Hi Richard,
This has already been discussed here.
Have a look to those threads please :
https://lists.openstreetmap.org/pipermail/tagging/2017-December/034291.html
https://lists.openstreetmap.org/pipermail/tagging/2018-January/034932.html
https://lists.openstreetmap.org/pipermail/tagging/2018-Feb
Hi,
> https://wiki.openstreetmap.org/wiki/Proposed_features/Hydropower_water_supplies
I think that the proposed invention of waterway=pressurized and its use
for water in pipelines as well as natural caves should get some
discussion in the mailing list.
What do people think?
Richard
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