Water for admin level 4

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Hi, 

I like the "water" version of file which make spatial join to not miss feature near the water.  But seems to me that it is available only for admin level 2.  Is there any way to have "water" version of other admin levels?   Assuming that it is not available, how can i come up with my own version...?   Is there algorithm/implementation released?   I can think of buffer with a certain distance from land/water boundary, but then i dont know how to draw polytical boundary over the water.

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Magnus
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The water version is "as is". In other words, that's how the polygons are in the OpenStreetMap database. Sometimes they include water, sometimes now. It's the land-only that has been manipulated by intersecting the coastline with the polygons.

The reason to why you mostly see it with admin level 2 is most likely because the country levels generally include national water, while deeper admin levels doesn't always do it. Seems to depend a lot on which country. I assume there isn't a real standard set there.

Regardless this is out of our scope. It has with the underlying (osm's) data to do and not with out representation. Though I can understand that it's very clear. Maybe even our name water is confusing since it just "may include water".

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Magnus
  • Answer
  • Answered

The water version is "as is". In other words, that's how the polygons are in the OpenStreetMap database. Sometimes they include water, sometimes now. It's the land-only that has been manipulated by intersecting the coastline with the polygons.

The reason to why you mostly see it with admin level 2 is most likely because the country levels generally include national water, while deeper admin levels doesn't always do it. Seems to depend a lot on which country. I assume there isn't a real standard set there.

Regardless this is out of our scope. It has with the underlying (osm's) data to do and not with out representation. Though I can understand that it's very clear. Maybe even our name water is confusing since it just "may include water".

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Yosuke Kimura

Thank you for the explanation for what the "water" is, where it came from.