[Talk-us] Update on potential highway classification reform

[Zeke Farwell]

On Tue, May 18, 2021 at 8:56 PM brad <bradhaack at fastmail.com> wrote:

> I think the fundamental problem is that we have too many tags for a
> functional classification scheme.
>

I don't find this to be the case.  Adam Franco and I have been discussing
highway classification for our state of Vermont and our current ideas are
something along these lines:

   - *Motorway:*  Interstate highways
   - *Trunk:*  The most important US and VT highways
   - *Primary:*  The rest of the US highways, medium importance VT
   highways, the most important town roads
   - *Secondary:*  Low importance VT highways, high importance town roads
   - *Tertiary: * Medium importance town roads
   - *Unclassified:* Low importance town through roads
   - *Residential:* The least important residential roads

There is some discussion over whether residential should be considered less
important than unclassified, or whether they are at the same level of
importance, but either way it does not feel like we have a problem of too
many tags.  The problem is that US highways are not universally more
important than state highways and the importance of each can vary greatly
depending on the route.

What I can say from studying UK road classification and how it maps to OSM
is that most of our US and state highways fill the space in the road
network intended for Trunk, Primary, and Secondary (some qualify for
Motorway).  So basically the only way to get a sensible small scale map in
the US is to do something like this:

   1. Consider the network of all US and State numbered routes *primary *to
   start
   2. Upgrade the most important routes to *trunk*
   3. Downgrade less important routes to *secondary*

It would be nice if the government did this work for us so we could just
look at the sign for a route and classify it accordingly (as they can in
the UK), but it's just not the case.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-us/attachments/20210518/299d953f/attachment.htm>