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Public-images-osm logo.svg stream
Tag used for further classifying streams in NHD imports Edit or translate this description.
Used on these elements
should not be used on nodesmay be used on waysmay be used on areasmay be used on relations
Useful combination


Status: imported

The stream tag is used fairly commonly to further classify a stream which has already been tagged with waterway=stream. The most commonly used values as of the time of writing describe continuity of flow throughout the year:

Value Meaning
stream=intermittent The stream only flows for part of the year, for a few weeks or months[1]. See also intermittent=yes, which has the same meaning, or seasonal=*
ephemeral The stream flows only during and briefly after precipitation, i.e. for a few hours or days. There's no precise demarcation between an epemeral stream and surface run-off.
perennial Water flows all year round [2].
permanent Presumably the same meaning as "perennial".
dry A dry river bed. Better to tag as ephemeral or intermittent if known (see below too)
* See TagInfo for a list of other values in use. These tend to be used more for the type of stream, although the values tend to be broken up by variety in synonyms.

The table above documents current usage only. You can help by expanding it to cover newly-emergent typing of streams.

Overlap with other tags

When distinguishing between perennial, intermittent and ephemeral streams, it may be better to use intermittent=* and not stream=intermittent:

  • There exist waterways which are too wide to jump and which are therefore tagged as waterway=rivers, but which are still dry for part of the year.
  • Without tags to the contrary, natural waterways should be considered perennial.
  • Ephemeral streams may suffer from a lack of easy verifiability; decide carefully whether such minor, indistinct rivulets are worth mapping and whether other mappers would arrive at the same decision.

Tag source

This tag is usage is solely coming from imports (specially nhd imports), not a real mapping[1]. Also, its usage is decreasing over time.

See also

  • waterway=* - general starting point for anything relating to flowing water
  • intermittent=* - a standard, more popular and widely used way of writing some of the uses of this tag
  • waterway=ditch - man-made drainage features which may or may not be flowing