|natural = water|
|Any body of water, from natural such as a lake or pond to artificial like moat or canal|
|Used on these elements|
|Tools for this tag|
Used to tag an area of water. The type of water body can be specified with water=*. Note that despite key name it is also used for artificial structures like moats, basins of a wastewater treatment plants, canals etc.
How to use
- Draw or select a closed way around the perimeter of the lake. It doesn't matter which way around the way goes.
- Tag the way with natural=water and maybe a name=*.
- For a lake, add a tag water=lake.
Creating islands in lakes
To create islands in a lake, the lake should be a Relation:multipolygon.
First create the lake:
- Draw or select the way around the perimeter of the lake.
- Create or select a Relation to serve as the lake.
- In Potlatch: the chain-like button just above the tag button accesses relations. It lets you create a new relation or add the way to an existing relation. Relations are listed as properties of the ways just like tags. Clicking on the left part of the relation accesses the relation's tags, and the right part accesses the tag's role in the relation.
- Tag the relation with type=multipolygon, natural=water, name=*, etc. Redundant tags should be removed from the way.
- Add the way to the relation and set the role to outer.
Then carve a hole in the lake by adding the island as an inner ring:
- Draw or select a way around the perimeter of the island.
- Tag the island as appropriate with natural=*, name=*, etc. If natural=* is missing, the island will assume the natural-type (e.g. wood) of the land surrounding the lake.
- Add the island to the lake relation with the role of inner.
Creating lakes on islands
Automatic water mapping
- JOSM plugin scanaerial works like OCR for water. You need 1 click per lake.
- natural=coastline is used for ocean coastlines
- waterway=riverbank - for the banks of large rivers, used in addition to the waterway=river way marking the centre line.
- water=* - a secondary tag for specifying what kind of area of water this is. e.g. water=lake, water=pond
Key:waterway may list some useful related features.