[Tagging] Rivers classification

[Daniel Koć]

W dniu 07.08.2017 o 13:16, Richard pisze:

> the difference though is that in many countries every road has a roadsign
> identifying it as some kind of primary - secondary road type, also having
> legal implications someplaces.
> That doesn't seem common for rivers and I am wondering if this information
> will be ever useful to anyone.. probably not even your renderer as it would
> take years before a notable part of rivers are tagged.

The OSM types of road are not as objective and simple as you probably 
think. It's our internal classification which is not directly applicable 
to all the roads and needs some kind of agreement on the country level 
(hence "International equivalence" section on wiki). For example we're 
still discussing in Polish community about motorway/trunk difference. 
Waterways order is much more objective, because it can be simply 
computed (but there are some other problems - for example with data 
completeness and recalculations, as we already know).

As I said, this data may be useful for more detailed hydrological maps 
and analysis. I also don't have to show many rivers on a low zoom level 
- starting with the list of 20-50 biggest rivers would give good enough 
results and it can be done quite fast and accurate, since they are 
probably very well documented.

> Some rivers have waterway relations which could be used to make some
> classification?

What do you mean?

-- 
"Like a halo in reverse" [M. Gore]