[OSM-talk] highway=unsurfaced

[Cameron Patrick]

Ulf Lamping wrote:

> Now we have:
> highway=unclassified

"An ordinary road."

> highway=unsurfaced
> highway=track

<arrogant sod>
These ones are in use, but IMHO should die, replaced by surface=unpaved
instead.  Or at least explained better ... I've used highway=track for
roads navigable by 4WD but not ordinary vehicles, as well as abandoned
unsealed highways (e.g. Old Eyre Highway which was replaced in the 1970s
by a bitumen highway which runs parallel to it).  Since in many places -
Scandinavia and Australia, judging from mailing list responses - have
major routes which are unsealed, highway=unsurfaced is clearly the wrong
way to do things ;-)
</arrogant sod>

> trackgrade=gradeX

>From what I can gather, this makes sense in a very few circumstances but
is not so useful for general mapping of unsealed roads.  Does anyone
have data on how many roads have been tagged with trackgrade=?

> BTW: Please don't use very specific terms, none english persons like me 
> don't tend to know what "tarmac surface", "metalled surface" is. If you 
> are not able to describe a feature in a way that most people do 
> understand (including none english natives), please don't add stuff to 
> the map features page.

I'm (almost) not English and these make perfect sense to me :-p.  This
wikipedia article is a fine explanation:
        http://en.wikipedia.org/wiki/Tarmac

For reference, this is an ordinary sealed (bitumen / tarmac) road, which
I've tagged highway=trunk:
        http://cameron.ucc.asn.au/karratha07/photos/022-0818-1058b.jpg.html

And this one is highway=secondary surface=unpaved:
        http://cameron.ucc.asn.au/karratha07/photos/066-0819-1151f.jpg.html
(note that it's _not_ highway=unclassified - it's part of State Route 136
in Western Australia and runs for a few hundred kilometres:
http://en.wikipedia.org/wiki/List_of_road_routes_in_rural_and_remote_Western_Australia )

Sometimes after rain, bits of it look like this:
        http://cameron.ucc.asn.au/karratha07/photos/087-0819-1424.jpg.html
hence it is important to maintain the distinction between sealed and
unsealed roads on the map ...

If no one objects, I'll put something to this effect (or maybe a link
to this message) up on Map_Features.

Regards,

Cameron