US 70's insane extension to California

[Max Rockatansky]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?

Arizona still has some long overlaps like AZ 77/US 60.  US 60/US70 were a total overlap west of Globe.  The highway system basically was forced to clean up after California renumbered during 1964. 

[sparker]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?

Arizona still has some long overlaps like AZ 77/US 60.  US 60/US70 were a total overlap west of Globe.  The highway system basically was forced to clean up after California renumbered during 1964. 

Since all of the major desert-bound radial routes from L.A./S.D. eastward were included in the Interstate System, CA's post-'64 "one route/one number" edict meant that if AZ and NV didn't cooperate, their signed US stretches (even multiplexing over and Interstate) would simply vanish at the CA state line.  Of course, lags in CA Interstate construction dragged the process of field U.S. highway decommissioning out several more years.  But eventually AZ not only followed CA's lead but outstripped it -- while keeping some aspects of the original US system (such as US 60 west of Phoenix) that CA would have deleted and replaced with state routes.  But they also added routes after CA's big move (the US 93 extension to Wickenburg and US 160 across the NE reaches of the state), so their overall policies toward US highways is inconsistent at best.  I guess a few years down the line we'll see if US 93 ceases to exist in the state when I-11 is fully developed. 

[usends]

...they also added routes after CA's big move (the US 93 extension to Wickenburg and US 160 across the NE reaches of the state), so their overall policies toward US highways is inconsistent at best.

I don't see those two extensions as inconsistencies: one had nothing to do with parallel interstates, and the other one was only indirectly related.  US 93 had to be extended to Wickenburg or else it would've had a dangling end (because US 89 had been decommissioned).  US 160 across the Navajo reservation was a replacement for the US 164 designation (which in turn had been established to unify a relatively new highway serving a previously remote region spanning three states). 

The only inconsistency I see in Arizona's interstate-era designation changes was the fact that they kept US 60 between Phoenix and Brenda Jct. (instead of changing it to a state route, like they did with AZ 79, 80, 85, and 89).

[brad2971]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?

Arizona still has some long overlaps like AZ 77/US 60.  US 60/US70 were a total overlap west of Globe.  The highway system basically was forced to clean up after California renumbered during 1964. 

Since all of the major desert-bound radial routes from L.A./S.D. eastward were included in the Interstate System, CA's post-'64 "one route/one number" edict meant that if AZ and NV didn't cooperate, their signed US stretches (even multiplexing over and Interstate) would simply vanish at the CA state line.  Of course, lags in CA Interstate construction dragged the process of field U.S. highway decommissioning out several more years.  But eventually AZ not only followed CA's lead but outstripped it -- while keeping some aspects of the original US system (such as US 60 west of Phoenix) that CA would have deleted and replaced with state routes.  But they also added routes after CA's big move (the US 93 extension to Wickenburg and US 160 across the NE reaches of the state), so their overall policies toward US highways is inconsistent at best.  I guess a few years down the line we'll see if US 93 ceases to exist in the state when I-11 is fully developed. 

I really do not understand why ADOT, instead of having US64 end at Teec Nos Pos, doesn't have US64 take over US160 from that junction, piggy back onto US89 south, then take over the current AZ64 routing all the way to Williams at I-40.

[Max Rockatansky]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?

Arizona still has some long overlaps like AZ 77/US 60.  US 60/US70 were a total overlap west of Globe.  The highway system basically was forced to clean up after California renumbered during 1964. 

Since all of the major desert-bound radial routes from L.A./S.D. eastward were included in the Interstate System, CA's post-'64 "one route/one number" edict meant that if AZ and NV didn't cooperate, their signed US stretches (even multiplexing over and Interstate) would simply vanish at the CA state line.  Of course, lags in CA Interstate construction dragged the process of field U.S. highway decommissioning out several more years.  But eventually AZ not only followed CA's lead but outstripped it -- while keeping some aspects of the original US system (such as US 60 west of Phoenix) that CA would have deleted and replaced with state routes.  But they also added routes after CA's big move (the US 93 extension to Wickenburg and US 160 across the NE reaches of the state), so their overall policies toward US highways is inconsistent at best.  I guess a few years down the line we'll see if US 93 ceases to exist in the state when I-11 is fully developed. 

I really do not understand why ADOT, instead of having US64 end at Teec Nos Pos, doesn't have US64 take over US160 from that junction, piggy back onto US89 south, then take over the current AZ64 routing all the way to Williams at I-40.

Which would align it ironically over most of the historic route of AZ 64. 

[Verlanka]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?

Arizona still has some long overlaps like AZ 77/US 60.  US 60/US70 were a total overlap west of Globe.  The highway system basically was forced to clean up after California renumbered during 1964. 

Since all of the major desert-bound radial routes from L.A./S.D. eastward were included in the Interstate System, CA's post-'64 "one route/one number" edict meant that if AZ and NV didn't cooperate, their signed US stretches (even multiplexing over and Interstate) would simply vanish at the CA state line.  Of course, lags in CA Interstate construction dragged the process of field U.S. highway decommissioning out several more years.  But eventually AZ not only followed CA's lead but outstripped it -- while keeping some aspects of the original US system (such as US 60 west of Phoenix) that CA would have deleted and replaced with state routes.  But they also added routes after CA's big move (the US 93 extension to Wickenburg and US 160 across the NE reaches of the state), so their overall policies toward US highways is inconsistent at best.  I guess a few years down the line we'll see if US 93 ceases to exist in the state when I-11 is fully developed. 

I really do not understand why ADOT, instead of having US64 end at Teec Nos Pos, doesn't have US64 take over US160 from that junction, piggy back onto US89 south, then take over the current AZ64 routing all the way to Williams at I-40.

Probably since there was already a US highway on that stretch to begin with.

[Max Rockatansky]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?

Arizona still has some long overlaps like AZ 77/US 60.  US 60/US70 were a total overlap west of Globe.  The highway system basically was forced to clean up after California renumbered during 1964. 

Since all of the major desert-bound radial routes from L.A./S.D. eastward were included in the Interstate System, CA's post-'64 "one route/one number" edict meant that if AZ and NV didn't cooperate, their signed US stretches (even multiplexing over and Interstate) would simply vanish at the CA state line.  Of course, lags in CA Interstate construction dragged the process of field U.S. highway decommissioning out several more years.  But eventually AZ not only followed CA's lead but outstripped it -- while keeping some aspects of the original US system (such as US 60 west of Phoenix) that CA would have deleted and replaced with state routes.  But they also added routes after CA's big move (the US 93 extension to Wickenburg and US 160 across the NE reaches of the state), so their overall policies toward US highways is inconsistent at best.  I guess a few years down the line we'll see if US 93 ceases to exist in the state when I-11 is fully developed. 

I really do not understand why ADOT, instead of having US64 end at Teec Nos Pos, doesn't have US64 take over US160 from that junction, piggy back onto US89 south, then take over the current AZ64 routing all the way to Williams at I-40.

Probably since there was already a US highway on that stretch to begin with.

Two actually, everyone forgets about US 164. 

[sparker]

If Arizona doesn't like overlaps, why was so much of AZ 93 a useless overlap?

Arizona still has some long overlaps like AZ 77/US 60.  US 60/US70 were a total overlap west of Globe.  The highway system basically was forced to clean up after California renumbered during 1964. 

Since all of the major desert-bound radial routes from L.A./S.D. eastward were included in the Interstate System, CA's post-'64 "one route/one number" edict meant that if AZ and NV didn't cooperate, their signed US stretches (even multiplexing over and Interstate) would simply vanish at the CA state line.  Of course, lags in CA Interstate construction dragged the process of field U.S. highway decommissioning out several more years.  But eventually AZ not only followed CA's lead but outstripped it -- while keeping some aspects of the original US system (such as US 60 west of Phoenix) that CA would have deleted and replaced with state routes.  But they also added routes after CA's big move (the US 93 extension to Wickenburg and US 160 across the NE reaches of the state), so their overall policies toward US highways is inconsistent at best.  I guess a few years down the line we'll see if US 93 ceases to exist in the state when I-11 is fully developed. 

I really do not understand why ADOT, instead of having US64 end at Teec Nos Pos, doesn't have US64 take over US160 from that junction, piggy back onto US89 south, then take over the current AZ64 routing all the way to Williams at I-40.

Probably since there was already a US highway on that stretch to begin with.

Two actually, everyone forgets about US 164. 

IIRC, US 164 existed during the time when US 64 was gradually being extended west from Taos, NM; I believe it had gotten to Farmington and (then) US 550 about the time that the decision was made to change the number to US 163 (one of the weirder SCOURN moves).  And US 160 still extended northwest from Cortez, CO to US 6/50/I-70 via Moab, UT, before the hyperextended US 191 was commissioned.  The US highway network in that area looked like a shell game for a while -- and to some extent, still does!  Personally, I would support the supplanting of US 160 and all of AZ 64 with US 64 -- actually give that almost-transcontinental route a real place to go (like the Grand Canyon).  And bring back US 164 while one is at it -- it'd be most appropriate.  I'd elaborate on other options, but this isn't Fictional!  In any case, I don't think we've seen the end of route renumbering in these parts!   

[US 89]

IIRC, US 164 existed during the time when US 64 was gradually being extended west from Taos, NM; I believe it had gotten to Farmington and (then) US 550 about the time that the decision was made to change the number to US 163 (one of the weirder SCOURN moves).  And US 160 still extended northwest from Cortez, CO to US 6/50/I-70 via Moab, UT, before the hyperextended US 191 was commissioned.

US 164 never really came that close to US 64 and probably was numbered out of respect for the aforementioned AZ 64, which most of US 164 had replaced. During the brief time 164 existed, US 64 dipped south at Taos along what is now NM 68 and US 84/285 to a terminus in Santa Fe. US 64 wasn't rerouted to Farmington until 1972, two years after US 164 had been absorbed into an extension of US 160.

The area's major renumbering that occurred in 1970 mainly happened because the road from Kayenta to Monticello was added to the US highway system, creating more of a continuous north-south US route corridor through southeast Utah and northeast Arizona. That was when US 160 was removed from Utah and sent southwest from Cortez to US 89 at Tuba City, replacing US 164. The road from Cortez to Monticello became an extension of US 666 (which previously had ended in Cortez), while the remainder of ex-160 from Monticello north to Crescent Junction became part of the greater Kayenta-Crescent Junction route.

Of course, that new north-south route needed a number. According to this USEnds blog post, the original number assigned to that corridor was 164. But the plan that was ultimately approved by AASHO replaced that with 163. I'm not sure where I read this, but I've heard that change may have been made because somebody involved in the decision-making processes thought the odd/even number/direction guideline applied to 3dus routes (it does not).

US 191 wasn't extended south from Yellowstone until 1982, and after a couple years, all US 163 signage north of Bluff (its junction with 191) had disappeared. But UDOT didn't officially apply to AASHTO to truncate US 163 to Bluff until 2008. That was approved...but UDOT's route inventory files still have US 163 extending all the way up to Crescent Junction.

[TravelingBethelite]

Just imagine what the multiplex of 1, 9, and 30 would be called... 1930? And if 22 were put on the route of 139 and the surface portion of 78, then it could possibly be 1-9-22-30, which would just be, pardon mon français, a clusterfuck.

Yeah, I suppose four US routes running together would be a bit of a mouthful.

Well, look at all that traffic! That's what happens when route concurrency is allowed to run rampant :-)

Or the multiplex of 12-14-18-151 on the Beltline. https://www.google.com/maps/@43.0373377,-89.3895835,3a,75y,247.95h,79.06t/data=!3m6!1e1!3m4!1swxnqzeNQr0916j1MwCvSsA!2e0!7i16384!8i8192?hl=en

...or the multiplex of US 56, 64, 385, and 412 west of Boise City, OK

https://www.google.com/maps/@36.6985555,-102.5531509,3a,75y,97.9h,92.21t/data=!3m6!1e1!3m4!1sAr6h6P3I1kjWGXJgqm_S3A!2e0!7i3328!8i1664

[sparker]

Just imagine what the multiplex of 1, 9, and 30 would be called... 1930? And if 22 were put on the route of 139 and the surface portion of 78, then it could possibly be 1-9-22-30, which would just be, pardon mon français, a clusterfuck.

Yeah, I suppose four US routes running together would be a bit of a mouthful.

Well, look at all that traffic! That's what happens when route concurrency is allowed to run rampant :-)

Or the multiplex of 12-14-18-151 on the Beltline. https://www.google.com/maps/@43.0373377,-89.3895835,3a,75y,247.95h,79.06t/data=!3m6!1e1!3m4!1swxnqzeNQr0916j1MwCvSsA!2e0!7i16384!8i8192?hl=en

...or the multiplex of US 56, 64, 385, and 412 west of Boise City, OK

https://www.google.com/maps/@36.6985555,-102.5531509,3a,75y,97.9h,92.21t/data=!3m6!1e1!3m4!1sAr6h6P3I1kjWGXJgqm_S3A!2e0!7i3328!8i1664

Back about 1959, five routes were signed on the N-S freeway through San Bernardino, CA between 5th Street and Highland Ave:  I-15, US 66, US 91, US 395, and SSR 18.  Close behind was the first freeway segment on that route between Palm Springs and Indio: I-10, US 60, US 70, and US 99.  Situations like that were the catalyst behind the movement of "one route/one number" that instigated the 1964 state renumbering effort.

[mrsman]

Just imagine what the multiplex of 1, 9, and 30 would be called... 1930? And if 22 were put on the route of 139 and the surface portion of 78, then it could possibly be 1-9-22-30, which would just be, pardon mon français, a clusterfuck.

Yeah, I suppose four US routes running together would be a bit of a mouthful.

Well, look at all that traffic! That's what happens when route concurrency is allowed to run rampant :-)

Or the multiplex of 12-14-18-151 on the Beltline. https://www.google.com/maps/@43.0373377,-89.3895835,3a,75y,247.95h,79.06t/data=!3m6!1e1!3m4!1swxnqzeNQr0916j1MwCvSsA!2e0!7i16384!8i8192?hl=en

...or the multiplex of US 56, 64, 385, and 412 west of Boise City, OK

https://www.google.com/maps/@36.6985555,-102.5531509,3a,75y,97.9h,92.21t/data=!3m6!1e1!3m4!1sAr6h6P3I1kjWGXJgqm_S3A!2e0!7i3328!8i1664

Back about 1959, five routes were signed on the N-S freeway through San Bernardino, CA between 5th Street and Highland Ave:  I-15, US 66, US 91, US 395, and SSR 18.  Close behind was the first freeway segment on that route between Palm Springs and Indio: I-10, US 60, US 70, and US 99.  Situations like that were the catalyst behind the movement of "one route/one number" that instigated the 1964 state renumbering effort.

While I understand CA's motivation for 1964, I think they used a hatchet when only a surgeon's scalpel would have been necessary.  It probably did not make much sense for US 99 to exist south of Wheeler Ridge and N/S US 99 along the largely E-W LA-Indio corridor adds to confusion, but there was no need to totally demote US 99 to CA 99.  It should have retained its US status from Wheeler Ridge north to Canada.  As discussed by others upthread, US 70, absent a unique route to the beach, had no good reason to even exist West of Globe, so that can be deleted in CA.  That would leave a much more manageable I-10/US 60 routing from Beaumont to Arizona, which also would have informed drivers of the Pomona Fwy as being part of a national network (and not just a local CA-60 route).  A multiplex of two routes, even for a few hundred miles, isn't confusing, and is quite common around the country.

The routings along I-15 were a little more complicated and have an interesting history.  With the hindsight of how the routings actually came out (especially the extension of I-15 proper through Eastern Ontario and Corona to San Diego), it would make sense to keep all of those routes along the stretch, except for US 91.  So initially, US 395 and CA-18 join in Riverside and march north.  The roadway adds I-15 after passing I-10, adds US 66 at 5th street, drops CA-18 two miles later at Highland, and then drops US 395 in Hesperia to continue as I-15/US 66 all the way to Barstow.  But with the extension of I-15 to San Diego, it made sense to truncate US 395 in Hesperia.  And with the construction of the I-15 bypass in Ontario, it would make sense to have US 66 follow that routing.  This would then mean, that the only multiplexing in the area would be: the short (US) 60/215 that exists in Riverside; CA-18/I-215 from Riverside to the CA-259 fwy split; and I-15/US 66 between the current 15/210 interchange and Barstow.  These are much more manageable multiplexes and would not have led to widespread confusion.

[CA-91 west of Riverside would be part of CA-18, CA-259 would also be part of CA-18.]

[sparker]

^^^^^^^^^^^^
It's possible that DOH -- and later Caltrans -- may have made an exception to their non-multiplex post-'64 policy and allowed US 99 to be co-signed with I-5 as far south as Red Bluff, where it would diverge -- but almost certainly the 99E/W split would have been jettisoned in favor of the route currently occupied by CA 99.  But the mid-60's decision by OR to decommission US 99 in that state probably tipped the scales toward recasting the US route as a state highway.  US 99 signage hung on on the Wheeler Ridge-Sacramento section until the fall of 1966, while US 99W signage north of I-80 persisted until I-5 was completed in the Sacramento Valley about 1973; US 99 signage also could be found until the mid-70's on the last remaining 2-lane sections of the old road until about 1975, when the Anderson Grade section bypassing now-CA 263 was completed.  But once I-5 was effectively done (the Sacramento Canyon expressway segment, not fully completed until 1992, notwithstanding), US 99 shields were also gone. 

While nostalgia/historical buffs may decry any lack of effort on the part of Caltrans to recommission US 99 over CA 99, it wouldn't really fulfill any functional or navigational purpose; CA 99 has been, more or less, where it has since the green spades were erected over its full length in 1966 -- now almost 55 years ago.  All that being said -- I'd welcome the posting of prominent Historical US 66 and Historical US 99 signage over those sections of the original highway that were physically overlaid by the freeway.  In the case of US 66, that would include the state line west to the original alignment, Ludlow west to Newberry Springs, and Victorville to just below CA 138 (the Cleghorne exit).  The original surface alignment is extant, continuous, and accessible elsewhere.  In the case of US 99, the "business routes" through the various cities -- where possible -- would be signed as part of the historical alignment, as well as the intervening freeway sections of CA 99.  If by chance I-7 or I-9 ever supplants CA 99 in the Valley below Sacramento or Stockton, the historical signage would be even more significant, as it would preserve the number itself (Maybe the new US 99 Historical Society can take up this concept).