[OSM-talk-be] Conventions of primary/secondary/tertiary

[Ben Laenen]

Kenny Moens wrote:
> Hello guys,
>
> On the wiki page the conventions for "primary/secondary/tertiary" roads
> are marked with question marks. Is there already a formal definition for
> those? Until now I've always applied these rules and they apply pretty
> good, however... some road I have problems with is the N286 connecting
> Tildonk - Wespelaar - Wakkerzeel - Werchter, the road is still marked as
> such in the field, both on traffic signs and on the kilometer poles, but
> the road is (certainly the section Wespelaar - Werchter) barely 4-5m
> wide... I don't think its a good idea to tag such a road as secondary
> then...
>
> Any suggestions?

The N286 is no longer a secondary road. The Flemish Region has given the road 
to the municipalities (Haacht, Herent and Rotselaar), so it's no longer the 
N286. A little bit of googling will direct you towards the texts of the 
Staatsblad.

But of course it takes a while before the road numbers are all gone on the 
ground. Chances are there will still be some signs of the N286 in ten years if 
you look at other cases of demoted N-roads. In order to give future mappers a 
hint that the road is no longer secondary, I add the tag "old_ref=N286" in 
these situations, because some other mappers will likely make it secondary 
again and add the ref numbers again. But experience tells me that they usually 
don't see the old_ref tag and will make them secondary again nevertheless...

So basically, just handle the road like you would if it didn't had a road 
number. It's not exactly a road with trough traffic anymore in some places, so 
it can well become unclassified there.



That said, the question marks on the wiki page were there because the rules 
were never really written down well -- something I'd like to do if I have some 
time. Which isn't immediately obvious as it's written down is that you could 
well bend those rules a little bit to match the topology. If a road has a road 
number but it lost all functions of handling through traffic, there's no point 
in keeping it secondary. This bit of N105 for example: 
http://osm.org/go/0EpLTtUuA- between the R6 and Kasteellaan, is just a small 
residential street with a dead end.

Likewise you could give secondary or primary status to roads that don't have 
road numbers (for example when a primary road has for some reason a dead end 
on an unnumbered road which connects it to another primary road a few hundreds 
of meters further). An example: http://osm.org/go/0EpI5Dea here the 
Bedrijvenlaan between N109 (also Bedrijvenlaan), and the roundabout on the 
B101 isn't part of the N109. Yet it is used by all traffic to get there from 
E19, so you can make it secondary on that little bit.

And there is more bending of those rules possible with city centers, roads 
with suffixes and other special cases where you basically have to decide based 
on the topology of the road network what to do with them.

Greetings
Ben