What states mark the names of roads on freeway overpasses, and which ones don't?

[michravera]

I wish California did.  I think it help in navigating while driving.

In general, CalTrans does. They just don't always mark them so that the public can see them. AZDoT seems to do it very consistently on the overpass over approximately the middle of the road. I'm not sure, but AZDoT may not mark the overpasses that have the same names as the exits that are signed, but they seem to get all (or almost all) of the others on I-10. It's sort of like signing an intersection, even though you can't turn onto the cross street.

[jakeroot]

Alabama didn't until about 15 years ago, then they instituted a program to add such signs to Interstate overpasses, even those that had interchanges.

Washington, for the longest time, also did not discern between interchange and non interchange road (new example, older example).



In doing more research, newer examples are not as rare in WA as I previously thought. Still, they've become rarer.

[kphoger]

Mexico has a habit of naming bridges.  Practically every little stream the highway crosses over comes with a road sign telling you what it is.  Some of the names are just that of the body of water, while others have unique names.  But some get rather inane, such as this bridge over an old alignment, whose name translates to "Highway Underpass Bridge".

You can even find named pedestrian overpasses, such as this one nearby, whose name translates to "El Mesón Pedestrian Way".

[Bitmapped]

The Ohio Turnpike marks bridges. As others have noted, Ohio DOT itself generally does not.

West Virginia consistently posts bridge clearances, but not road names on bridges.

[machias]

New York is pretty consistent with a small sign on the bridge itself, example here, but I prefer the more visible PA-style standalone signs, like this one.
Notably, however, New York doesn't typically sign underpasses, only overpasses.

NYSDOT is consistent within regions, but can vary from region to region. For example, R3 tends to mount the sign on the overpass, R4 tends to mount it next to the overpass. R2 doesn't do it at all.

[vdeane]

New York is pretty consistent with a small sign on the bridge itself, example here, but I prefer the more visible PA-style standalone signs, like this one.
Notably, however, New York doesn't typically sign underpasses, only overpasses.

NYSDOT is consistent within regions, but can vary from region to region. For example, R3 tends to mount the sign on the overpass, R4 tends to mount it next to the overpass. R2 doesn't do it at all.

Yep, and underpasses can vary by where you are as well.

[US 89]

South Carolina uses a letter S followed by two sets of numbers. I believed these are the unnamed roads that have numbers while numbered routes like US 15 would have it marked as such.

[https://live.staticflickr.com/65535/50399008396_b5d772a664_4k_d.jpg[/i]

I believe that is just the designation for a South Carolina secondary highway. The first set of numbers refers to the county, the second to the individual route. The 27 on the picture above means that's in Jasper County.

[sprjus4]

Virginia does on interstate highways, somewhat varies on arterial freeway segments.

Some examples:
https://www.google.com/maps/@37.5092031,-77.125658,3a,42.3y,279.69h,87.11t/data=!3m6!1e1!3m4!1sWKLp72hh34ez_SalzKlqxQ!2e0!7i16384!8i8192
https://www.google.com/maps/@37.8817551,-79.548506,3a,75y,117.69h,89.99t/data=!3m6!1e1!3m4!1sCSI1xxzmPqMYRCs739lk-g!2e0!7i13312!8i6656
https://www.google.com/maps/@37.2810616,-78.4261653,3a,45.6y,318.47h,89.58t/data=!3m6!1e1!3m4!1sMmV6EdNIOh8dnE5LMaMnzA!2e0!7i16384!8i8192
https://www.google.com/maps/@39.0611312,-78.2355137,3a,38.3y,33.55h,87.85t/data=!3m6!1e1!3m4!1s2SddfSRcxbBo-8ReXeKhTg!2e0!7i16384!8i8192
https://www.google.com/maps/@36.631911,-76.2156663,3a,41y,345.46h,87.54t/data=!3m6!1e1!3m4!1sfVxRXb3AV5EHpjgmYaWxHQ!2e0!7i13312!8i6656

[wriddle082]

About 20 years ago, Tennessee started marking them in urban areas only with blue signs.  I think it coincided with the initial installation of 2/10 mile reference markers.  Wish they would do it all over the state, especially since they seem to now be posting the reference markers in rural areas now.

[J3ebrules]

New Jersey! They do indeed mark the overpasses of roads. Even sometimes roads that don't exist! (Referring to Tri-Borough road on NJ 24; still marked as a testament to the failure).

[hbelkins]

Kentucky is hit-and-miss. When I was growing up, route numbers were marked, but local roads were not. The practice was discontinued for many years, even though the marking of them was noted in the state's signage policy. Over the last 20 years, the practice has resumed, although not all districts mark unnumbered local roads that are known only by name. There are a few instances of this on I-75 in District 6.

West Virginia does not.

[Mapmikey]

Virginia does generally with road name and route number (usually secondary).  There are a fair number that are route number only (it could be a VDOT district thing)

North Carolina does route number only in the modern era.  Originally they did road name only for non-primary routes.

[I-55]

Alabama didn't until about 15 years ago, then they instituted a program to add such signs to Interstate overpasses, even those that had interchanges.

These signs also include the mile marker at the bridge.

[mrcmc888]

Georgia's overpass markings are consistent, Tennessee's and Virginia's less so.

[US 89]

Alabama didn't until about 15 years ago, then they instituted a program to add such signs to Interstate overpasses, even those that had interchanges.

They have them on more than just interstates though. I know for sure the US 80 freeway in Phenix City has them.

[STLmapboy]

Texas does not typically (save Fort Worth, which also puts the block number). They are, however, extremely consistent about clearance signs, and signs warning of those clearance signs.

[roadman65]

The NJ Turnpike would use the milepost to identify overpasses as that particular freeway does not even sign counties or municipalities along it.  Heck, I do not think river names are used, but I could be wrong on that one.

Kansas is another one that uses mileposts on overpasses for identification purposes on the KTA.  Some use three digits to the right of the decimal to make it seem like a larger number than really is, but  just look to the left of the decimal and you will soon figure it out.  Though KTA still does in some cases use names in addition to the milepost number.  Even on the former Emporia overpass for Exit 127, it used to read "EMPORIA INTERCHANGE" to identify the road name being it is more of the ramp system even though I-35 S Bound did use that bridge to loop around onto the toll road.

[Scott5114]

Kansas is another one that uses mileposts on overpasses for identification purposes on the KTA.  Some use three digits to the right of the decimal to make it seem like a larger number than really is, but  just look to the left of the decimal and you will soon figure it out.

These are technically not mileposts but bridge numbers that are milepost-based. There are a few instances where rather than using an actual milepost, a bridge gets the same bridge number as a nearby, related bridge with an "A" suffix.

[roadfro]

Nevada marks the names of overpasses along freeways, but seems to be more of an outlier in its implementation.

The original implementation of this was along the US 95 freeway in northwest Las Vegas in the late 1990s-early 2000s, from approximately Washington Avenue to Lone Mountain Road. A small street name sign was affixed to the overpass. To my knowledge, this is the only stretch of freeway in Nevada to ever do it this way.

Beginning in the 2000s, NDOT (and Clark County, in the case of CC-215) incorporates the street name as part of the aesthetic treatment on the bridge, either engraved or as a separately-affixed decoration element. Since different projects have different aesthetics, all these overpass markings look different–in many cases, the example here is representative of similar treatments along a stretch of freeway where a major corridor enhancement was constructed or where NDOT/Clark County has adopted a corridor design scheme. While this practice started in the Las Vegas area, it spread to northern Nevada in the 2010s.

Comparison:

• US 95: Smoke Ranch Road overpass (original, 2009 view, but in place by late 1990s)
  
• US 95: Smoke Ranch Road overpass (current, 2019 view, but in place by 2016)
  

Other examples (with approximate bridge construction or aesthetic install dates):

• US 95: Valley View Blvd interchange (central Las Vegas, circa 2004)
  
• US 95: Azure Dr/Tropical Pkwy overpass (NW Las Vegas, circa early 2000s) (rotate slightly left to see Tropical Pkwy on far side)
  
• I-515/US 95: Auto Show Dr interchange (Henderson, 2005)
  
• I-15: Sunset Road overpass (southern Las Vegas, circa 2012)
  
• I-15: Cactus Ave interchange (far south Las Vegas, circa 2013)
  
• I-15: St Rose Pkwy (SR 146) / Southern Highlands Pkwy interchange (far south Las Vegas, circa 2009)
  
• CC-215: Rainbow Blvd interchange (SW Las Vegas, 2004)
  
• CC-215: Charleston Blvd (SR 159) interchange (western Las Vegas, 2000)
  
• CC-215: N. 5th St interchange (North Las Vegas, 2011)
  
• US 95: I-11 interchange (Boulder City outskirts, 2018)
  
• I-80: Evans Ave overpass (downtown Reno, circa 2012)
  
• I-580/US 395/US 50: Snyder Ave overpass (Carson City, 2017) (also inscribed is the translation of "Snyder Ave" in the language of the indigenous tribes in the area)
  

However, it is not a practice in Nevada for the name of the cross street for freeway underpasses to be marked in any way. I've never seen it done.

[Hot Rod Hootenanny]

Ohio used to  - but they seem to have mostly discontinued that practice in the last 15-20 years.

I'll give a third different answer concerning Ohio. When the interstates were first completed, they had signs on all the bridges. Over time, those signs disappeared, be it from the signs falling apart, or ODOT deciding not to replace them after repainting the bridges. Since 2000, ODOT has occasionally signed roads (I-71 in Ashland Co, I-75 in Hancock Co, I-271 in Cuyahoga Co), but its too inconsistent to get a pattern. (sort of like exit numbers for non-interstate freeways) 

[MCRoads]

Oklahoma does not post street names on bridges , but very consistently posts hight signs, even for almost unreachable heights (they seem to not mark them over 20'), and rediculus angles.

Found some exceptions to the 20 ft rule:

https://goo.gl/maps/x1HuzCW3jzjZu1Fr6
https://goo.gl/maps/b7neEx66VhzLN6958 (Weird angle as well!)
https://goo.gl/maps/DaQ7EfZqANK7sy5c8 (ditto)

[CoreySamson]

Pretty sure Texas, Arkansas, Mississippi, Louisiana and Tennessee don't do it very often if at all.

Although Alabama does, and I love the way they do it.

[hobsini2]

In my experience...
Wisconsin...
All state highway and county highway bridges are signed. The locally named streets are signed about 3/4 of the time especially in Milwaukee, Oshkosh/Appleton/Fox Cities/Green Bay and Madison.
Illinois...
All tollway overpasses are signed. North of I-80 and East of Route 59, all other interstate bridges are signed. Downstate, about 1/4 are signed.
Indiana...
90% of all bridges are signed. The new bridges over I-69 between Bloomington and Evansville are not labelled too many times. But they all have these little blue markers like this...https://www.google.com/maps/@39.3039224,-86.5167513,3a,15y,25.54h,85.84t/data=!3m6!1e1!3m4!1sV77guxYD-bJmodHLFKpAmg!2e0!7i16384!8i8192?hl=en
They correspond with the mileage markers.
Tennessee...
In Nashville, they are signed well. Outside of Davidson County, not much.

[Takumi]

Virginia does generally with road name and route number (usually secondary).  There are a fair number that are route number only (it could be a VDOT district thing)

There are one or two on I-64 west of VA 288 that have the road name greened out, with just the route number visible now.

[plain]

Another VA example is RMTA's Downtown Expressway (VA 195), though many have been taken off the overpasses themselves and mounted on the ground instead.