From OpenStreetMap Wiki
Jump to: navigation, search
Available languages — Relation:watershed
Afrikaans Alemannisch aragonés asturianu azərbaycanca Bahasa Indonesia Bahasa Melayu Bân-lâm-gú Basa Jawa Baso Minangkabau bosanski brezhoneg català čeština dansk Deutsch eesti English español Esperanto estremeñu euskara français Frysk Gaeilge Gàidhlig galego Hausa hrvatski Igbo interlingua Interlingue isiXhosa isiZulu íslenska italiano Kiswahili Kreyòl ayisyen kréyòl gwadloupéyen kurdî latviešu Lëtzebuergesch lietuvių magyar Malagasy Malti Nederlands Nedersaksies norsk norsk nynorsk occitan Oromoo oʻzbekcha/ўзбекча Plattdüütsch polski português română shqip slovenčina slovenščina Soomaaliga suomi svenska Tiếng Việt Türkçe Vahcuengh vèneto Wolof Yorùbá Zazaki српски / srpski беларуская български қазақша македонски монгол русский тоҷикӣ українська Ελληνικά Հայերեն ქართული नेपाली मराठी हिन्दी অসমীয়া বাংলা ਪੰਜਾਬੀ ગુજરાતી ଓଡ଼ିଆ தமிழ் తెలుగు ಕನ್ನಡ മലയാളം සිංහල ไทย မြန်မာဘာသာ ລາວ ភាសាខ្មែរ ⵜⴰⵎⴰⵣⵉⵖⵜ አማርኛ 한국어 日本語 中文(简体)‎ 吴语 粵語 中文(繁體)‎ ייִדיש עברית اردو العربية پښتو سنڌي فارسی ދިވެހިބަސް
Public-images-osm logo.svg watershed
Osm element relation.svg
Information about watershed relations

  • way - (blank)
  • way - main_stream
  • way - subbasin
Status: unspecified

This page collects all information about watershed relations.

There exists no proposal and no voting about this tagging.

Short description

(moved text from waterways page --Werner2101 14:49, 28 December 2012 (UTC))

A tag type=watershed got introduced to be able to describe a basin/watershed system of a river. Just adding child relations of tributaries to a parent relation does not get rendered/is not yet implemented/will never be implemented. For now one has to add all single waterway=river of a every single river to a parent river's watershed.

To also add areas (waterway=riverbank or natural=water) to the watershed-relation is not recommended - it would mean unnecessary overhead if there is already the waterway=river tag present in the relation.

History of watershed relations

  • 2009-06: user:katpatuka started creating watershed relations to simplify loading watersheds
  • ...

Current usages

Relation tags

Key Value Description
type watershed type tag of the relation
name name of the watershed / basin
parent_basin name of the parent_basin

Relation members

The following members are used in the current osm database:

Object type Role Recurrence Description
relation None * tributary relation with relation type=watershed
relation None * tributary waterways with relation type=waterway
way None * any kind of waterway ways. They usually have a waterway=[river, canal, stream, drain, ditch] tag
no riverbank areas or ways

see also: Taginfo about type=watershed

Do we need relations for watersheds?

Discussions on mailing lists, ...

Opinion of user:werner2101

Actually, I think that we don't need watershed relations. They can be created by scanning all upstream waterways starting with a relation:waterway. It is much easier to maintain single waterway relations and let a computer to the rest.

As long as the watershed relations exist, I think we should reuse as much upstream relations as possible and not add simple waterway way segments to the watershed relations.

I think it's a bad idea to mix waterway relations and watershed relations. This mixed mapping method is partly used in france, where tributaries of waterway relations are added to waterway relations with the role tributary.

This causes problems in wikipedia, too as the WIWOSM system can not distinct between normal members and tributaries. While the Rhein is displayed nice in wikipedia/WIWOSM, the Seine looks pretty bad with all the tributaries.

--Werner2101 14:49, 28 December 2012 (UTC)

Yes, we need

We need some way to get together all members of a water basin, since it's one of the most important geographical features. This means also getting together the borders, i.e., the ridges, actually what is called a watershed, since actually it constitutes the shed, that is a sort of surface shape, not the waterways. The watershed is defineed by the topographic limits. Like in a multipolygon, the ridges constitutes the outer ways, in the shape of a closed multipolygon. Actually I would prefer to call this sort of relation as "water_basin" or "drainage_basin" ( Also not as, since it's natural, not man made. I'd prefer something like natural=water_basin

Sergio (talk) 21:07, 11 April 2018 (UTC)

See also