Greetings.
Following the discussion in this topic, a proposal was created to “detach” man _made=windmill and man _made=watermill from the building scheme, thus creating a better scheme.
All comments and suggestions are welcome here, on the wiki page and tagging mail list.
Proposal:
https://wiki.openstreetmap.org/wiki/Proposal:Tagging_scheme_for_windmills_and_watermills
Regards.
Hi, A wind pump is not a mill. A mill mills, usually grain, and a pump pumps, usually water. They both harness wind energy. But a windpump is not also a windmill.
If you have a look into the earlier discussion linked above you would see that these wind driven waterpumps are commonly known as “windmill” in very large parts of the world, including the US and Australia. From that point of view it makes sense imo to tag them in OSM in the same way and add a subtag that these “windmills” drives waterpumps.
Do we know why we originally started distinguishing man_made=windpump from man_made=windmill? Was it only because they aren’t structurally buildings, or was it the semantic difference between milling and pumping, or was it because windpumps need a different tagging scheme or treatment by data consumers? I’d say that American English–speaking laypeople are unfamiliar with the distinction between windmills and windpumps, but it’s entirely possible that more technical language does make a distinction. After all, people often call wind turbines “windmills” too – anything tall with spinning blades, for that matter.
I am sure man_made=windpump had been introduced because it is a fact that these wind driven water pumps are not “mills”. I saw the first of those on the spanish Canary Islands and immediately thought of it as a pump, not a mill maybe because I have different picture of what a windmill is in my mind.
Nevertheless commonly people call them windmill - as you said, anything tall with spinning blades. And that is how most of them are tagged. You don’t need to look at the US or Oz, on the spanish islands (Canaries and Baleares) you will find hundreds of them tagged as man_made=windmill.
A wiki page saying these are windpumps does not make much difference. People will find “windmill” in the editors presets and - yep! - that’s it. That is why I encourage to accept the less precise term and tag them as windmill with the option to add “water_pump” (which is even more precise than windpump btw.).