State or US Highways with little or no use.

[Mapmikey]

In terms of low traffic volumes, there's the matter of U.S. 250 in Highland County, Virginia. 

VDOT apparently likes to refer to it as Highland Turnpike, but I have also seen it called Mountain Turnpike (WVDOT calls it the Staunton-Parkersburg Turnpike).  2016 AAWDTs range from 360 at the border with Pocahontas County, West Virginia (about 13 miles west of the county seat of Monterey) to 1200 at the Augusta County border). Rugged and beautiful country, and probably should IMO remain  a Virginia primary system highway, but not exactly overloaded with traffic.

WVDOT shows a count from 2015 of about 341 on their side of the border (close enough IMO to the Virginia published count of 360).

US 220's state line AAWDT north of Monterey is 690 and VA 84's state line AAWDT southwest of Monterey is 200.  Highland County's population is under 2200 and is one of a handful of Virginia counties without a stoplight...

[silverback1065]

ok so this begs the question: what is the lowest AADT for any numbered highway in the US?

[Max Rockatansky]

ok so this begs the question: what is the lowest AADT for any numbered highway in the US?

I'm pretty certain it's US 191 on the Coronado Trail in regards to US Route.   When I clinched CA 229 the local Caltrans crew preforming maintenance told me the one-lane part of the route only got 3-4 cars a day south of Creston to CA 58. 

[US 89]

The lowest AADT on a Utah state-maintained highway is 30, on UT-124 between Columbia and the Horse Canyon Mine.

[barcncpt44]

I would say AL 281 has very low traffic counts, in fact the stretch between US 431 and US 78 only has 80-90 cars AADT.  And the stretch south of Cheaha State Park has only 100 AADT.  In fact the whole route has less than 500 AADT.

[corco]

If we're talking low AADTs, WYO 77 has an AADT around 24 - it's an old 22 mile long alignment of WYO 487 that connects to it on both ends with nothing along the route that anybody would conceivably need to access, except maybe some hunting spots. It's not faster than just staying on 487, though you can drive as fast as you want which could make it faster - limited only by the rapidly deteriorating pavement.

For "major" routes, a healthy chunk of Montana 200 (part of MSR 200 and the best through route across central Montana) from Grass Range all the way to Sidney (235 miles) has around 500 cars per day on the entire stretch. That doesn't beat the Coronado Trail, but 200 in that part of Montana is a significantly more important highway than 191 in that part of Arizona.

[wxfree]

ok so this begs the question: what is the lowest AADT for any numbered highway in the US?

This is an interesting question.  Texas has some single-digit and 10 counts on various pieces of road in various years.  In the most recent data, for 2016, RM 2810 has a count of 9 near the end of the pavement before it turns into a gravel road.  In the past decade, it's been as high as 21.

The lowest number on a non-bypassed through road I can find is 22 on RM 2886, between I-10 and RM 2400.  Also notable is a count of 43 on SH 349, because it's a primary state highway and because it's between I-10 and US 90 (it's also a beautiful drive).  The lowest maximum count I see is along Loop 293, which serves as a business route for I-10 through Bakersfield.  Its two counts, one on each side of town, are 22 and 32.  The lowest maximum I found for an entire non-bypassed through road is 70 on RM 2400 (which is also a nice drive).  It's a 40-mile road where you can sometimes drive from one end to the other without seeing another vehicle the whole time, but you do usually see one or two.

I'm pretty sure the lowest on a US Highway is 134 along US 385 between I-10 and US 90 and the lowest on an Interstate is 5,612 along I-10 east of I-20.

[Max Rockatansky]

ok so this begs the question: what is the lowest AADT for any numbered highway in the US?

I'm pretty sure the lowest on a US Highway is 134 along US 385 between I-10 and US 90 and the lowest on an Interstate is 5,612 along I-10 east of I-20.

And to think I ran into a trucker I had a hell of a time passing leaving Big Bend National Park via US 385 back 2013. 

Incidentally I found the article citing the traffic count on US 191/Coronado Trail as 81 vehicles a day. 

http://www.eacourier.com/copper_era/news/adot-engineer-it-s-time-for-a-serious-discussion-on/article_a5141af0-c979-11e7-8a80-3f32813c804c.html

[Eth]

ok so this begs the question: what is the lowest AADT for any numbered highway in the US?

Getting into the state-by-state numbers...yeah, good luck looking this one up for Georgia. GDOT's traffic count tool certainly has the data, but searching it is a nightmare. It's probably unlikely there's an AADT under 100 anywhere in our state highway system, though.

[wxfree]

And to think I ran into a trucker I had a hell of a time passing leaving Big Bend National Park via US 385 back 2013. 

The 2013 counts south of US 90 were even lower than the number I reported, below 100.  In 2016 they were around 200.  But nearly all of that traffic is driven by park visitation, which is highly variable.  During the spring break weeks and the winter holidays visitation, and traffic, go way up.  On an annualized basis, that's compensated for by very low traffic for most of the year.

[hotdogPi]

Is there any use for NH 9A, 11C, 11D, 16A (both), 16B, 25B, 28A (northern), 101E, 103B, 110A, 110B, 115A, or 115B?

[oscar]

I'm pretty sure the lowest on a US Highway is 134 along US 385 between I-10 and US 90 and the lowest on an Interstate is 5,612 along I-10 east of I-20.

I-15 in Idaho and Montana between Idaho Falls and Butte might be lower. Much of that segment was a Super-2 for a long time.

Some of the unsigned Alaska Interstates have three-digit AADTs, especially I-A1 (signed as part of AK 2) between AK 5 and the Canadian border. In 1994 on that stretch, I and another driver pulled over to watch a bald eagle perched on a tree, hoping it would take flight so we could take photos (no luck). During the 15 minutes we were there, not a single vehicle passed in either direction.

[wxfree]

Just to be clear, my numbers are limited to Texas, although I'm sure the 9 is pretty strong competition in any state.  I'm familiar with TxDOT's web site, and it's a pretty good web site so I can usually find what I want, which is why I was able to find such detailed information.

If you want the Texas numbers, you can use the statewide planning map, but you have to zoom in to small areas to see them.  It's easier to look at the PDF maps.  On this page you can pick a year and then pick a district.  I've noticed a few count points on the planning map that don't appear in the PDF maps; I don't know how common that is.

http://ftp.dot.state.tx.us/pub/txdot-info/tpp/traffic_counts/

[silverback1065]

Indiana SR 166 has an AADT of 38 this highway just dead ends, so that's why

[SectorZ]

Is there any use for NH 9A, 11C, 11D, 16A (both), 16B, 25B, 28A (northern), 101E, 103B, 110A, 110B, 115A, or 115B?

As someone who has frequently driven or ridden a bike on all of those...

Yes for 11C, 25B, 110A, and 115A
No for 9A, 11D, 16A (both), 16B, 28A (northern) 101E, 103B, 110B, 115B (also 115B may or may/not exist - that's for another thread)

[silverback1065]

This is sort of related to my question: https://www.citylab.com/transportation/2018/03/americas-loneliest-roads-are-gems-hidden-in-plain-sight/555779/?utm_source=SFFB

[Beeper1]

The lowest AADT on the interstate system (at least on the major interstates) is on I-95 on its northernmost stretches in Maine.  By the time you reach Aroostock County neat the border, the AADT gets down into the 2000s.

[corco]

I-25 in Wyoming is in the 17-1800s between Casper and a bit north of Kaycee. I-90 between Sheridan WY and Gillette WY is also just a bit below 2000.

I'm pretty sure that chunk of I-25 is the lowest on interstates in the country - even lower than I-15 in Montana (which has no less than a hair under 2000 in a couple places, even up by the border).

[paulthemapguy]

Indiana SR 166 has an AADT of 38 this highway just dead ends, so that's why

This useless highway is the biggest annoyance to me, because it causes the single biggest detour in my quest to photograph all the Indiana state routes.  I basically have to sidetrack myself from Santa Claus all the way over to get it.

[silverback1065]

Indiana SR 166 has an AADT of 38 this highway just dead ends, so that's why

This useless highway is the biggest annoyance to me, because it causes the single biggest detour in my quest to photograph all the Indiana state routes.  I basically have to sidetrack myself from Santa Claus all the way over to get it.

SR 111 does the same thing just a few miles east

[roadman65]

GA 122 west of Waycross, GA.  Its more like a back road than a major highway as it gets very little use on it.

[TheHighwayMan3561]

MN 1 west of MN 89 in Beltrami County only gets 45 cars a day. I was surprised that the MN 11 dead end east of Voyageurs NP still gets 300.

[Mark68]

CO 3 in Durango. It's the former alignment of US 160/550 south and east of town, but now all it really does is service the residential areas on the east side of town--which the highway designation no longer reaches now that it's been routed to return to 160/550 on Santa Rita Dr south of town.

CO 11 near Julesburg (AADT 530). Connects to I-80 across the NE state line, but is a county road on the Nebraska side of the border. It's also less than a mile and a half in length.

[NWI_Irish96]

Indiana SR 166 has an AADT of 38 this highway just dead ends, so that's why

This useless highway is the biggest annoyance to me, because it causes the single biggest detour in my quest to photograph all the Indiana state routes.  I basically have to sidetrack myself from Santa Claus all the way over to get it.

SR 111 does the same thing just a few miles east

I've hit both on my quest to clinch all the state highways.  I'm surprised that 166 gets so little usage as there are a few businesses along the way and a town at the end.

[mrcmc888]

TN-370 is a tiny little route that serves only to connect TN-144 to TN-61, which TN-131 already did in the first place.  It's out in the middle of nowhere and everyone just takes 131 instead.

TN-1 randomly becomes signed in Sparta for a few miles before getting right back onto US 70.  Lord knows who had that idea as the short route could just as easily have been numbered something else or been a bannered US 70.

TN-266 connects Lebanon to absolutely nowhere.

TN-334 in Alcoa is a tiny pointless connector between TN-333 and 335.  It's like they slapped a state route sign on a 1 mile neighborhood road.