[Tagging] How to tag small canals?
selfishseahorse at gmail.com
Mon Aug 20 18:05:26 UTC 2018
I've written an issue request on openstreetmap-carto regarding the too
thick canal rendering:
On Thu, 16 Aug 2018 at 18:20, Christoph Hormann <osm at imagico.de> wrote:
> On Thursday 16 August 2018, Martin Koppenhoefer wrote:
> > >
> > > All of this together has its origin in the fact that in the UK and
> > > other early OSM countries large artificial waterways are almost
> > > always for navigation and small artificial waterways are almost
> > > always for transporting away undesirable water.
> > +1
> > That’s my analysis as well. What do you think, shouldn’t we fix the
> > wiki to make it more universally applicable to all kinds of
> > waterways?
> As usual i don't think you can change the definition of tags that are
> already used hundreds of thousands of times except by extending their
> scope which would make the tags more vague than they already are.
> What would make sense is to explicitly mention that waterway=canal does
> not have a lower size.
> Inventing a separate tagging scheme for irrigation systems might be an
> option too but irrigation is performed in very different ways in
> different parts of the world so it might not be too easy to create an
> universal tagging system for that.
> > 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.
> Going this route would essentially mean turning all of ditch/drain/canal
> into one big uniform catch-all. Removing the above is the attempt to
> salvage some of the semantic value in the data. Not sure how
> successful that is without support from the standard style though.
> Unfortunately waterway=canal has only 13k combinations with width=* and
> only 1.8k combinations with usage=* at the moment. Extending that
> would be the best way to move forward IMO.
> Christoph Hormann
> Tagging mailing list
> Tagging at openstreetmap.org
More information about the Tagging