Things you've always wanted to ask, but think it's not worth making a topic for

[agentsteel53]

I-50 and I-60 were skipped intentionally in the original plan, because it was decided that they might cause confusion by being too close to US-50 and US-60. None of the north-south route numbers were skipped because they were all needed to cover the wide expanse of the nation. Of course, we have several cases of interstates added later that are very close to US routes with the same numbers.

I think that a set of lucky coincidences allowed the planners to get away with not overtly skipping some odd numbers in the 5x-6x range.

* north-south routes are usually shorter than east-west, so one can get away with two 45s fairly close to each other (and two 49s with just a bit of fudging on the Arkansas extension).
* US-59 is somewhat farther west than the grid would dictate, and I-59 heads somewhat further east.
* there is no US-55 and was no US-57 at the time.  (also there is no US-47.)

that said, there were some numbers definitely skipped in that range: there is no I-47, 51, 53, 61, or 63, which are really the ones that would likely coincide with US numbers.  (again, there is no US-47.  I wonder what the planners have against that number.)

[NE2]

Another reason why none of the north-south ones were skipped is because the major US routes end in 1 and the major Interstates end in 5. For east-west routes, both major Interstates and major US routes end in 0, causing conflict.

Most numbers ending in 5 were a second run of major U.S. Routes. What saved the day was US 55's early elimination and the relative narrowness of Midwestern states (if Illinois were as wide as it's tall, it might have both I-65 and US 65).

[Zmapper]

How do they get the arrow shape in traffic lights, especially before the dot-like LED lights became common?

My first guess would be an opaque filter, but that would seemingly provide a slight intensity gradient progressing inward. Either the intensity gradient exists and I don't notice it, or another method is used.

[Brandon]

Mackinac
Charlevoix
Cheboygan
Sault Sainte Marie
Marquette
Joliet (old Frog - now spelled Joliette)
La Salle

I'm not from the region, so I'm sure most of these are different from what locals would say, but I pronounce those names respectively:
Mack-in-ack

Mack-in-awe  The "c" at the end is slient.

Shar-le-vwah

Shar-leh-voi

Sheh-boy-gone

Sheh-boi-gahn

Salt Saint Marie

Soo Saint Marie  Commonly called "The Soo" for short.

Mar-kett

Yep.

Jo-lee-et

Yep.

Luh Sall (rhyming with "stall"")

Lah Sal (sounds like Sal)

[theline]

Two more interesting facts about the Michigan francophone place names:

Mackinac is the proper spelling of the straits, island, park, and nearly everything related, except for nearby Mackinaw City (pronounced the same). There's always one oddball.

Sault Sainte Marie is home to the famous Soo Locks, which enable ocean-going ships to climb from Lake Huron to Lake Superior. Wikipedia claims they are sometimes spelled "Sault Locks" though I've never seen the spelling elsewhere.

[sandiaman]

I rented a house  to a lady     and her elderly mother whose family owned  the newspaper  in Newport News.  I asked her if  they called  the paper the Newport News News.  She  didn't think it  was   funny.   Even she didn't know where the  city got its  name.

[roadman65]

Why does I-19 end in Downtown Nogales instead of terminating at the AZ 189 & Mexico 15D border crossing?  I would think that would be more of a logical place then the current place where you have to round the block to get from I-19's southern terminus to the entry point of current.

[sammi]

Sault Sainte Marie

I always thought it was pronounced like "so", and that every weather reporter pronounced it wrong.

[DaBigE]

How do they get the arrow shape in traffic lights, especially before the dot-like LED lights became common?

My first guess would be an opaque filter, but that would seemingly provide a slight intensity gradient progressing inward. Either the intensity gradient exists and I don't notice it, or another method is used.

Your guess is correct: http://www.tapcosignal.com/sa_poly.html ...item #16 near the bottom of the page. I have a couple of those masks--they [mine] are solid metal painted black. The reflector dish around the bulb does a nice job of evenly distributing the light.

[CtrlAltDel]

Sault Sainte Marie

I always thought it was pronounced like "so", and that every weather reporter pronounced it wrong.

In French it is.

[cpzilliacus]

are "colour", "Marlborough", etc close to actual Latin?  as in, should I expect to see "COLOVR" carved into some Roman piece of architecture?

COVNTY:

http://commons.wikimedia.org/wiki/File:Patch_of_the_Prince_Georges_County,_Maryland_Police_Department.png

[agentsteel53]

are "colour", "Marlborough", etc close to actual Latin?  as in, should I expect to see "COLOVR" carved into some Roman piece of architecture?

COVNTY:

http://commons.wikimedia.org/wiki/File:Patch_of_the_Prince_Georges_County,_Maryland_Police_Department.png

yes, but the spelling of "county" doesn't vary between American and British English.  it's not like one spells it "conty" (or, oh dear, eliminates the other vowel instead).

[NE2]

yes, but the spelling of "county" doesn't vary between American and British English.  it's not like one spells it "conty" (or, oh dear, eliminates the other vowel instead).

Apparently I was living life on the dangerous side today.  I pulled over to get this pic (on my phone camera):

[realjd]

Here's one: what are those loops of wire that are always next to a traffic light hanger on span wire installations? Why don't they just cut the power cables to length?

[agentsteel53]

Here's one: what are those loops of wire that are always next to a traffic light hanger on span wire installations? Why don't they just cut the power cables to length?

I would guess that it's there in case they need to lengthen the wire by a small amount.  moving the signals on the mast a bit, maybe?

[J N Winkler]

Why does I-19 end in Downtown Nogales instead of terminating at the AZ 189 & Mexico 15D border crossing?  I would think that would be more of a logical place then the current place where you have to round the block to get from I-19's southern terminus to the entry point of current.

This question is difficult to answer definitively without access to the original planning documentation, which--as far as I know--is not available online.  However, it is possible to form an educated guess by looking at historic topographic maps of the area.

The lowest and flattest part of Nogales is the area along present Business 19 north of the border/Mex. 15 south of the border.  This has nearly all of the population.  There are rugged hills to the west; both I-19 and the Mex. 15D freeway have many steep rock cuts.  SR 189 has fewer, but only because it essentially follows a hilltop routing.

At the time I-19 was finished (early 1970's), the Mex. 15D freeway, which runs between the Arizona SR 189 border crossing and Mex. 15 south of Nogales, did not exist.  The connection was made via a surface street (currently four lanes, divided in some places but not others; the 1981 USGS 7.5' topographic map covering the Nogales area implies it was then two-lane) which Google Maps shows as Periférico Luís Donaldo Colosio Murrieta.  The Mex. 15D relocation to the west (operated as a corredor fiscal with no exits between the border and the customs station) opened around 2000, at around the same time US Customs and Arizona DOT redeveloped the SR 189 Mariposa port of entry into a large facility oriented primarily at handling commercial vehicles.

On the Sonora side, nearly all of the development in Nogales is east of Periférico Colosio.  On the Arizona side, the SR 189 corridor was (and to an extent still is) very bare, and Nogales as a whole has very little development that is not within a mile of SR 89/Business 19.  The built-up area peters out very rapidly north of the SR 83 grade separation about a mile south of SR 189.

So, at the time I-19 was being planned and designed, routing it along present SR 189 would have entailed limiting Nogales to just one local service exit, for SR 189 itself, which is quite far out of town and remote from the downtown border crossing.  From the standpoint of international traffic, such a routing would have skirted the built-up parts of Nogales on both sides of the border, but would have entailed connecting an Interstate-quality facility with what was then a much inferior counterpart south of the border.  On the other hand, the routing actually built gives Nogales three local service exits in addition to SR 189 (Western Ave., International St., and the terminus) and allows residents on the American side to benefit from an access-controlled facility within easy reach of the population core.  It is awkward to have to go along three sides of a square to reach the border crossing from I-19, but given how the latter almost shaves the border fence, this was probably necessary in order to inject southbound I-19 traffic into the border queue at the back.

[doogie1303]

How do they get the arrow shape in traffic lights, especially before the dot-like LED lights became common?

My first guess would be an opaque filter, but that would seemingly provide a slight intensity gradient progressing inward. Either the intensity gradient exists and I don't notice it, or another method is used.

Your guess is correct: http://www.tapcosignal.com/sa_poly.html ...item #16 near the bottom of the page. I have a couple of those masks--they [mine] are solid metal painted black. The reflector dish around the bulb does a nice job of evenly distributing the light.

I always thought it was masked out on the lens with black paint, learn something new everyday.

[getemngo]

Two more interesting facts about the Michigan francophone place names:

Mackinac is the proper spelling of the straits, island, park, and nearly everything related, except for nearby Mackinaw City (pronounced the same). There's always one oddball.

Yep, regardless of spelling, it's always pronounced "Mackinaw." But there is another oddball. Old US 2 from St. Ignace north is named Mackinac Trail. Portions of old US 31 and old US 131 in the Lower Peninsula are named Mackinaw Trail.

Sault Sainte Marie is home to the famous Soo Locks, which enable ocean-going ships to climb from Lake Huron to Lake Superior. Wikipedia claims they are sometimes spelled "Sault Locks" though I've never seen the spelling elsewhere.

Also, note that Sault Ste Marie is adjacent to Soo Township.

[Sykotyk]

Why does I-19 end in Downtown Nogales instead of terminating at the AZ 189 & Mexico 15D border crossing?  I would think that would be more of a logical place then the current place where you have to round the block to get from I-19's southern terminus to the entry point of current.

Probably similar to I-35 ending shortly before the international bridge in Laredo. The border crossing already existed prior to the interstate. At the time, it was probably sparsely populated and not in desperate need of a freeway access point to Mexico, which most certainly didn't have anything close to an interstate/freeway at that time. The freeway simply got you as close as necessary. No different than some hackjob freeway interchanges on an upgraded portion that utilize the old interchange and route the freeway around: US35 and I-71, US63 and I-70, etc.

[J N Winkler]

Probably similar to I-35 ending shortly before the international bridge in Laredo. The border crossing already existed prior to the interstate. At the time, it was probably sparsely populated and not in desperate need of a freeway access point to Mexico, which most certainly didn't have anything close to an interstate/freeway at that time. The freeway simply got you as close as necessary.

That explanation doesn't work, since border crossings existed for both SR 189 and US 89 in the Nogales area at the time I-19 was being planned and designed.  You could argue that it would have been better to route I-19 along SR 189 instead because that alignment is less hilly (thus cheaper to build), and less populated on both sides of the border, which exposes cross-border traffic to less congestion delay.  (The US 89 border crossing would have had more lanes, but also more traffic congestion since it feeds directly into downtown Nogales, Sonora.)  Given these considerations, why choose a new-terrain location for I-19 that is both more expensive to build and leads to more congestion on the Mexican side?

My theory (sketched out upthread) is that the designers placed more of a priority on local traffic service in Nogales, which is reasonable given that (1) relatively little traffic actually crosses the border, and (2) delays clearing immigration and customs mean a freeway makes relatively little difference to the total time required to transit the US/Mexico border zone.  I-19, as ultimately built, reaches directly into downtown Nogales and has four local-service exits, as opposed to just one exit far out of town if the SR 189 corridor had been chosen.

[NE2]

That explanation doesn't work, since border crossings existed for both SR 189 and US 89 in the Nogales area at the time I-19 was being planned and designed.

Are you sure? The first entry for the current SR 189 west of I-19 is from 1971, and SR 189 is not on the 1971 official.

[J N Winkler]

That explanation doesn't work, since border crossings existed for both SR 189 and US 89 in the Nogales area at the time I-19 was being planned and designed.

Are you sure? The first entry for the current SR 189 west of I-19 is from 1971, and SR 189 is not on the 1971 official.

Actually, after looking more closely in different sources, I see the facts offer more support for Sykotyk's theory than I had originally thought, so I apologize for speaking slightingly of it.

Here is what I have been able to determine:

*  Azhighwaydata.com gives a date (probably the title sheet signature date) of 1969 for "Nogales Interstate Freeway," which is presumably the length of I-19 from its southern terminus to approximately the SR 189 interchange.  Azhighwaydata.com gives a date of 1970 for the signing along this length, which was done under a separate contract (captioned "Nogales-Otero TI") and extended from the southern terminus north to Peck Canyon Road (Exit 20).  My guess is that this length opened to traffic around 1971 or 1972.

*  An ADOT publication, Arizona-Sonora Border Master Plan (2013), gives short histories of the various land ports of entry.  DeConcini (present SR 89/Business 19 crossing in downtown Nogales) is described as "more than 100 years old."  Mariposa (SR 189 crossing) opened to commercial vehicles in 1976 and passenger cars in 1978.

The USGS 7.5" quadrangle covering this area dates from 1981 and shows both ports of entry in operation, with Mex. 15 routed along what is now Periférico Luís Donaldo Colosio, skirting built-up Nogales, Sonora to the west and hooking up with SR 189 at the border.

My interpretation, based on this evidence, is that there was probably a plan to create a new border crossing to the west of Nogales (DeConcini was already landlocked back then) around the time the I-19 alignment around Nogales was being chosen, but I-19 was routed along its present track rather than what is now SR 189 partly for better local service and partly also because DeConcini was, at the time, the bird in hand.  There may also have been a plan (subsequently abandoned) to use the Mariposa/Nogales III crossing only for commercial vehicles.

[Pete from Boston]

What's the point of the new red or green solid circles in signs referencing traffic lights, like "left turn yield on green" or "no turn on red"?

Few who can't read understand the word "red" is going to figure out what the rest of the sign says, so that can't be it.

[formulanone]

My guess is that someone is more likely to read it if there's something nearby and similar. Kind of like an If (you see this) -Then (do this) statement?

[realjd]

What's the point of the new red or green solid circles in signs referencing traffic lights, like "left turn yield on green" or "no turn on red"?

Few who can't read understand the word "red" is going to figure out what the rest of the sign says, so that can't be it.

It's to indicate that the sign refers to the green ball, not the green arrow. Leaving is just saying "left turn yield on green" can be ambiguous.

The color also helps draw attention to the sign.