At-grade Interstate interactions inventory

[wxfree]

The discussion in the I-69 thread made me interested in making an inventory of at-grade interactions along I-10 in Texas.  I'll probably include I-40 soon.  If someone knows where they are in other states and wants to inventory them, this list could be moved to the general forum.

Unless otherwise noted, these examples are of officially sanctioned grade crossings.  In places, there's an unofficial frontage road (gravel, on the highway right-of way) on the side opposite the official frontage road.  This unofficial frontage road connects with many drives.  Even when these drives seem to extend to the freeway, they are not included unless there's a stop sign at the edge of the freeway, since these drives are accessible from the unofficial frontage road.  I do list some cases of apparent unofficial tolerance where it appears to be the only way to get somewhere, but my real interest is in official sanction, such as shown by signs and breaks in the barrier.  Some drives have a stop sign at the edge of the freeway, and no signs indicating an official path for a left turn.  Even though left turns may be made there, these are noted as RIRO.  Newer imagery shows cable barriers in some places, which would enforce the restriction.

Those noted as "unofficial" have no sign, but there's a drive and a gate, and no other way for vehicles to go but the freeway.  These are presumed to be unofficially tolerated RIRO.  Hudspeth County seems to have straight-up official crossings, while further east they prefer unsigned T-intersections.

I didn't include U-turns, even without prohibition signs.  There are areas with frequent unofficial U-turns, but my primary interest is in what's allowed, not what's tolerated.  Unlike the RIROs, U-turns are not the only way get somewhere.

https://www.google.com/maps/@31.196993,-105.584053,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.195424,-105.548001,206m/data=!3m1!1e3?hl=en unofficial

https://www.google.com/maps/@31.196683,-105.524101,413m/data=!3m1!1e3?hl=enThis one has a stop sign and a break in the barrier, but there's a sign that says the middle crossing is for official or emergency use only, so I call it RIRO

https://www.google.com/maps/@31.202509,-105.513466,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.212208,-105.497074,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.189292,-105.419449,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.163499,-105.318056,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.150828,-105.27527,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.1420692,-105.2458354,413m/data=!3m1!1e3?hl=en

The next two show unofficial exit and entrance ramps to access a public road from the eastbound direction.  Westbound has a frontage road.
https://www.google.com/maps/@31.1299625,-105.2044622,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.1274093,-105.1952998,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.119769,-105.170376,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.049241,-104.931322,413m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@31.046721,-104.922802,413m/data=!3m1!1e3?hl=en unofficial

https://www.google.com/maps/@31.039106,-104.902483,413m/data=!3m1!1e3?hl=en unofficial

For the next two, I link to Street View, because it shows an official sign, but there doesn't seem to be a drive any longer.
https://www.google.com/maps/@31.037607,-104.891979,3a,75y,13.52h,90t/data=!3m4!1e1!3m2!1sOYP6jnfgN1KzrJVEJxoQbg!2e0?hl=en

https://www.google.com/maps/@31.037258,-104.889648,3a,75y,17.4h,90t/data=!3m4!1e1!3m2!1sDPSogOMrQ_uMOHx-6-3cjg!2e0?hl=en

https://www.google.com/maps/@31.059152,-104.535902,413m/data=!3m1!1e3?hl=en unofficial

https://www.google.com/maps/@31.06953,-104.451068,413m/data=!3m1!1e3?hl=en unofficial

https://www.google.com/maps/@31.072996,-104.420385,413m/data=!3m1!1e3?hl=en unofficial

https://www.google.com/maps/@31.065028,-104.310828,413m/data=!3m1!1e3?hl=en unofficial

I count 21 total official and unofficial crossings over a stretch of 79 miles.  The overall average is one every 3.76 miles.  Some of them appear to have essentially no traffic, but may be there just to maintain effective, if unused, access.  Some link to apparently busier areas and probably see several vehicles per day.

[wxfree]

Google seems to think I didn't choose the correct zoom level, so it's showing all of them zoomed out further than I'd intended.  I didn't mean for them to be difficult to see at first glance.

[Alex]

I photographed every intersection regulatory sign I passed along I-10 eastbound while driving through West Texas in January 2006. I can go through those and tally them up when I get back to my home PC.

[wxfree]

Thanks, that would be interesting to know.

I counted along I-40, and it seems to have a crossing about every 50 feet.  All of these are officially signed and have provision for left turns.

https://www.google.com/maps/@35.185083,-102.989981,394m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@35.1914459,-102.9681578,394m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@35.194593,-102.960102,394m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@35.2057719,-102.9312747,394m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@35.21154,-102.917994,394m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@35.2183168,-102.8993126,394m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@35.227831,-102.862612,394m/data=!3m1!1e3?hl=en

https://www.google.com/maps/@35.235451,-102.841412,394m/data=!3m1!1e3?hl=en

There are 8 over a distance of 9 miles, so nearly one per mile on average.

[3467]

There is something close in Illinois. There is a gate and access point for emergency vehicles on I-74 near the rest area between Galesburg and Peoria. On the 1-88 Tollway there were a couple of these with warning signs "Watch for Trucks entering and leaving highway"

[aboges26]

Naturally there is Interstate 180 in Cheyenne that is all at grade.

Also, Interstate 75 at the Mackinaw Bridge in Michigan has RIRO movements on both sides.

[The Ghostbuster]

Could these at-grade encounters be eliminated? Or is it the only way to provide the needed access?

[wxfree]

Could these at-grade encounters be eliminated? Or is it the only way to provide the needed access?

Part of my intention taking this inventory is to have the information needed to figure out the most efficient system of frontage roads and overpasses to eliminate the at-grades.  They need to be mapped out and categorized as north, south , or both side intersections, and then we can look at different ways of controlling the access better.

But that part of the discussion probably belongs in the Fictional forum.

[thenetwork]

I remember there used to be no less than 6 at-grade crossings on I-280 in Toledo (Wood County section) until they brought the freeway up to interstate standards in the early 80s:

South to North:

- Hanley Road
- Latcha Road
- Ayres Road
- Lemoyne Road
- Walbridge Road*  This was the only signalized intersection at the time.
- Curtice Road

The Wood County post of the Ohio Highway Patrol (between the Ayers & Lemoyne Road intersections) back then may have had it's own access driveway even though it was on Lemoyne -- that I cannot recall.

[Alex]

I photographed every intersection regulatory sign I passed along I-10 eastbound while driving through West Texas in January 2006. I can go through those and tally them up when I get back to my home PC.

Looking back at my photos, I photographed 14 at-grade intersections along Interstate 10 east between Exit 55 / Hudspeth County line and Exit 138 / Van Horn.

[Avalanchez71]

I only recall seeing like two on I-40 in Texas.  Is there on in NM on I-40?  I exited and followed one of the old US 66 segments.

[aboges26]

I only recall seeing like two on I-40 in Texas.  Is there on in NM on I-40?  I exited and followed one of the old US 66 segments.

No, there are no at-grades on I-40 in NM.

[J N Winkler]

No, there are no at-grades on I-40 in NM.

Actually, there is at least one, near the Rio Puerco bridge west of Albuquerque (post in another thread with StreetView links).  It is marked as "temporary" but I think that is a fiction born out of legal necessity.

[aboges26]

No, there are no at-grades on I-40 in NM.

Actually, there is at least one, near the Rio Puerco bridge west of Albuquerque (post in another thread with StreetView links).  It is marked as "temporary" but I think that is a fiction born out of legal necessity.

YES!  I had forgotten about that one, and had actually thought that it would be temporary.  Why can they not cut the access?

[J N Winkler]

The problem for a highway agency is that withdrawal of access counts as a taking against land, which has to be paid for.  If you withdraw the only access to a property, you may as well purchase it outright since it has no value if an owner cannot reach it directly from the public road system.

In the case of the "temporary" driveway on I-40, a Bernalillo County plat map would probably give us our best clue to the actual answer, but I suspect that driveway is the only access to an isolated and fairly large parcel of rangeland, and stopping it up would mean either acquiring the land outright or building a road to it--both options being quite expensive compared to allowing the "temporary" driveway to persist indefinitely.

[Revive 755]

There are a few at grade/RIRO accesses on I-40 in North Carolina between the Tennessee Border and Asheville

1) Aerial Streetview

Should have been an interchange since it is already a connector road to an underpass

2) AerialStreetview

3) Aerial Streetview EB Streetview WB Looks like this one shoudl have been an interchange as well.

Colorado managed to keep I-70 as a freeway through Glenwood Canyon with regular on/off ramps where the terrain is just as bad, if not worse.  I don't see why North Carolina got an exception.

[J N Winkler]

Colorado managed to keep I-70 as a freeway through Glenwood Canyon with regular on/off ramps where the terrain is just as bad, if not worse.  I don't see why North Carolina got an exception.

These all appear to be in Great Smoky Mountains National Park, so I suspect that may be a factor.

[SteveG1988]

Colorado managed to keep I-70 as a freeway through Glenwood Canyon with regular on/off ramps where the terrain is just as bad, if not worse.  I don't see why North Carolina got an exception.

These all appear to be in Great Smoky Mountains National Park, so I suspect that may be a factor.

Different eras of construction. By the 1980s and 1990s we were able to do it safely.

[roadman65]

I saw one on I-44 someplace between Tulsa and Vinita, OK.  It was a dirt road and led onto a ranch of some sort from the EB lanes.

[rte66man]

I saw one on I-44 someplace between Tulsa and Vinita, OK.  It was a dirt road and led onto a ranch of some sort from the EB lanes.

I believe what you saw is one of the many non-public access points for maintenance crews to access the pike.  With a Jersey Barrier nearly it's entire length, it is difficult to access otherwise.  All of the OK turnpikes have them.

[lepidopteran]

There used to be several at-grade intersections on the western I-76.  In the mid-80s, it looked like the EB lanes were once a 2-lane road as evidenced by the undulating hills, while the WB lanes were nice and flat (someone else mentioned an even stronger difference in their bridges.  I think these were all cleared up by the early '90s.

Regarding I-280 in Toledo, a mid-60s Rand McNally road atlas (which I'd like to get rid of, BTW), actually showed the Interstate shield on a road with the non-freeway color at that point.  It was honest about the highway's status, you might say.