| +/- waterway=river
For narrow rivers which will be rendered as a line.
How to map
To map a river make a simple way. Add the waterway=river tag to it. The direction of the way should be downstream (i.e., draw the way in the direction that the river flows).
You should also add a name with name= if it's known.
For wide rivers use Tag:waterway=riverbank to create separate ways for the two river banks. Note that a central way is still needed.
width=* to indicate the width in meters. This is an approximate average width of the river throughout most of length of that bit of river. You can use width=5 or width=5 m to tag a river with a width of 5 meters.
depth=* to indicate the depth of the river. This is the maximum depth of the river, averaged over the length of that bit of river.
A lot of rivers also have non-physical tags (e.g., access restrictions). These tags are almost the same as tags used on highway=*. Some tags include maxwidth=*, maxheight=*, maxlength=*. For access restrictions, see the access page.
Direction of flow
The OSM convention is that the way should be drawn in the direction the river flows. If you are drawing a way and you are unsure of the direction the water flows you could add a tag such as "fixme=direction unknown" to the way.
Just as with highways, it is important that the topology of rivers is correct. That means, if you can go from one part of the river to an other part of the river via the water, there has to be a piece of waterway=* between them.
This implies that a way tagged as waterway=river should not stop on the riverbank of another river, but should proceed to the central way of the other river.
- waterway=riverbank for large rivers where you would like to draw river's banks
- waterway=canal for artificial open waterway used for transportation, waterpower, or irrigation
- natural=water for water surface such as lake
- Relation:waterway for drawing long rivers in a relation where you would need several ways connected