[Talk-us] State highway refs (was Re: New I.D Feature)

Minh Nguyen minh at nguyen.cincinnati.oh.us
Sun Nov 30 22:58:53 UTC 2014

On 2014-11-30 10:41, stevea wrote:
> My two cents:  I must say that here in California, I've made it a habit
> to remove the "County Route" designation (CR) which precedes a ref
> number in our County Route system.  For example, NE2 (a banned-from-OSM
> former contributor for those unfamiliar with that history) entered ref
> tags for many G2, N1... county routes as "CR G2" and "CR N1."  That, in
> my opinion, is so redundant (as G and N and A and S... are well-known
> multi-county/regional-within-California county highway networks) as to
> be true clutter.  People in California do know (and routing software,
> renderers... SHOULD know) that A1, G2, N4 and S16 are county routes in a
> lettered system where each letter represents a cluster of counties...at
> least in California.

Some northwest Ohio counties post shields along section line roads that 
say A, B, C, etc. So far I've been tagging them like "CR A", even though 
you'd be hard-pressed to find that style anywhere outside of OSM. 
Instead of reducing ambiguity, I wonder if the "CR" may cause very mild 
confusion, for example when a router tells its user to turn onto "CR R".

> Also, while "SR" (for "State Route" in California and other states) is
> still legally correct, I still might change for consistency's sake any
> "SR" prefix I see in a highway route relation ref tag to be "CA"
> instead.  So, while "SR 17" is correct, I much prefer "CA 17" and will
> change it to that if I see SR in a California highway route relation ref
> tag.

Yes, usage is different in California. I've only ever seen "SR" on 
signage a few times, in rather obscure places. But in Ohio, it's ubiquitous.

> I agree with what we (as OSM volunteers entering/editing data in our
> map) now do, as well as what map styles/renderers and routing engines
> do, as Minh notes above:  "recognize the state abbreviation, SR or SH."
> Yes, Michigan still has its M- routes, and I think OSM (both its human
> editors and software components) should just learn to cope with that
> (plus perhaps a few other states) as exceptions to this largely (though
> not completely) applicable rule.  I believe we are pretty much there,
> but we still have edge cases, data in the map and newer contributors who
> are not completely familiar with these conventions in the USA.
> Discussing it here helps, though wiki documentation and taginfo data
> which are consistent across the fifty states is better.

My response to anyone who wants more consistency is that route relations 
are the way forward. They may be painful now but they make the data a 
lot less subject to interpretation.

minh at nguyen.cincinnati.oh.us

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