make the best of it. For Wisconsin the numbers 39, 41, and 43 make sense, but if Illinois actually went along the grid wouldn't be fucked up here like it is now.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Ben114 on April 10, 2019, 06:50:19 PM
Quote from: stridentweasel on April 09, 2019, 10:39:17 PM

  • Now what about all those 2DIs that follow an unnecessarily inefficient route?  I'm mostly looking at I-10 in New Orleans and I-90 in Albany.  At least Pennsylvania had the good sense not to route I-76 off of the Turnpike and through Pittsburgh.
I think this is mostly for travelers to only have to follow one number to get to a big city. In New Orleans, they could've just put I-10 on I-12, and renumbered the I-10 section to I-6 or I-810. Same thing happens in Massachusetts, they could have easily terminated I-93 at I-95 in Reading, and numbered the Canton-Reading portion as I-695.

I-90 takes a pretty much straight forward route through Albany.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Ned Weasel on April 10, 2019, 07:48:24 PM
Quote from: Ben114 on April 10, 2019, 06:50:19 PM
I-90 takes a pretty much straight forward route through Albany.

But unless you're going to Albany, it's more efficient to follow the New York State Thruway (unless you're adamant about shunpiking).
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: vdeane on April 10, 2019, 07:52:03 PM
Quote from: stridentweasel on April 10, 2019, 07:48:24 PM
Quote from: Ben114 on April 10, 2019, 06:50:19 PM
I-90 takes a pretty much straight forward route through Albany.

But unless you're going to Albany, it's more efficient to follow the New York State Thruway (unless you're adamant about shunpiking).
Mileage-wise it's about the same each way (actually about a mile shorter going through Albany rather than staying on the Thruway, doing a rough estimate in Google Maps).  You wouldn't even notice it if it weren't for the Thruway, the interchanges at either end of free 90, or the toll booths.  Certainly not in the same league as I-10 through New Orleans.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hobsini2 on April 20, 2019, 05:36:10 PM
Quote from: kphoger on April 08, 2019, 08:59:07 PM
+1 here for even numbers.

IMO, odd numbers should be reserved for Interstates that basically end somewhere.

OTOH, I would also be in favor of eliminating any distinction between odd and even, and also eliminating parent- child-highway numering...


So in the case of I-135 or I-335 in Kansas or I-196 in Michigan, you would have them be an even number?

I think using an odd number for these kind of routes is perfectly fine because the are connecting to other urban areas. Wichita-Salina, Emporia-Topeka, Benton Harbor/St Joseph-Holland/Muskegon but are too short to use as a single or two digit number.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: GaryV on April 21, 2019, 07:01:33 AM
Quote from: hobsini2 on April 20, 2019, 05:36:10 PM

So in the case of I-135 or I-335 in Kansas or I-196 in Michigan, you would have them be an even number?

I-196 originally was a spur - it was the portion of I-96 that goes from Grand Rapids to Muskegon.

But since what is now I-196 didn't get built for a number of years, they decided to flip the route numbers so 96 wouldn't randomly turn into 196 on the east side of GR.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Verlanka on April 21, 2019, 08:23:21 AM
Quote from: hobsini2 on April 20, 2019, 05:36:10 PM
I think using an odd number for these kind of routes is perfectly fine because the are connecting to other urban areas. Wichita-Salina, Emporia-Topeka, Benton Harbor/St Joseph-Holland/Muskegon but are too short to use as a single or two digit number.
If that's the case, then I-476 should be renumbered I-776 or I-976 (I-576 is already taken).
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hotdogPi on April 21, 2019, 08:25:41 AM
Quote from: Verlanka on April 21, 2019, 08:23:21 AM
Quote from: hobsini2 on April 20, 2019, 05:36:10 PM
I think using an odd number for these kind of routes is perfectly fine because the are connecting to other urban areas. Wichita-Salina, Emporia-Topeka, Benton Harbor/St Joseph-Holland/Muskegon but are too short to use as a single or two digit number.
If that's the case, then I-476 should be renumbered I-776 or I-976 (I-576 is already taken).

I would actually prefer 181.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: bing101 on April 21, 2019, 08:56:18 AM
Quote from: SoCal Kid on April 08, 2019, 11:13:28 PM
Quote from: sparker on April 08, 2019, 11:08:20 PM
CA's 3di's are odd ducks indeed; only 3 (215, 405, 805) intersect their parent twice, 1 even 2di (605) intersects its parent in the middle.  The remainder, whether odd or even prefix, are a mix of parental single intersects or even branches of other 3di's (105, 380, 980).  And to top it off, we've got one (580) that multiplexes with its parent for a bit.  And, of course, the Voldemort of Interstates -- the number that shall not be repeated  -- hint -- it's an orphan (parentless) and is the other Interstate (besides 980) connecting 580 and 880; the only reason for its existence is as a truck-route alternative to I-580, which forbids them (east of downtown) in Oakland.   Blame topology, bodies of water, and, of course, politics for these configurations.     
I-238




I-280 is another interstate that does not touch its parent interstate though given that its only 1/4 mile from the Bay Bridge and was originally going to connect with CA-480 though but that was cancelled though. 
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hotdogPi on April 21, 2019, 08:59:46 AM
Quote from: bing101 on April 21, 2019, 08:56:18 AM
I-280 is another interstate that does not touch its parent interstate though given that its only 1/4 mile from the Bay Bridge and was originally going to connect with CA-480 though but that was cancelled though.

If it doesn't touch any 2dis at all, nothing can be done to fix it.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: ilpt4u on April 21, 2019, 11:51:50 AM
Quote from: Verlanka on April 21, 2019, 08:23:21 AM
Quote from: hobsini2 on April 20, 2019, 05:36:10 PM
I think using an odd number for these kind of routes is perfectly fine because the are connecting to other urban areas. Wichita-Salina, Emporia-Topeka, Benton Harbor/St Joseph-Holland/Muskegon but are too short to use as a single or two digit number.
If that's the case, then I-476 should be renumbered I-776 or I-976 (I-576 is already taken).
I would just swap the 376 and 476 designations in PA
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: kphoger on April 22, 2019, 01:25:15 PM
Quote from: hobsini2 on April 20, 2019, 05:36:10 PM
Quote from: kphoger on April 08, 2019, 08:59:07 PM
+1 here for even numbers.

IMO, odd numbers should be reserved for Interstates that basically end somewhere.

OTOH, I would also be in favor of eliminating any distinction between odd and even, and also eliminating parent- child-highway numering...


So in the case of I-135 or I-335 in Kansas or I-196 in Michigan, you would have them be an even number?

I-135 shouldn't exist at all.  It should just be US-81.

I-335 should be an even 3di because it is basically serves as part of an alternate route between KS and Wichita.  Let's call it I-835.

You might have me convinced with I-196, but I could still easily go with I-896 instead.

However, as I mentioned, my actual preference (except that what I said about I-135 is still absolutely true) would be to eliminate any distinction between even and odd 3dis:  just use whatever number is available and don't worry about whether it's a loop or a spur.  And I also hate parent-child numbering.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: webny99 on April 22, 2019, 02:57:57 PM
Quote from: kphoger on April 22, 2019, 01:25:15 PM
I-135 shouldn't exist at all.  It should just be US-81.

It should actually be part of an I-35 which runs from Laredo, TX to Pembina, ND, but that's a different subject.  :-P
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: roadman on April 22, 2019, 03:45:59 PM
Quote from: 1 on April 09, 2019, 02:36:40 PM
Loops/beltways should be even even if only one end is at the parent (e.g. both I-291s, I-290 MA as it forms two "legs", I-495 MA), while anything taking nearly a straight line that goes into a large city instead of around should be odd (e.g. I-195 MA/RI, I-395 MA/CT).

I-290 was originally supposed to continue past I-495 and reconnect with I-90 in Framingham.  I-495 originally ended at I-95 in Mansfield and was later extended to I-195 in Wareham.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: PHLBOS on April 23, 2019, 03:36:28 PM
Quote from: TheStranger on April 09, 2019, 11:08:37 PM
- I-76 once did go into Pittsburgh if I'm not mistaken (though pretty much all of the former I-80S from Ohio east is now I-76).
Correct, I-76 went into Pittsburgh until 1972 when it shifted onto its current routing (replacing I-80S).  The old I-76 west of the PA Turnpike's Exit 57 (Pittsburgh interchange) became the current I-376.
_____________________________________
The issue with the current odd/even 3dis and their intended assignments/designations is that there are more odd 3di numbers (1XX, 3XX, 5XX, 7XX & 9XX) available then even 3di numbers (2XX, 4XX, 6XX & 8XX); but there are more bypasses/beltways/through-city routes (typical candidates for even 3dis) out there than there are spur routes (typical odd 3dis).

Note: not an intended plug, mind you; but given the above, I created Odd-Even 3DI Swap (https://www.aaroads.com/forum/index.php?topic=21718.0) thread in the Fictional Section over a year ago as a what if? exercise.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: hotdogPi on April 23, 2019, 03:48:28 PM
Quote from: PHLBOS on April 23, 2019, 03:36:28 PM
The issue with the current odd/even 3dis and their intended assignments/designations is that there are more odd 3di numbers (1XX, 3XX, 5XX, 7XX & 9XX) available then even 3di numbers (2XX, 4XX, 6XX & 8XX);

Very few 9XX numbers are in use.

Quote from: PHLBOS on April 23, 2019, 03:36:28 PM
but there are more bypasses/beltways/through-city routes (typical candidates for even 3dis) out there than there are spur routes (typical odd 3dis).

The method that I mentioned before gives more odd numbers than even numbers. Let's take Connecticut's freeway system as an example. CT 8 is pretty clearly odd, and it would be odd even (no pun intended) if it went to the Mass Pike. (If it went to MA 57, possibly not.) CT 2 and CT 9 would be odd, as they connect the Hartford metro area to another smaller metro area by a near-straight line. I-384, CT 11, CT 40, CT 25, CT 2A, US 6 bypass near RI, both freeway segments of US 7, and the airport connector are spurs, and therefore get odd numbers. I-684 should be odd as a route out of the NYC area, although it's only in CT for about a mile.

This leaves the existing 2dis, CT 15 (functions more as a 2di if you ignore the truck restrictions), I-291 (correctly even), I-691 (could go either way; it's both a Hartford bypass and a straight line), CT 72 (half spur half bypass), the Milford Connector (doesn't need a number), CT/RI 78 (even), US 6 bypass of Willimantic (nowhere near an Interstate), CT 3 (even), and CT 2 near Foxwoods (CT 2 is sufficient). Of those, I listed 3 even and 2 that could go either way, while I listed many odd ones above.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: skluth on April 23, 2019, 04:13:36 PM
Quote from: hbelkins on April 09, 2019, 07:30:06 PM
Quote from: Beltway on April 09, 2019, 05:16:18 PM
Quote from: skluth on April 09, 2019, 01:10:37 AM
I don't care if they're numbered as even or odd 3DIs. As long as they're not labeled 2DIs like I-12 or I-97.

What should I-12 be?

I-10. The loop into NO should be I-6.

I agree I-12 should be I-10. However, I'd extend I-55 and I-59 into New Orleans rather than ending them in LaPlace and Slidell. The stretch between Baton Rouge and LaPlace would be a 3DI of either I-10 or I-55. If the I-10 section along Claiborne Avenue is removed (which is more probable than you might think), have I-55 end at the Mississippi River and I-59 end at I-55 west of City Park.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: roadman65 on April 23, 2019, 06:16:08 PM
Quote from: 1 on April 08, 2019, 09:22:27 PM
Quote from: SoCal Kid on April 08, 2019, 09:19:28 PM
Quote from: hbelkins on April 08, 2019, 09:15:16 PM
Quote from: SoCal Kid on April 08, 2019, 02:05:15 PM
Wikipedia

That's your first mistake right there.  :bigass:
?

Wikipedia articles on roads are pretty accurate. There are no issues with POV pushing or living person biographies, and vandalism is relatively rare compared to more popular and more controversial articles.
Isn't some of the Wikipedia articles written by NE2?  That might explain why they are accurate cause he is pretty good about roads and history about them.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: roadman65 on April 23, 2019, 06:25:51 PM
Quote from: PHLBOS on April 23, 2019, 03:36:28 PM
Quote from: TheStranger on April 09, 2019, 11:08:37 PM
- I-76 once did go into Pittsburgh if I'm not mistaken (though pretty much all of the former I-80S from Ohio east is now I-76).
Correct, I-76 went into Pittsburgh until 1972 when it shifted onto its current routing (replacing I-80S).  The old I-76 west of the PA Turnpike's Exit 57 (Pittsburgh interchange) became the current I-376.
_____________________________________
The issue with the current odd/even 3dis and their intended assignments/designations is that there are more odd 3di numbers (1XX, 3XX, 5XX, 7XX & 9XX) available then even 3di numbers (2XX, 4XX, 6XX & 8XX); but there are more bypasses/beltways/through-city routes (typical candidates for even 3dis) out there than there are spur routes (typical odd 3dis).

Note: not an intended plug, mind you; but given the above, I created Odd-Even 3DI Swap (https://www.aaroads.com/forum/index.php?topic=21718.0) thread in the Fictional Section over a year ago as a what if? exercise.
Also when I-76 ended in Pittsburgh, I-79 used the planned I-279 (as that freeway was not yet constructed north of the Allegeny River and the current I-79 from I-376 to I-279 was to be I-279. 

Just like in Philly with I-76 and I-676 PennDOT flipped the route numbers with I-79.

Of course I-70 also was planned to be through Pittsburgh as well, and that got shifted onto what it is now including the non interstate standard freeway from Washington to New Stanton.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Beltway on April 23, 2019, 08:54:47 PM
Quote from: ilpt4u on April 21, 2019, 11:51:50 AM
Quote from: Verlanka on April 21, 2019, 08:23:21 AM
If that's the case, then I-476 should be renumbered I-776 or I-976 (I-576 is already taken).
I would just swap the 376 and 476 designations in PA

I always favored an I-x95 for the western bypass of Philadelphia.  So the Mid-County Expressway would be I-695 and the Turnpike between Plymouth Meeting and I-95 at Bristol would be I-695.

The Turnpike between Valley Forge and Plymouth Meeting could still be I-276.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Henry on April 24, 2019, 10:28:05 AM
Honestly, I could care less. However (and this is slightly off topic), I've always wondered why they need two A-440s up in Canada (Montreal and Quebec City); doesn't that create the potential for confusion? One of them ought to be renumbered to avoid that problem.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: PHLBOS on April 24, 2019, 11:18:45 AM
Quote from: SoCal Kid on April 08, 2019, 02:05:15 PM
"In the case of an auxiliary Interstate highway which has both ends at Interstates but not the same Interstate, some states treat these as bypasses while others treat these as spurs." - Wikipedia.
I meant to chime on this earlier...  Here's how odd/even 3dis are defined by Rand McNally (the below is listed on atlases and most of their road maps):

First digit odd - route spurs into a city

First digit even - route goes through or around a city.

Quote from: Beltway on April 23, 2019, 08:54:47 PM
Quote from: ilpt4u on April 21, 2019, 11:51:50 AM
Quote from: Verlanka on April 21, 2019, 08:23:21 AM
If that's the case, then I-476 should be renumbered I-776 or I-976 (I-576 is already taken).
I would just swap the 376 and 476 designations in PA

I always favored an I-x95 for the western bypass of Philadelphia.  So the Mid-County Expressway would be I-695 and the Turnpike between Plymouth Meeting and I-95 at Bristol would be I-695.

The Turnpike between Valley Forge and Plymouth Meeting could still be I-276.
Given the above, what would you have the Northeast Extension of the PA Turnpike designated as?
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Mergingtraffic on April 24, 2019, 12:25:36 PM
I always thought if an even 3DI both ends at another interstate its even b/c it's a connector.  I-684 in NY goes from I-84 to I-287.  It's not a loop or bypass but it connects to two  interstates at each end.  Odd numbered are for spurs where one end does not end at an interstate.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Beltway on April 24, 2019, 04:47:21 PM
Quote from: PHLBOS on April 24, 2019, 11:18:45 AM
Quote from: Beltway on April 23, 2019, 08:54:47 PM
I always favored an I-x95 for the western bypass of Philadelphia.  So the Mid-County Expressway would be I-695 and the Turnpike between Plymouth Meeting and I-95 at Bristol would be I-695.
The Turnpike between Valley Forge and Plymouth Meeting could still be I-276.
Given the above, what would you have the Northeast Extension of the PA Turnpike designated as?

Really it was too long for an auxiliary route. 

But an I-x80 or I-x78 could have worked.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: thspfc on April 24, 2019, 05:57:18 PM
If the route functions like a bypass (I-635 in Texas would be an example), it should be an even number. If it functions like a spur to another Interstate (205 in Cal), it should be an odd number.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: ilpt4u on April 24, 2019, 06:13:34 PM
Quote from: thspfc on April 24, 2019, 05:57:18 PM
If the route functions like a bypass (I-635 in Texas would be an example), it should be an even number. If it functions like a spur to another Interstate (205 in Cal), it should be an odd number.
And when it functions like neither? Looking at you, IL I-290...Its a spur off its Parent that connects the Western suburbs and the West side of Chicago, but happens to touch its Parent on both ends Downtown and in Schaumburg. But it really doesn't "Bypass"  anything...

Of course it has been stated that the I-290 designation could/should go away, with I-88 and I-355 (which in your ideal, probably is a better I-455) replacing most of the current 290 designation, and a new number between them, say I-188

And historically, it used to carry the I-90 designation
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: kphoger on April 25, 2019, 04:26:06 PM
Quote from: ilpt4u on April 24, 2019, 06:13:34 PM

Quote from: thspfc on April 24, 2019, 05:57:18 PM
If the route functions like a bypass (I-635 in Texas would be an example), it should be an even number. If it functions like a spur to another Interstate (205 in Cal), it should be an odd number.

And when it functions like neither?

Irrational number.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Ned Weasel on April 25, 2019, 04:48:25 PM
Quote from: kphoger on April 25, 2019, 04:26:06 PM
Quote from: ilpt4u on April 24, 2019, 06:13:34 PM

Quote from: thspfc on April 24, 2019, 05:57:18 PM
If the route functions like a bypass (I-635 in Texas would be an example), it should be an even number. If it functions like a spur to another Interstate (205 in Cal), it should be an odd number.

And when it functions like neither?

Irrational number.

I-Pi sounds like a sweet Interstate.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: US 89 on April 25, 2019, 04:51:09 PM
Quote from: stridentweasel on April 25, 2019, 04:48:25 PM
Quote from: kphoger on April 25, 2019, 04:26:06 PM
Quote from: ilpt4u on April 24, 2019, 06:13:34 PM

Quote from: thspfc on April 24, 2019, 05:57:18 PM
If the route functions like a bypass (I-635 in Texas would be an example), it should be an even number. If it functions like a spur to another Interstate (205 in Cal), it should be an odd number.

And when it functions like neither?

Irrational number.

I-Pi sounds like a sweet Interstate.

But if you take Route e to I pi, it becomes -1!
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: thspfc on April 25, 2019, 05:02:58 PM
Quote from: ilpt4u on April 24, 2019, 06:13:34 PM
Quote from: thspfc on April 24, 2019, 05:57:18 PM
If the route functions like a bypass (I-635 in Texas would be an example), it should be an even number. If it functions like a spur to another Interstate (205 in Cal), it should be an odd number.
And when it functions like neither? Looking at you, IL I-290...Its a spur off its Parent that connects the Western suburbs and the West side of Chicago, but happens to touch its Parent on both ends Downtown and in Schaumburg. But it really doesn't "Bypass"  anything...

Of course it has been stated that the I-290 designation could/should go away, with I-88 and I-355 (which in your ideal, probably is a better I-455) replacing most of the current 290 designation, and a new number between them, say I-188

And historically, it used to carry the I-90 designation
The 290 designation makes sense because both ends of it are at I-90, even if it isn't a bypass. Though it should be replaced by I-88 and I-355 as you said.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: PHLBOS on April 25, 2019, 05:24:18 PM
Quote from: Mergingtraffic on April 24, 2019, 12:25:36 PMI always thought if an even 3DI both ends at another interstate its even b/c it's a connector.  I-684 in NY goes from I-84 to I-287.  It's not a loop or bypass but it connects to two interstates at each end.
It's worth noting that I-684 was originally proposed & built as I-87 and the oldest of segments (the southernmost portion to Armonk) indeed had I-87 signage from October 1968 to January 1, 1970.

While that highway indeed links to two Interstates (84 & 287) at both ends; there are a some examples of odd 3dis connecting to two Interstates.  I-195 in RI/MA is one such example; granted the eastern end was the result of MA 25 north of I-195 becoming the southern extension of I-495 during the 1980s.

Quote from: Beltway on April 24, 2019, 04:47:21 PM
Quote from: PHLBOS on April 24, 2019, 11:18:45 AM
Quote from: Beltway on April 23, 2019, 08:54:47 PM
I always favored an I-x95 for the western bypass of Philadelphia.  So the Mid-County Expressway would be I-695 and the Turnpike between Plymouth Meeting and I-95 at Bristol would be I-695.
The Turnpike between Valley Forge and Plymouth Meeting could still be I-276.
Given the above, what would you have the Northeast Extension of the PA Turnpike designated as?
Really it was too long for an auxiliary route. 

But an I-x80 or I-x78 could have worked.
Given that the Northeast Extension's northern terminus is at I-81; one could've used I-x81.

As far as length; both pieces of I-476 (Blue Route & Northeast Extension) total roughly 131 miles; 111 of those miles being the NE Extension.  So I-476, in total, is longer than I-495 in MA by about 11 miles.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: ilpt4u on April 25, 2019, 05:33:47 PM
Quote from: thspfc on April 25, 2019, 05:02:58 PM
The 290 designation makes sense because both ends of it are at I-90, even if it isn't a bypass. Though it should be replaced by I-88 and I-355 as you said.
The number is logical as an Even 3DI because both ends are I-90, agreed

I was simply stating the Rules/Guidelines need to be a bit more pronounced than "Bypass"  vs "Spur"
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: thspfc on April 25, 2019, 05:54:04 PM
Quote from: ilpt4u on April 25, 2019, 05:33:47 PM
Quote from: thspfc on April 25, 2019, 05:02:58 PM
The 290 designation makes sense because both ends of it are at I-90, even if it isn't a bypass. Though it should be replaced by I-88 and I-355 as you said.
The number is logical as an Even 3DI because both ends are I-90, agreed

I was simply stating the Rules/Guidelines need to be a bit more pronounced than "Bypass"  vs "Spur"
True
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: kphoger on April 25, 2019, 06:07:03 PM
I-290 is a bypass of Des Plaines.  Problem solved.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: ilpt4u on April 25, 2019, 06:20:48 PM
Quote from: kphoger on April 25, 2019, 06:07:03 PM
I-290 is a bypass of Des Plaines.  Problem solved.
:bigass:

O'Hare is probably more fittingly accurate, despite a tighter ORD Bypass Tollway being built for Future I-490

Considering it was originally designated as I-90, I don't think it really fits to call it a "Bypass."  If others thinks it resembles a Bypass, so be it
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Flint1979 on April 25, 2019, 07:43:40 PM
Quote from: ilpt4u on April 24, 2019, 06:13:34 PM
Quote from: thspfc on April 24, 2019, 05:57:18 PM
If the route functions like a bypass (I-635 in Texas would be an example), it should be an even number. If it functions like a spur to another Interstate (205 in Cal), it should be an odd number.
And when it functions like neither? Looking at you, IL I-290...Its a spur off its Parent that connects the Western suburbs and the West side of Chicago, but happens to touch its Parent on both ends Downtown and in Schaumburg. But it really doesn't "Bypass"  anything...

Of course it has been stated that the I-290 designation could/should go away, with I-88 and I-355 (which in your ideal, probably is a better I-455) replacing most of the current 290 designation, and a new number between them, say I-188

And historically, it used to carry the I-90 designation
I-290 bypasses both the Kennedy Expressway stretch and the O'Hare area. It's basically an alternate route.
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: Beltway on April 25, 2019, 09:21:28 PM
Quote from: PHLBOS on April 25, 2019, 05:24:18 PM
Quote from: Beltway on April 24, 2019, 04:47:21 PM
Quote from: PHLBOS on April 24, 2019, 11:18:45 AM
]Given the above, what would you have the Northeast Extension of the PA Turnpike designated as?
Really it was too long for an auxiliary route.  But an I-x80 or I-x78 could have worked.
Given that the Northeast Extension's northern terminus is at I-81; one could've used I-x81.
As far as length; both pieces of I-476 (Blue Route & Northeast Extension) total roughly 131 miles; 111 of those miles being the NE Extension.  So I-476, in total, is longer than I-495 in MA by about 11 miles.

I thought about an I-x81, but decided not to given the low-grade connection to I-81.

How about a mainline route like I-67?  Wasn't that discussed for the western part of the state?
Title: Re: Should auxiliary Interstates be numbered like spurs or like bypasses?
Post by: PHLBOS on April 30, 2019, 09:41:37 AM
Quote from: Beltway on April 25, 2019, 09:21:28 PM
Quote from: PHLBOS on April 25, 2019, 05:24:18 PM
Quote from: Beltway on April 24, 2019, 04:47:21 PM
Quote from: PHLBOS on April 24, 2019, 11:18:45 AM
Given the above, what would you have the Northeast Extension of the PA Turnpike designated as?
Really it was too long for an auxiliary route.  But an I-x80 or I-x78 could have worked.
Given that the Northeast Extension's northern terminus is at I-81; one could've used I-x81.
As far as length; both pieces of I-476 (Blue Route & Northeast Extension) total roughly 131 miles; 111 of those miles being the NE Extension.  So I-476, in total, is longer than I-495 in MA by about 11 miles.
I thought about an I-x81, but decided not to given the low-grade connection to I-81.
IIRC, a remedy for that connection is now in the works. 
Your suggested I-x78 wouldn't work because although the two highway cross each other, they don't directly interchange w/one another.  One needs to use US 22 and possibly PA 309 for connections.  Your suggested I-x80 alternative has an issue regarding I-476's connection w/I-80 involves going through a signalized intersection w/PA 940.

Quote from: Beltway on April 25, 2019, 09:21:28 PM
How about a mainline route like I-67?  Wasn't that discussed for the western part of the state?
Over the years/decades, there's been three different proposals out there for I-67; not one of them is in or involves PA.  The western PA that's been touted in this forum is a fictional one.

That said, and there probably already a fictional thread on such, a more desirable 2di candidate for the NE Extension would be to have it be a part of an overall northern extension of I-85.  Yes, such would be concurrent w/I-95 in many areas (utilizing only current Interstates along the way) but there's enough parallel or semi-parallel highways in key regions where the two could be separated for some distances.