On Thu, 16 Aug 2018 at 18:20, Christoph Hormann <o...@imagico.de> wrote: > > On Thursday 16 August 2018, Martin Koppenhoefer wrote: > > > > The canal definition was changed in March 2018, before it said to use > > canal only for „the largest waterways created for irrigation > > purposes“ > > Yes, that was the obvious attempt to expand the narrow scheme to other > parts of the world in a superficial way oriented at the standard style > rendering but not at the actual semantics.
Actually, it's only drain that doesn't seem to make sense semantically, but ditch seems to be fine for smaller canals used for drainage and irrigation, at least according to the definitions by Wikipedia[^1] and the Cambridge Dictionary[^2]. [^1]: <https://en.wikipedia.org/wiki/Ditch> [^2]: <https://dictionary.cambridge.org/dictionary/english/ditch> I'm not sure if a (smaller) mill race can also be called a ditch, but i think it makes sense to have at least two tags for man-made channels of different width. In my opinion the material of the lining/confine should better be tagged separately, perhaps confine:material=concrete/wood/.... As for natural waterways, I could imagine the following classification based on width: * waterway=stream/brook - possible to jump across (< 1 m wide?) * waterway=creek - small to medium-sized natural stream (1-3 m wide) * waterway=river (3-10 m wide) * waterway=broad_river (> 10 m wide) Of course we could just use width=*, but it's not always easily possible to measure the width (e.g. in a forest) and sometimes it changes often. However, if new waterway=* values were introduced, it would be necessary that OSM Carto would render them from the day they were approved, otherwise people would not use them. Cheers Markus _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging