The numbering of the US Highway system

[vdeane]

I believe the US highway system used x1 and x0 as the primary transcontinentals with x5 being a secondary transcontinental.

[TheStranger]

I believe the US highway system used x1 and x0 as the primary transcontinentals with x5 being a secondary transcontinental.

US 15, 25, 45, 65, 75, 85, and 95 fit that...but US 5, 35, and decommissioned 55 don't - and 95 was originally created as a very short route in Idaho.

[yakra]

Well, US5 just happened to be at a very thin part of the country.

[agentsteel53]

Well, US5 just happened to be at a very thin part of the country.

I'm just imagining how much difficulty Chile would have in developing a grid-based system.  How do they manage their numbering?

[ctsignguy]

if i recall correctly, x1 and x5 were designated as the primary N-S routes simply because the country was wider than using x5 or x1 routes alone....you got pretty good E-W coverage with the x0 routes....of course US 35 was a late-comer to the party, as were the US 95 extensions...

[Quillz]

Interestingly enough, though, both US 10 and US 90 were never designed to be full transcontinental highways. The same goes with US 20... It used to end at the east end of Yellowstone until the 1940s, when it was extended west to Newport, OR. This is why Oregon violates the grid system. (US 26 should be south of US 20 and north of US 30, but it's not.)

It also comes down to the fact that many US highways have been extended, truncated or realigned since 1926. This is why US 41, for example, runs in a very diagonal pattern, why US 6 is somehow way down in LA and why route numbers such as 400 and 412 exist.

[agentsteel53]

why route numbers such as 400 and 412 exist.

that is just capriciousness in numbering - nothing to do with extending old routes.  Those two were formed out of whole cloth in the early 80s.

[Quillz]

why route numbers such as 400 and 412 exist.

that is just capriciousness in numbering - nothing to do with extending old routes.  Those two were formed out of whole cloth in the early 80s.

Oh, I know, I was just saying that the US Route system has seen a lot of changes over the years, so there are many numbers that are located in places that don't make much sense.

For me, US 6 being anywhere close to California has always kind of annoyed me. And then there's the fact that despite the number implying it's *NOT* a transcontinental highway, it was the longest road in America until 1964, at which point US 20 became the longest.

[TheStranger]

Actually, I think the US route system had one huge advantage over the Interstate system: flexibility.

Other than the x1 and x0 routes (and to some extent x5), anything else could be as diagonal as necessary.  Often times this was taken to excessive extremes (52, 62, 68, 33, 35) but usually this allowed for 2 digit routes to be placed wherever needed, as opposed to the issue the Interstates have of running out of 2 digit numbers due to the grid being too closely laid out.

best comparison?  US 11, as opposed to I-81 and I-59 being two entirely seperate interstates on different planes of that grid, following that one corridor.

Having said that, does that explain 44 and 46 being WAY out of the grid?    And how about 59/96!?

[Quillz]

I think it's too flexible, though... There was a reason for 3di, to fill in the gaps and run diagonal if necessary. There are many examples of 3di US Routes that don't get anywhere near their parent, like US-395. Those are the routes that can run diagonal or connect to places the parent won't touch.

[agentsteel53]

I think it's too flexible, though... There was a reason for 3di, to fill in the gaps and run diagonal if necessary. There are many examples of 3di US Routes that don't get anywhere near their parent, like US-395. Those are the routes that can run diagonal or connect to places the parent won't touch.

395 was once upon a time a minor branch of 195 before it was extended extremely southward.  this was even before 95 left the confines of Idaho. 

[TheStranger]

I think it's too flexible, though... There was a reason for 3di, to fill in the gaps and run diagonal if necessary. There are many examples of 3di US Routes that don't get anywhere near their parent, like US-395. Those are the routes that can run diagonal or connect to places the parent won't touch.

As Jake noted, 395 was originally a very minor route once upon a time.  Having said that, a lot of the awkward 2-digit routes don't really seem to have a "parent" and function as their own extended corridors, particularly something as out-of-grid as 59.

[Bickendan]

Interestingly enough, though, both US 10 and US 90 were never designed to be full transcontinental highways. The same goes with US 20... It used to end at the east end of Yellowstone until the 1940s, when it was extended west to Newport, OR. This is why Oregon violates the grid system. (US 26 should be south of US 20 and north of US 30, but it's not.)

Quibble: US 26 in Oregon is exactly where it should be: Between US 20 and 30. It's US 20 and 30 that are in the wrong order; swap them and everything's fine.

But there's little to no point to swapping them, as doing so wouldn't be doing the Public At Large any service (they don't care about the route order), the cost to swap the signs wouldn't be justified, the Historic US 30 shields on OR 100 would make no sense at all, and given that AASHTO would have to sign off on this, I really wouldn't want to give them ammo to force the decommissioning of the US 30 corridor in Oregon on the grounds that it largely duplexes with I-84 and forcing OR 2 to be signed from Astoria to Portland with Bus I-84 taking US 30's place east of Portland. *shudders*

[xonhulu]

Quibble: US 26 in Oregon is exactly where it should be: Between US 20 and 30. It's US 20 and 30 that are in the wrong order; swap them and everything's fine.

But there's little to no point to swapping them, as doing so wouldn't be doing the Public At Large any service (they don't care about the route order), the cost to swap the signs wouldn't be justified, the Historic US 30 shields on OR 100 would make no sense at all, and given that AASHTO would have to sign off on this, I really wouldn't want to give them ammo to force the decommissioning of the US 30 corridor in Oregon on the grounds that it largely duplexes with I-84 and forcing OR 2 to be signed from Astoria to Portland with Bus I-84 taking US 30's place east of Portland. *shudders*

I doubt very much in that scenario that they'd call it OR 2.  My guess is they'd call it OR 30, like they did when they decommed US 99 and US 126 years ago.  If not, then I'd guess they'd go with OR 92, making the Route Number match the Highway Number.

[Quillz]

I know this has nothing to do with the current topic at hand, but do US Route 3di leading digits mean anything?

Like with the Interstate system, when the leading digit is even, it's supposed to connect an Interstate to an Interstate or act as a loop/bypass of its parent route. When the leading digit is odd, it's a spur that is supposed to only connect to an Interstate at one end.

Do the US Route 3di work the same way?

[xonhulu]

I know this has nothing to do with the current topic at hand, but do US Route 3di leading digits mean anything?

Like with the Interstate system, when the leading digit is even, it's supposed to connect an Interstate to an Interstate or act as a loop/bypass of its parent route. When the leading digit is odd, it's a spur that is supposed to only connect to an Interstate at one end.

Do the US Route 3di work the same way?

They were originally assigned in the order that the spur route from that parent was created.  There also seems to be a general pattern of north-to-south for odd 2dus and east-to-west for even 2dus.  Of course, as routes were decommissioned and others added, many available numbers got recycled to new routes.

[Quillz]

I know this has nothing to do with the current topic at hand, but do US Route 3di leading digits mean anything?

Like with the Interstate system, when the leading digit is even, it's supposed to connect an Interstate to an Interstate or act as a loop/bypass of its parent route. When the leading digit is odd, it's a spur that is supposed to only connect to an Interstate at one end.

Do the US Route 3di work the same way?

They were originally assigned in the order that the spur route from that parent was created.  There also seems to be a general pattern of north-to-south for odd 2dus and east-to-west for even 2dus.  Of course, as routes were decommissioned and others added, many available numbers got recycled to new routes.

When you say "the order from that parent," do you mean sequential order, like the first spur built was 1xx, or do you mean in order geographically, from north to south?

[Bickendan]

If my understanding is correct, the former. IIRC, the discussion around US 666's renumbering to US 491 was that US 666 was simply the sixth US 66 spur.

Quibble: US 26 in Oregon is exactly where it should be: Between US 20 and 30. It's US 20 and 30 that are in the wrong order; swap them and everything's fine.

But there's little to no point to swapping them, as doing so wouldn't be doing the Public At Large any service (they don't care about the route order), the cost to swap the signs wouldn't be justified, the Historic US 30 shields on OR 100 would make no sense at all, and given that AASHTO would have to sign off on this, I really wouldn't want to give them ammo to force the decommissioning of the US 30 corridor in Oregon on the grounds that it largely duplexes with I-84 and forcing OR 2 to be signed from Astoria to Portland with Bus I-84 taking US 30's place east of Portland. *shudders*

I doubt very much in that scenario that they'd call it OR 2.  My guess is they'd call it OR 30, like they did when they decommed US 99 and US 126 years ago.  If not, then I'd guess they'd go with OR 92, making the Route Number match the Highway Number.

The highway number is 2W, as it's still the Columbia River Highway.

[Quillz]

I'm not really a fan of numbering spurs based on the order they were built. I'd prefer a system where, in each given state, the westernmost 3di is numbered 2xx, then the second westernmost is 4xx, etc. Then the southernmost would be 1xx, while 9xx would be the northernmost.

[xonhulu]

If my understanding is correct, the former. IIRC, the discussion around US 666's renumbering to US 491 was that US 666 was simply the sixth US 66 spur. [The highway number is 2W, as it's still the Columbia River Highway.

I'm pretty sure they changed it to 92, although ODOT's documentation is pretty mixed.  The HSHO document lists it in the table of contents as Hwy 2W, but when you go to the actual page, the title heading says "Lower Columbia River Hwy (92)."  The source I consider most definitive is the 2009 State Hwy Map on ODOT's website (link:  http://egov.oregon.gov/ODOT/TD/TDATA/rics/docs/2009_State_Hwy_Map.pdf  ) and it designates the highway as 92, so I go with that.  

I actually hope it is still considered Hwy 2W if your scenario comes true, as OR 2 would be a better number than OR 92, but once again I think they'd just make it OR 30.  Of course, my real preference would be to retain US 30.  If it came down to AASHTO trying to force its decommissioning, I'd prefer one of the following scenarios:

1.  Oregon and Idaho ignore AASHTO and keep US 30 as it is;

2.  Washington signs US 30 on WA 14 to Umatilla, then Oregon routes it on either US 395/I-84 or US 730/OR 37 to Pendleton.  Idaho could also restore US 30 to some old alignments.

[Quillz]

I don't think US-30 is going away. It might be concurrent with I-84 for almost its entire length in Oregon, but overall, the concurrency is a fraction of US-30's total length. I don't see why AASHTO would mess with US-30 in Oregon at all.

[xonhulu]

I don't think US-30 is going away. It might be concurrent with I-84 for almost its entire length in Oregon, but overall, the concurrency is a fraction of US-30's total length. I don't see why AASHTO would mess with US-30 in Oregon at all.

Yeah, I don't see it happening, either.  The application to decommission would have to be made jointly by OR and ID, and I've never seen any sign that those states want to do away with it.  They still seem to find the route useful.

[Michael in Philly]

Well, US5 just happened to be at a very thin part of the country.

I'm just imagining how much difficulty Chile would have in developing a grid-based system.  How do they manage their numbering?

Can you read Spanish?

http://es.wikipedia.org/wiki/Rutas_nacionales_de_Chile

If I'm understanding this right, single-digit numbers are reserved for "longitudinals" - north-south routes above a certain minimum length, then everything else is by region or province (10s are in one area, 20s in the next....  looks like these numbers increase from north to south, or rather number classes increase from north to south - the 10s being in the northernmost part of the country and so on.)

[Michael in Philly]

Actually, I think the US route system had one huge advantage over the Interstate system: flexibility.

Other than the x1 and x0 routes (and to some extent x5), anything else could be as diagonal as necessary.  Often times this was taken to excessive extremes (52, 62, 68, 33, 35) but usually this allowed for 2 digit routes to be placed wherever needed, as opposed to the issue the Interstates have of running out of 2 digit numbers due to the grid being too closely laid out.

best comparison?  US 11, as opposed to I-81 and I-59 being two entirely seperate interstates on different planes of that grid, following that one corridor.

Having said that, does that explain 44 and 46 being WAY out of the grid?    And how about 59/96!?

44 and 46 were relative latecomers.  (I've seen early-30s maps of the region which don't show them.)  I suppose someone decided there needed to be two-digit routes there and they...picked numbers out of a hat?  (Is it possible that 44 was the lowest number available?)  So they're analogous to how we got I-99.  And how many people here remember that when I-68 was built, it was called US 48?

[Scott5114]

I'm not really a fan of numbering spurs based on the order they were built. I'd prefer a system where, in each given state, the westernmost 3di is numbered 2xx, then the second westernmost is 4xx, etc. Then the southernmost would be 1xx, while 9xx would be the northernmost.

The "I" in "3di" stands for Interstate. A three-digit US route is more properly called a 3dus.

In US 66's case, I know the easternmost branch was 166, then 266 split off further east, then 366, and 466 was in CA. I was under the impression that 666 was an original US route, however, so it would be the pattern breaker there.

I'm thinking there really wasn't too much thought given to it.