[Talk-us] "highway" tags in the US

Karl Newman siliconfiend at gmail.com
Tue Mar 4 18:47:05 GMT 2008

On Tue, Mar 4, 2008 at 10:26 AM, Alex Mauer <hawke at hawkesnest.net> wrote:

> As far as I know from the history of OSM unclassified and residential
> are basically the same, and they render the same in pretty much every
> renderer.  I believe it's a historical artifact where "residential"
> pretty much meant "unclassified+abutters=residential".

Hmm... Then why are all the generic roads from TIGER marked as residential?

> >     The first part of your description of unclassified seems to fit
> there,
> >     as well: "urban commercial district or rural low-density housing..."
> >
> >     I suppose we differ in that I feel that tertiary can scale: in a
> >     residential area, it's the "main roads with fewer driveways", in a
> >     commercial or industrial area, it's the main roads as well, and in
> rural
> >     areas it's main roads which are not county highways.
> >
> > I think it's not so good to make the tertiary tag cover all those cases.
> > As you've described it, in a residential neighborhood, that road is
> > generally 25 MPH, in a commercial or industrial area it's usually 35
> > MPH, and in a rural area, 40-55 MPH. I think only last one makes sense.
> Other roads change speed as they enter urban places (e.g. primary roads
> may go from 55 down to 25 to pass through a hamlet)  Why shouldn't
> tertiary be the same?  It's all about the relative status of a road to
> the roads around it.

But the residential road is slow for its entire length, whereas your hamlet
example is only slow while in the town.

> >     I would not use "direct driveway access" as a factor for
> distinguishing
> >     highways.  Roads of all classifications except motorway may have
> direct
> >     driveway access, especially in rural areas.
> >
> > It's just a guideline, and it goes toward expectations. Driving down a
> > residential street, I expect to have to watch carefully for kids playing
> > or for drivers backing out. I realize that almost any road can have
> > direct driveway access, but it's very infrequent (more like every 1/4
> > mile at least, not every 100 feet as in a residential neighborhood). On
> > a more heavily-traveled road with a higher speed limit, the driver
> > pulling out has to be more careful than the through traffic.
> Hmm...it seems to me that perhaps you're writing this from a perspective
> of "what a driver using the road might expect", while I'm coming from a
> perspective of "how should this road be tagged".  Is that the case?

"How should this road be tagged" needs to consider the expectations of a
driver/bicyclist/pedestrian. I've always been uncomfortable with the "if it
looks like a motorway, then tag it as such" for a couple reasons. First,
does it meet the standards for a motorway in terms of height restrictions,
turn radius, restricted access, etc. Second, over what distance are you
going to consider the road characteristics? Part of my commute route follows
a state highway that looks like a motorway in isolated sections--dual
carriageway, 60 MPH, restricted access, etc., but it has stoplights at grade
intersections every mile or so, sometimes more often. Also, if you continue
on the road, it peters out into a 2-lane highway with slow tourists and
grinds through pedestrian-clogged tourist-trap towns. Not a motorway.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-us/attachments/20080304/90f62b9b/attachment.html>

More information about the Talk-us mailing list