|water = river|
|The water covered area of a river|
|Used on these elements|
|Tools for this tag|
How to Map
For long rivers the area should be split into several segments of manageable size (Area 1 and Area 2 in the image below).
In addition a way tagged as waterway=river, must be drawn in the direction of the river flow (way 4 in image). All tags of the river (like name=* and other supplemental tags) should go to this center line.
To map islands in a river you can use a multipolygon relation and the island and the main river bank should be included in the relation. The main riverbank way (way 1 in image) will have the role 'outer' and the way for the island (way 2 in image) will have the role 'inner'.