OpenStreetMap
I read some of the wiki pages for Abandoned/Disused/Life_Cycle tags but it seems there's no answer to how to use these tags. I've been mapping an area around an old canal and could really use some way to distinguish the areas that still have water in them and the areas that have been filled in.
The former is still useful as a landmark and important to know about for navigation purposes unless you're carrying a canoe with you... The latter is only useful for people to understand the landscape (and why there's a footpath there) and for historical purposes.
It seems to me that's the basic distinction. Is the presence of the object important for navigation or useful as a landmark even if not for its original purpose? Or is it just being marked for informational purposes.
Discussion
Comment from Graham C on 2 June 2009 at 16:41
Whilst I can see value in OSM mapping historical features, it's really not designed for it at the moment. I'd suggest that the sections that are entirely unrecognisable as a canal on the ground (totally filled in) shouldn't be tagged as canal at all. If there's still a footpath alongside, maybe that should be somehow tagged as a former towpath?
Having read the proposal for an abandoned tag, it sounds like the difference between that and disused would be quite subtle. If you're talking about the Wilts and Berks canal, there's a group of people aiming to eventually restore it to a usable condition, so it's not entirely abandoned. Neither is it "merely" disused, as I think you'd have a job getting any kind of boat through most of it.
Given that abandoned is just a proposal, I'd be tempted to just tag everywhere that still looks a bit like a canal as disused, and delete the parts that have been filled in or replaced by roads/houses.
Comment from smsm1 on 4 June 2009 at 22:41
Proposals like the life cycle tag are rubbish because they can completely change the meaning of current tags. For example you should use amenity=old_pub if a pub closes. Similarly for a canal you would use waterway=disused_canal, which is similar to the tags that you use for railways.
Comment from marscot on 8 June 2009 at 21:58
I have mapped the monkland canal in coatbridge thats filled in and in other parts with water still in.