If you want the full gory details, the latest discussions have been happening in #local-texas-beaumont, #local-texas, and #local-texas again.
I’m familiar with North Texas and Austin but have only been through Houston and Beaumont twice in my life, so take my observations with a grain of salt when applying them elsewhere in the state.
As a general matter, I don’t favor imposing artificial consistency in OSM where the real world intentionally lacks consistency. However, our thought process can be consistent. For example, the suggestion to “just map what’s on the sign” would be a consistent thought process, as would, “If in doubt, follow the local addressing system.” But a rigid formula loses information and requires us to pick a winner arbitrarily.
For the benefit of non-Texans reading this thread, here’s the 100 block of North Interstate Highway 35 Service Road – that is, the northbound frontage road along IH 35 north of the Colorado River in Travis County.
Just past the freeway underpass, here’s the 90 block of North Interstate Highway 35 Service Road – the southbound frontage road along IH 35 north of the Colorado River.
I would tag both of these parallel frontage roads with frontage_road=yes plus name=North Interstate Highway 35 Service Road, based on the identical signs and street addresses. They are two one-way carriageways of the same street that happen to have something bigger in the middle. As a result, the user will hear an instruction like, “Turn left onto North Interstate Highway 35 Service Road.”
But wouldn’t it be confusing if both carriageways are called “North” but only the first one leads to northbound IH 35? How would a motorist distinguish the two carriageways, other than left versus right? By tagging destination:ref=I 35 North or destination:ref=I 35 South based on the trailblazer signs:
Now the instruction will be something like, “Turn left onto North Interstate Highway 35 Service Road toward Interstate 35 South.” Wordy, sure, but a navigation system could choose to abridge the instruction based on context. For example, if the subsequent instruction is to bear left onto this southbound on-ramp, then the one before it could become simply, “Turn left onto the frontage road towards Interstate 35 South.” But if the user is headed for one of the hotels along the frontage road, then it could become, “Turn left onto North Interstate Highway 35 Service Road.” Valhalla already performs this kind of contextual guidance manipulation when choosing which of multiple destination=* values to call out, so it isn’t out of the question.
I included “Service Road” in the name because it’s verifiably part of the street name. A mapper can determine this by the street name signs or from the addresses of abutting properties. On the other hand, sometimes the “frontage road” or “service road” element is understood. For example, the signs along the North Stemmons Freeway frontage roads simply read “
Stemmons”.
I don’t think this means we should tag just name=Stemmons, because that takes the street name signs too literally. After all, the cross street has signs that say just “Empire Central”, but the name is indisputably Empire Central Drive. Here they just omitted the street types for readability:
At the same time, I wouldn’t invent a “Frontage Road” or “Service Road” suffix just to differentiate the street from the parallel freeway. If a navigation system needs to keep the user from thinking it wants the user to teleport to the freeway, it can replace the street name with “the frontage road” based on frontage_road=yes.
