|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 riverbank 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'.
Areas intermittently covered by water
These areas can be flooded during high water level and are covered by plants when the water level is low. Tag such areas as natural=wetland + wetland=marsh;swamp;reedbed. Do not double tag or overlay with duplicate area of water=river or natural=water as the definition of wetland indicates occasional cover with river water.
Areas without vegetation
Some areas of river do not support growth of plants, but the surface of the riverbed can become exposed during low water levels. Some people tag these with surface=* e.g.surface=mud;gravel;rock in combination with natural=water + water=river + intermittent=yes. (Similar to tagging of natural=shoal or wetland=tidalflat)