Should ref=* for Texas State Highways begin with "TX" or "SH"?

As a former proponent of using “TX” for state highways while MapQuest Open was still active, I’m strongly in favor of using “SH” now.

I’m not as convinced on “IH” for Interstates. While it is common to see blade signs with these letters in Texas, it hasn’t caught on in colloquial speech—we still just say “I” like the rest of the country. If a Houstonian needs to turn right on IH 10 Frontage Road, they’ll probably say “turn right on the I 10 Feeder” instead.

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Only certain parts of the country say the I-whatever. Here in this part of New England we tend to drop not only the, but also I, and the letter “R” in most words.

So it’s just… “jump on 95 north for a few exits, then hop on 117 and go down past where the Dunkin’ used to be.”


I thought preceding a highway name with ‘the’ was only a California thing, don’t tell me its spread to Texas?

Sounds like it’s time to retag some SoCal freeways as ref=The 405!

I think @1ec5 has some fancy ways in wikidata to determine a mechanism for “how local folks actually describe routes”…

That would be the road name formatter (P8498) property, which is already tagged on most Wikidata items that describe route networks, including Interstates. I don’t know of any software that uses it yet. Ideally, geocoders and turn-by-turn navigation software would use this data to supplement OSM’s way and relation tags, but I recognize that it requires nontrivial work at multiple levels for existing data consumers.

In my opinion, until we’re ready to take the momentous step of eliminating ref=* tags from ways, we might as well use them to communicate the route number in a format that locals would recognize. However, I don’t think we need to get into the weeds of encoding whether locals put a definite article in front of the route number. Many languages use keys such as name:genitive=* to communicate similar grammatical properties, so some kind of ref:article=* wouldn’t be out of the question – except this isn’t very relevant to Texas. “The” appears in @clay_c’s example because it modifies “I-10 feeder”, a description of a frontage road.

In Texas, replacing the “TX” prefix with “SH” would be an obvious improvement. The overwhelming usage of “SH” in official and colloquial speech and writing is partly because Texas has many state highway networks, making “Texas” or “TX” too ambiguous. Yes, State Highway shields say “TEXAS” on them and some even bear a wavy Texas flag, but Farm-to-Market and Ranch-to-Market shields are shaped like the state.

I provide this press release and this and this as evidence that in Rhode Island, all non-Interstate routes are described as “Route X” regardless of network (could a state highway, or a US highway). Interstates are either “I-95” or just “Route 95” in vernacular, but at least RIDOT does use the I- designator for interstates.

Based on this, and since we still cannot remove them wholesale, how would you recommend tagging the ref way tags in Rhode Island? Should I say ref=Route 1 for what the rest of the country would call “US 1”? ref=Route 117 for the state route of the same name?

I would start a new discussion about Rhode Island, as it’s quite off-topic for a thread about organized editing of express lanes in the Dallas area. (Edit: And it’s still off-topic for the thread about Texas refs that got split out.) Maybe you don’t even need to prefix the refs for state routes in Rhode Island! Every state has different practices in naming their routes, both officially and unofficially. The status quo of postal abbreviations in most states is the closest we ever came to national consistency, and I would contend that it was for naught, because route relations are awesome.

The U.S. Numbered Highway System presents a particular conundrum, but not just for refs. It turns out that half the states call them “U.S. Routes” while the other half (including Texas) call them “U.S. Highways”. It’s a good thing we’ve segmented the route relations by state so we don’t have to debate the one true naming convention among states that won’t see eye to eye.

I’d say loc_name=The 405 would be entirely appropriate! Local names - OpenStreetMap Wiki

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Here’s an illustration of the ambiguity when State Highway numbers are abbreviated as “TX” instead of “SH”. I realize it isn’t a huge deal if the user can familiarize themselves with seeing or hearing “TX” or “Texas” along these highways, especially if a data consumer synthesizes the route’s name from the route relation’s tags. But in my opinion, the “TX” prefix was an almost arbitrary choice, and nothing should be relying on it anymore.

A sign assembly consisting of a State Highway 121 shield, with the name “TEXAS” below the number 121, as well as two Farm to Market Road shields in the shape of Texas.

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There was some more discussion in #local-texas on the OSM-US Slack, which I’ll summarize here.

@csomerville questioned another user’s recent edits changing refs on highways from “SH” to “TX”. I explained that “TX” became the de facto standard back when the MapQuest Open renderer was active, as it parsed the state abbreviations in ref values to determine which shield icon to display.

@txemt stated that the distinction is that “SH” is for toll roads and “TX” is for others. I was skeptical of this, as I can’t recall ever seeing “TX” on the ground in my experience traveling around the metropolitan Texas Triangle, but I do remember seeing several instances of “SH” on non-tolled roads. I began to compile a list of such cases:

Additionally, I mentioned that TXDOT's Highway Designation Files refer to state highways internally as “SH”.

@txemt provided an example of “HWY” in the Permian Basin:

Perhaps there are examples of “TX” out there on signage, and this variance may be a consequence of different TXDOT districts or local governments. But from my experience, “SH” appears to be more prevalent on the ground, and I would expect the average Texan driver to be familiar with it.

Here’s some background as to why “TX” is so commonplace in OSM:

Ignoring the states that held out against the convention of state postal abbreviations, Texas was one of the last states to get moved over to that convention. In 2014, it was still pretty easy to find “SH” on Texas roadways.

That would be incorrect. TxDOT has standardized on “SH” as the only acceptable abbreviation for “State Highway” on signs. I’m unaware of any source in the media or the software industry that reserves “SH” for toll roads only. The main parties that consistently use “TX” are OSM, TomTom (in navigation guidance data), and roadgeek websites.

Internally, TxDOT uses an elaborate system of two-letter abbreviations for various highway designations. Some of them are quite obscure, like “SL” for State Highway Loops. I don’t think we need to conform to what TxDOT uses internally, but “SH” (and to a much lesser extent “IH”) have been adopted by the public because of signage and frequent mentions in the media. Waze has similarly standardized on the “common speech” approach to tagging numbered routes. We’re almost there, except for this “TX” prefix.

These street name signs’ red color is a telltale indication that a county or local agency put them up. Small towns across the country often generically refer to “Highway” because they only have to worry about a single highway within their jurisdiction. Noncompliant red street name signs also seem to be a favorite of rural small towns in some states (Indiana being another).

Texas regulations allow 13 different designs for street name signs, none of which are red. The department doesn’t always follow the TMUTCD to a tee, but they normally wouldn’t go out of their way to violate it by procuring a custom rectangular red sign blank.


FYI I made a table to collect the results of all this discussion on ref tags:
Feel free to update/edit as necessary.
User:SD Mapman/United States/State-Specific State Highway “ref” Tags - OpenStreetMap Wiki