Wondering if anyone can answer this question I have had for a long time. Why is I-235 in OK numbered as a loop route and not a spur route? I have not come across anything suggesting that it follows I-44 back to I-35 and was simply unsigned like I-444. Was it originally intended to connect back with I-35 somewhere and was cancelled?
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
It ends at I-44 and at I-35. Both ends are at Interstates, therefore it has an even first digit.
It looks like it's a freeway north of I-44. Is there a chance 235 could be extended up to the Kilpatrick/soon to be I-240?
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
Yeah, there are plenty of even 3dis that begin at one interstate and end at another. I-225 in Denver, 675 in Atlanta, 635 in Kansas City all come to mind. But there's also things like I-170 in St Louis, which connects I-270 to I-64 and junctions I-70 in the middle. I was always under the impression that there was no firm rule for this type of situation and it was more of a question of local DOT preference.
Sometimes it's also helpful to look at what purpose a 3di serves in its local freeway network - beltways or bypasses or city through routes get an even number, while spurs get an odd number. Interstates like 215 in Salt Lake or 440 in Nashville may begin and end at different interstates, but they're so obviously beltways that an even first digit is very much appropriate.
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
I have not heard of that rule. Both I-135 & I-335 both terminate at a junction with another interstate.
Quote from: FakeMikeMorgan on August 09, 2021, 10:31:12 AM
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
I have not heard of that rule. Both I-135 & I-335 both terminate at a junction with another interstate.
There's examples of both even first digit and odd first digit with interstates terminating at another interstate that isn't the parent. Imo, it should be more like how the 3di functions, than what its endpoints are. If it functions like a bypass/beltway, give it an even first digit. If it functions like a spur, give it an odd first digit. With the exception of 370 (which is obviously a bypass), I think the St Louis area (including the two "state route 3di" in the area) is a good example, with 270 and 255 with an even first digit, because they're part of the city's beltway, and 170 and 364 with an odd first digit, because they're more just local connectors, and aren't really used as a long distance bypass.
Quote from: bugo on August 09, 2021, 08:10:21 AM
It ends at I-44 and at I-35. Both ends are at Interstates, therefore it has an even first digit.
There are multiple odd numbered 3di's that end at interstates (like my I-135 & I-335 examples I gave in another comment.)
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
The original interstate guidance was odd 3DI's are spurs and even 3DI's are bypasses and through routes. It's generally followed, but that guidance is more an issue on forums like this one than with drivers and state DOTs.
I-464 connects I-64 and I-264.
I-270 connects I-70 and I-495.
I-440 connects I-40 and I-30.
I-295 connects I-95 / I-495 and I-695 (soon to be I-395).
I-276 connects I-76 and I-95 / I-295.
There's examples of both.
My general rules for even vs. odd:
EVEN
- Any route that forms a complete 360 degree loop or ends at the same interstate on both ends should automatically be in this category. (I-465 IN)
- Any route that functions primarily as a loop or bypass around a city, ending on an interstate at both ends. (I-469 IN)
-The designation is allowed to continue past its last interstate junction to end at another route or location (see I-635 TX, bypass of Dallas for I-35E but continues to serve the DFW airport.
- Any connector route ending on an interstate at BOTH ends WITHIN a metropolitan area (this criteria is very gray, though I would give even 3dis the benefit of the doubt. (I-235 OK, I-275 TN)
- Interstates that form a part of a bypass route but are not the complete route (I-865 IN, Proposed I-870 IL)
ODD
- Any route with only ONE interstate junction automatically fits into this category. (I-565 AL, I-155 TN/MO)
- Any route that does not terminate on an interstate at both ends (unless a continuation of an obvious loop/bypass like I-635 as noted above). (I-787 NY)
- Any route that spurs from an interstate to a metro area that the non-spur route doesn't enter (I-380 PA)
- Any route connecting one or more metropolitan areas (I-135 KS, I-380 IA)
Other Gray Areas/Examples
I-505 CA - Some argue it is a bypass of Sacramento. While it may act in that way it is primarily a spur of I-5 to connect directly (on a straight alignment) to the Bay Area
I-520 GA/SC and I-540 NC - Since these routes were originally spurs with one interstate junction (and weren't originally to be full loops) their numbering is grandfathered in. On the flip side, I-476 was originally a western bypass of Philadelphia that ended up getting extended over the existing PA Turnpike NE Extension
This is just how I interpret even/odd, I'm sure there is room for debate and I am willing to discuss.
Quote from: I-55 on August 10, 2021, 09:10:30 PM
- Any connector route ending on an interstate at BOTH ends WITHIN a metropolitan area (this criteria is very gray, though I would give even 3dis the benefit of the doubt. (I-235 OK, I-275 TN)
I'll just go with whatever number is available, and preferably the lower first digit. If a state used 2, 4 and 6 on these type of connector routes, and have a new one for a 3di with a choice of 1 or 8 as a first digit, I would prefer 1 gets used over 8 even though maybe an even number would be preferred.
Also, I have a feeling that I-270 MD is numbered I-270 because in the I-70S days, what is now I-270 Spur is already numbered as I-270, so it's easier to extend that numbering north instead of using a new number like I-470 for even or I-570 for odd.
Quote from: mvak36It looks like it's a freeway north of I-44. Is there a chance 235 could be extended up to the Kilpatrick/soon to be I-240?
Broadway Extension going North of the I-44/I-235 interchange could indeed be signed as I-235 up to the Kilpatrick Turnpike once the KT is signed as I-240. Broadway Extension went through a complete re-build and upgrade about 20 years ago. I can't see anything about it that doesn't live up to Interstate standards. Plus the interchange with I-44 and I-235 has been going through a, um,
significant re-build for the better part of a decade (or more). Once that interchange is complete there should be nothing holding back the possibility of a I-235 naming extension up to the Kilpatrick.
If the matter was up to me, I'd put in the application for re-naming Broadway Extension as I-235 at the same time I-240 is signed over the Kilpatrick.
Quote from: I-55 on August 10, 2021, 09:10:30 PM
My general rules for even vs. odd:
What's your thought on I-526 in Charleston? That only has one interstate junction (I-26), but it's very clearly intended to be a beltway route, and both ends are at the same road although it isn't an interstate (US 17).
Quote from: US 89 on August 11, 2021, 01:32:30 AM
Quote from: I-55 on August 10, 2021, 09:10:30 PM
My general rules for even vs. odd:
What's your thought on I-526 in Charleston? That only has one interstate junction (I-26), but it's very clearly intended to be a beltway route, and both ends are at the same road although it isn't an interstate (US 17).
Ask FritzOwl to renumber it to I-299, and I-140 in Wilmington (similar description as I-526) to I-499 :bigass:
Quote from: skluth on August 10, 2021, 03:24:12 PM
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
The original interstate guidance was odd 3DI's are spurs and even 3DI's are bypasses and through routes. It's generally followed, but that guidance is more an issue on forums like this one than with drivers and state DOTs.
Were any of the original odd-numbered 3di routes
not open-ended spurs?
Were any of the original even-numbered 3di routes
not connectors?
Quote from: kphoger on August 11, 2021, 09:47:38 AM
Quote from: skluth on August 10, 2021, 03:24:12 PM
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
The original interstate guidance was odd 3DI's are spurs and even 3DI's are bypasses and through routes. It's generally followed, but that guidance is more an issue on forums like this one than with drivers and state DOTs.
Were any of the original odd-numbered 3di routes not open-ended spurs?
Were any of the original even-numbered 3di routes not connectors?
I-495, New York
Quote from: 1 on August 11, 2021, 09:49:49 AM
Quote from: kphoger on August 11, 2021, 09:47:38 AM
Quote from: skluth on August 10, 2021, 03:24:12 PM
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
The original interstate guidance was odd 3DI's are spurs and even 3DI's are bypasses and through routes. It's generally followed, but that guidance is more an issue on forums like this one than with drivers and state DOTs.
Were any of the original odd-numbered 3di routes not open-ended spurs?
Were any of the original even-numbered 3di routes not connectors?
I-495, New York
495 is a weird case for two reasons:
- The original Interstate 495 designation only went from the current New Jersey Turnpike/NJ 495 junction east to I-295. The portion between the Lincoln Tunnel and the Queens Midtown Tunnel ended up being (in retrospect, unsurprisingly) shelved.
- However, the overall 495 route (including what had been NY 495 until the 1980s) was slated to reconnect to I-95 in Connecticut. That ended up not being built at all.
---
Thinking of original 3dis that seem to defy the obvious classifications:
I-605 in metro Los Angeles was never intended as a belt route/loop, but functionally always was a double-ended spur from I-5
The Bay Area's I-280 in the 1950s plans is a loop route...for US 101, not for I-80. (So this is in a way similar to modern I-140 and I-526 in the Carolinas). Until the late 1960s, I-80 was planned to end AT I-280! (Which ended up being nixed after the freeway revolts, resulting in modern 280 being rerouted onto old US 101 and 1964-1968 Route 87 instead, and 80 permanently ending at the Central Freeway instead of briefly running on it to lead to the never-built Western Freeway)
Quote from: US 89 on August 11, 2021, 01:32:30 AM
Quote from: I-55 on August 10, 2021, 09:10:30 PM
My general rules for even vs. odd:
What's your thought on I-526 in Charleston? That only has one interstate junction (I-26), but it's very clearly intended to be a beltway route, and both ends are at the same road although it isn't an interstate (US 17).
The main expectation of an even 3di is that you can drive between two interstate junctions. That's why my trump card for odd 3di is that there's only one interstate junction. In the cases of I-526 SC and I-140 NC, there's only one interstate junction. I should've explained under the bypass criteria that it applies for situations where the main bypass movement remains within the interstate system rather than end on a non-interstate route. If 526 was numbered as a US route or state route of US-17, I would recommend an even first digit,
but being designated as an interstate it should be numbered in respect to its relation to other interstates.
Quote from: kphoger on August 11, 2021, 09:47:38 AM
Quote from: skluth on August 10, 2021, 03:24:12 PM
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
The original interstate guidance was odd 3DI's are spurs and even 3DI's are bypasses and through routes. It's generally followed, but that guidance is more an issue on forums like this one than with drivers and state DOTs.
Were any of the original odd-numbered 3di routes not open-ended spurs?
Were any of the original even-numbered 3di routes not connectors?
I don't know the full history of the Long Island Expressway, aka I-495. But it's clearly a spur from the city going east to what was once a bunch of farmland on Long Island and it's history goes back to the 50's. That makes it early in the history of the system. There may be others, but I'm not big on whether 3di routes begin with even or odd numbers anymore. Too many exceptions these days to bother.
Quote from: skluth on August 11, 2021, 05:23:12 PM
Quote from: kphoger on August 11, 2021, 09:47:38 AM
Quote from: skluth on August 10, 2021, 03:24:12 PM
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
The original interstate guidance was odd 3DI's are spurs and even 3DI's are bypasses and through routes. It's generally followed, but that guidance is more an issue on forums like this one than with drivers and state DOTs.
Were any of the original odd-numbered 3di routes not open-ended spurs?
Were any of the original even-numbered 3di routes not connectors?
I don't know the full history of the Long Island Expressway, aka I-495. But it's clearly a spur from the city going east to what was once a bunch of farmland on Long Island and it's history goes back to the 50's. That makes it early in the history of the system. There may be others, but I'm not big on whether 3di routes begin with even or odd numbers anymore. Too many exceptions these days to bother.
Right. What I was getting at is this: was it ever a real rule, even in the beginning?
Quote from: skluth on August 11, 2021, 05:23:12 PM
Quote from: kphoger on August 11, 2021, 09:47:38 AM
Quote from: skluth on August 10, 2021, 03:24:12 PM
Quote from: Anthony_JK on August 09, 2021, 05:58:34 AM
I'm guessing that even numbered 3di's are allowed as connectors between Interstate routes, not just as loops or bouncing back to its originator route. Odd numbered 3di's are allowed for spurs only that terminate at non-controlled access highways.
The original interstate guidance was odd 3DI's are spurs and even 3DI's are bypasses and through routes. It's generally followed, but that guidance is more an issue on forums like this one than with drivers and state DOTs.
Were any of the original odd-numbered 3di routes not open-ended spurs?
Were any of the original even-numbered 3di routes not connectors?
I don't know the full history of the Long Island Expressway, aka I-495. But it's clearly a spur from the city going east to what was once a bunch of farmland on Long Island and it's history goes back to the 50's. That makes it early in the history of the system. There may be others, but I'm not big on whether 3di routes begin with even or odd numbers anymore. Too many exceptions these days to bother.
The original I-495 designation did not extend into Long Island (the region, not the physical island) itself, ending at I-295 (what was then I-78) and starting at I-95 in New Jersey.
A later route that has a similar sort of vibe to the original I-495 is the designated I-880 between I-80 and I-280 in the Bay Area - not really a loop route at all, but happening to have junctions with two Interstates. It also was a time where no odd-numbered x80s were available (which led to the I-580 extension at the same time).
TheStranger, do you have any links to maps of plans for the Bay Area's freeway network?
Quote from: yakra on August 12, 2021, 01:38:19 PM
TheStranger, do you have any links to maps of plans for the Bay Area's freeway network?
Here's the two most relevant ones:
Interstate Yellow Book, 1956:
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.ajfroggie.com%2Froads%2Fyellowbook%2Fsanfrancisco.jpg&hash=bbc1dcefdb6608730337c7421e9a30d9d6cca65a)
Shows the following:
I-680 along today's I-780, today's 680 between Benicia and Warm Springs, today's 262 (the road that in the past has been Route 9/21, US 101E, and partially Route 238), and today's 880 (former 17) between 262 and 101
I-280 along the Route 1/19th Avenue corridor between US 101 in the Presidio, then along today's 280 between the 1/280 junction in southern SF/northern Daly City and 880 (former 17) near Santana Row in SJ, then along 880 (former 17) between Santana Row and 101
I-480 along today's US 101 in the Presidio east of Route 1, then along the never-built section paralleling Lombard/Jefferson, then along the built portion of 480 to I-80
I-80 in SF following the Central Freeway to Fell Street, then the controversial never-built Western Freeway to I-280 in Golden Gate Park (near Kezar Stadium, at the time the 49ers park)
I-5W (later I-580) along the US 50 corridor from Oakland to Dublin. Note the "TO MODESTO" portion, which does tie into a 2021-era CalTrans project, the Route 132 expressway in Modesto that was originally to be part of the 5W routing!
---
1965 SF map
(https://www.cahighways.org/maps/1965sfplans.jpg)
Right after the 1964 renumbering, 280 still shown on the Route 1 corridor. Route 82 (the successor to surface US 101) along today's 280 between US 101 and San Jose Avenue. Route 87 (the same one as the one that exists in San Jose) showing up in planning maps all the way from SJ to the Cesar Chavez (Army) interchange in SF - where stub ramps still exist to this day; today's 280 north of there was to have been part of 87 as well.
---
Here is a bunch of historic planning maps for the Bay Area on this Flickr page - https://www.flickr.com/photos/walkingsf/albums/72157622139053795 = Some notable ones:
- The I-980 corridor (and Route 61) being shown very specifically as the Southern Crossing connector, for a bridge from Oakland to Alameda west to the 280/Cesar Chavez junction. Never built.
(https://live.staticflickr.com/4116/4741575894_85c6eb4637.jpg) (https://flic.kr/p/8dZPjw)The Southern Crossing: A Brief Report (1971) (https://flic.kr/p/8dZPjw) by Erica Fischer (https://www.flickr.com/photos/walkingsf/), on Flickr
- Oakland plans showing both the 980 (24) extension to Southern Crossing, and the also never-built 77:
(https://live.staticflickr.com/4119/4813832808_d39e107f23.jpg) (https://flic.kr/p/8ko9Mo)Oakland: Proposed 1985 Circulation System (1969) (https://flic.kr/p/8ko9Mo) by Erica Fischer (https://www.flickr.com/photos/walkingsf/), on Flickr
- 1970 regional planning map
(https://live.staticflickr.com/4056/4499360416_9af53bcaa0.jpg) (https://flic.kr/p/7RAp6A)Association of Bay Area Governments Regional Plan 1970-1990 (1970) (https://flic.kr/p/7RAp6A) by Erica Fischer (https://www.flickr.com/photos/walkingsf/), on Flickr
On that same page are some Santa Clara County maps showing different proposals from what the state eventually suggested (i.e. the 87 SF-SJ route feeding into 85 in Mountain View, and 280/85 as one corridor from the Presidio to South San Jose)
^ Interesting that there used to be three cities with both US 40 and US 50 (considering that they're both x0), San Francisco, Kansas City and St Louis. Also that US 40/50 used to cross a major body of water in the US together twice, as those two used to have a concurrency on the Poplar Street Bridge over the Mississippi River, as well as the Bay Bridge pictured above.
Quote from: SkyPesos on August 13, 2021, 11:03:11 PM
^ Interesting that there used to be three cities with both US 40 and US 50 (considering that they're both x0), San Francisco, Kansas City and St Louis. Also that US 40/50 used to cross a major body of water in the US together twice, as those two used to have a concurrency on the Poplar Street Bridge over the Mississippi River, as well as the Bay Bridge pictured above.
US x0's had a penchant for multiplexing with each other: 20 & 30 through western Idaho, 30 & 40 with a functional eastern common terminus at Atlantic City, 40 & 50 as cited above, 60 & 70 in AZ and CA, with the infamous "triplex" of 60/70/80 in greater Phoenix, followed by 70 & 80 in southern NM. While US 90 originally ended at US 80, it was otherwise "free of involvement" with the other X0's. That left US 10 as the only x0 that never intersected with another x0!
Quote from: SkyPesos on August 13, 2021, 11:03:11 PM
^ Interesting that there used to be three cities with both US 40 and US 50 (considering that they're both x0), San Francisco, Kansas City and St Louis. Also that US 40/50 used to cross a major body of water in the US together twice, as those two used to have a concurrency on the Poplar Street Bridge over the Mississippi River, as well as the Bay Bridge pictured above.
Don't forget that the two routes (40 and 50) bounced off each other at the edge of downtown/midtown Sacramento for some time as well! Basically around where N Street and 15th Street intersect (which also was the historic start of the 99W/99E split).
Also for a good 20 years, US 40 and 50 were concurrent between West Wendover and the Salt Lake City area. That wasn't in the original plan, but the road across the deserts between Ely and Delta was in terrible shape at the time.
A new, better road between Ely and Delta was built by the early 1950s, and US 50 was moved to that ... but an Alternate US 50 was designated at that time along the old 50 alignment through Salt Lake, still concurrent with 40 between Wendover and Salt Lake. Alt 50 lasted through the mid-1970s, when it was decommissioned along with US 40 west of its I-80 junction near Park City.