id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
17874	Propose to change landuse=reservoir to natural=water+water=reservoir	mkoniecz	team	"==== What steps will reproduce the problem?
1. Tag `landuse=reservoir` area
2. Select it
3. Run validator

==== What is the expected result?
Upgrade to `natural=water` + `water=reservoir` is proposed.

Note reservoir_type - https://taginfo.openstreetmap.org/keys/reservoir_type#values

For example reservoir_type=sewage that should not be changed to natural=water

==== What happens instead?
Nothing.

==== Please provide any additional information below. Attach a screenshot if possible.
Currently both `landuse=reservoir` and `natural=water` + `water=reservoir` are widely used for tagging reservoir water area.

`landuse=reservoir` is more confusing due to using `landuse` value and may be easily misunderstood to mean ""entire area used to maintain reservoir"" like most other landuses, and include for example also dam.

It is also more problematic for data consumers as to show water areas one needs in addition to `natural=water` query also for `landuse=reservoir` and other.

Encouraging `natural=water` + `water=reservoir` will not be problematic for non-broken data consumers as currently they anyway need to support it - it is a widely used tagging scheme, and dual tagging with `landuse=reservoir` is rare (below 3% https://taginfo.openstreetmap.org/tags/water=reservoir#combinations ).

`landuse=reservoir` is more popular but large part of difference is in node tagging and caused by imports - see https://user-images.githubusercontent.com/899988/60383077-c001ce00-9a6c-11e9-9aa8-ed43c7851a36.png

In recent years `natural=water` + `water=reservoir` seems to be more popular among mappers (though maybe it would change after excluding mappers that are not actually selecting tagging scheme that is used)

Note that there was a recent heated discussion about this upgrade rule in ID, see https://github.com/openstreetmap/iD/issues/6589

I participated in this discussion and based on my research (done to check whatever iD is making undesirable tag 'upgrades') I concluded that in this case tag migration is desirable.
{{{
URL:https://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2019-07-01 21:59:18 +0200 (Mon, 01 Jul 2019)
Build-Date:2019-07-02 01:30:51
Revision:15201
Relative:URL: ^/trunk

Identification: JOSM/1.5 (15201 en) Linux Ubuntu 16.04.6 LTS
Memory Usage: 461 MB / 869 MB (267 MB allocated, but free)
Java version: 1.8.0_201-b09, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: :0.0 1920x1080
Maximum Screen Size: 1920x1080
Dataset consistency test: No problems found

Plugins:
+ OpeningHoursEditor (34977)
+ PicLayer (35030)
+ buildings_tools (34982)
+ continuosDownload (82)
+ ejml (34908)
+ geotools (34908)
+ imagery_offset_db (34908)
+ jts (34908)
+ log4j (34908)
+ measurement (34977)
+ reverter (34999)
+ todo (30306)

Validator rules:
+ ${HOME}/Documents/install_moje/OSM software/josm/data/validator/deprecated.mapcss
+ ${HOME}/Documents/install_moje/OSM software/josm/data/validator/unnecessary.mapcss
+ ${HOME}/Documents/install_moje/OSM software/josm/data/validator/combinations.mapcss

Last errors/warnings:
- E: Failed to locate image 'presets/vehidle/restriction/toll_gantry.svg'
- W:  Toll gantry: Could not get presets icon presets/vehidle/restriction/toll_gantry.svg
- W: No configuration settings found.  Using hardcoded default values for all pools.
}}}
"	enhancement	new	normal		Core validator			template_report landuse reservoir natural water