[Talk-us] US highway classification

[Nathan Edgars II]

On 5/27/2011 10:04 AM, Nathan Mills wrote:
> On Fri, 27 May 2011 09:26:41 -0400, Nathan Edgars II wrote:
>
>> No, trunk is also used for a major intercity highway that's not a
>> freeway. Take a look at the UK and their network of trunks.
>
> I'm sorry, I thought I posted to talk-us. My mistake. ;)
>
> Seems to me that trunk has no meaning if it is used in that way. In the
> UK, roads are classified based on the national government's
> classification of the roads (hence the confusing-to-us 'unclassified'
> tag. Since we don't have a single overarching national road network like
> that, I don't think that's a relevant model to use here.
How would you apply this argument to the use of primary to tertiary in 
the US?

 > Generally
> speaking, I think any divided and controlled access highway probably
> ought to be tagged as a motorway barring specific local circumstances
> that cause it to deserve a demotion and any divided, but merely limited
> access and not fully controlled access, highway probably ought to be
> tagged as trunk barring specific local circumstances.
>
> The 'major intercity' road ought to be tagged as primary unless there's
> a specific reason to upgrade, IMO. That leaves the data more useful to
> end users.

Actually that leaves it less useful for users in cities, as then there 
are only two classifications for non-intercity highways, secondary and 
tertiary.
>
> Also, I don't know how major a road between Dumas, TX and Texline, TX
> really is. If it weren't a US highway, I'd probably demote it all the
> way to secondary.

It's on the National Highway System, meaning the FHWA considers it to be 
a major road. It's probably the best route between Kansas City and 
Albuquerque.

Also note the proposed translation on 
http://wiki.openstreetmap.org/wiki/Highway_Functional_Classification_System 
, used by at least one mapper in Kansas. Principal arterials range from 
expressways to major two-lane intercity highways.